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Introduction

In geometry, an angle is made when two rays are joined at the same location. The common point is referred to as the node or vertex, while the two rays are known as the arms of the angle. We use the symbol “\(\angle \)” to represent an angle. The word “angle” has its roots in the Latin word “Angulus”, before talking about congruent angles, let’s define the term. In geometry, two figures are said to be congruent if their size and shapes are the same. That suggests that they will completely overlap if we stack one figure on top of the other. These figures may be line segments, polygons, angles, or 3D objects.

Congruent Angle Construction

Corresponding angles are always congruent on congruent figures. Two situations are there while learning about the construction of congruent angles in geometry. They are
• Any measurement can be used to create two congruent angles.
• making a new angle that is comparable to the one already there
Let’s look at two angles that are congruent with each other.

In the figure above, the angles are equal in size (\({100^\circ }\) each). They might completely encircle one another. As a result, both of the above angles satisfy the concept of congruent angles.

The symbol \(\angle 1 \cong \angle 2\) represents the congruence of two angles.

Angle Congruence Theorems

Many theorems are built on the concept of congruent angles. The congruent angles theorem allows us to easily assess whether two angles are congruent or not. The following are the theorems:

• The vertical angle theorem
• The corresponding-angles theorem
• The alternate-angles theorem
• Congruent supplement theorem
• Congruent complements theorem

Let’s talk about how these theorems are stated. Different theorems can be used to demonstrate if two or more angles are congruent. The following are the theorems:

The vertical opposite angle theorem

If two lines intersect each other, then the vertically opposite angles are equal.

Congruent Complements Theorem

The next theorem, the congruent complements theorem, states that if two angles are complements of the same angle, then the two angles are congruent.

Congruent Supplements Theorem

According to the Congruent Supplements Theorem, two angles are congruent if they are supplements of the same angle.

The alternate interior angles theorem

This theorem states that the alternate interior angles are equivalent if a transversal intersects two parallel lines.

The alternate exterior angles theorem

This theorem states that the angles formed on the outer side of the parallel lines and opposite sides of the transversal, when a transversal joins two parallel lines, have to be equivalent.

The theorem of Corresponding Angles

If a transversal meets two parallel lines, the corresponding angles that result are congruent.

Summary

This article showed us that a pair of angles cannot be congruent unless their measurements are equal. The statements of congruence of vertical angles theorem, corresponding angles theorem, alternate angles theorem, congruent supplements theorem, and congruent complements theorem were the next ideas we learned. We next discussed a few examples of congruent angles. We also learned how the angles are congruent based on these theorems. When two unknown angles are regarded as congruent, as well as how to calculate an angle’s measure, were both covered. Finally, we solved several cases that illustrated the concept of congruence of angles.

1. What is an angle? What are the measuring units of angles, and what is the relation between them?

Ans. An angle is the elevation of one line from another. Angles are measured in two main unit systems, i.e., the degree system and the radian system. The degree system has 2 sub-divisions, minutes and seconds. 1 complete circle is 360 degrees, 1 degree has 60 minutes and 1 minute has 60 seconds, the degree system angles are always represented by whole numbers and any fractional part is moved on to the next subdivision. Whereas the radian system has no subdivisions and can be represented in whole numbers, fractions and decimals. In the radian system, 1 complete circle is \(2\pi {\text{ rad}}\).

\[{360^\circ } = 2\pi {\text{ rad}}\]

\[{1^\circ } = \frac{\pi }{{180}}{\text{ rad}}\]

\[1{\text{ rad}} = {\frac{{180}}{\pi }^\circ }\]

2.What do you mean by congruent angles?

Ans. An angle is said to be congruent to another angle if the two angles are equal in measure.

3.Are the following two angles congruent?

Ans. Two angles are congruent if they are equal in measure, in the following image, the 1st angle, by the vertically opposite angles property, is a right angle. For, the second angle, using the corresponding angles property we can say that the angle adjacent to it is also a right angle. Now using the linear pairs,

\[{90^\circ } + \angle 2 = {180^\circ }\]

\[\angle 2 = {90^\circ }\]

Hence, the 2nd angle is also a right angle. Thus, the two angles are congruent.

Want to dive deeper into the topic of congruence? Check out our article on “Congruence for Triangles“

Introduction

Animals come in a variety of shapes and sizes. Members of this kingdom are Multicellular, eukaryotic animals that have a heterotrophic mode of nutrition and their cells are devoid of cell walls. They are typically motile that move from one place to another. Animals come in a variety of shapes and sizes. 

Classification of Animal kingdoms based on their characteristics

Animal classification is based on various characteristics such as

• Arrangement of cells
• Symmetry
• Coelom or body cavity

Arrangement of cells

All animals are multicellular but the arrangement of cells within them is different. This arrangement of cells is known as the levels of the organization. Based on this animals are classified under

• The cellular level of organization- Animals at this level of organization generate loose clusters of cells. Eg. Sponges.
• Tissue level of organization-Animals under this level has cells that combine to form tissues and all tissues perform various bodily activities.
• Organ level of organization-  Animals with an organ-level organization are those in which tissues with the same functions group together to form an organ.
• Organ system level of organization-Organ system degree of organization is displayed when organs work together to produce an organ system that performs many physiological functions.

Symmetry

• The symmetry of an animal’s body can be used to classify it.
• The body exhibits three different types of symmetry.
• Asymmetry is symmetry where the plane is not divided into two equal halves. It was observed in the phylum Porifera (sponges).
• Radial symmetry is a symmetry that divides a plane passing through the central axis into two halves. This is seen in phylum Coelenterates, Ctenophores, and Echinoderms.
• When a  plane separates the body into two identical left and right halves then such symmetry is known as bilateral symmetry.
• Arthropods and annelids are two examples of animals with bilateral symmetry.

Coelom or body cavity

• The coelom is the space that is found between the body wall and the alimentary canal. Based on body activity organisms are classified as-
• Acoelomates- They do not have a body cavity. Eg- members of Phylum Platyhelminthes.
• Pseudocoelomates–They have a false body cavity. Eg. members of Phylum Aschelminthes.
• Coelomate- They have a true body cavity that is filled with coelomic fluid. This is seen in members from Phylum Annelida to Phylum Chordata.

Phylum belonging to Kingdom Animalia

Phylum Porifera

• They are also known as sponges.
• They are multicellular organisms that are organized at the cellular level.
• They have asymmetrical body shapes and are typically found in marine environments.
• They have a water canal system. Water enters the body through the Ostia (pores) that are lined up on the surface of the body. From here it is conveyed into the spongocoel. Water exists in the body through the osculum.
• The movement of water facilitates gas exchange, food capture, and water excretion.
• Porifera members are Hermaphrodites.
• Common examples are Spongilla and Sycon.

Phylum Cnidaria

• They are aquatic, sessile, free-living, and radially symmetric creatures.
• On their body, tentacles, have stinging capsules called cnidoblast. These cnidoblasts
• are defense mechanisms of the organism and it also helps in anchorage.
• They display tissue-level organization and diploblastic structure.
• They have a single opening mouth on the hypostome and both internal and external digesting systems.
• The basic body forms that Cnidarians displays are the polyp and the Medusa.
• Physalia and Adamsia are two examples.

Phylum Platyhelminthes

• They are called flatworms because of their dorsally flattened bodies.
• They live inside animals, including humans, and are endoparasitic.
• Some of them take nourishment straight from their host.
• They are triploblastic, bilaterally symmetric animals that are organized at the organ level.
• They have no true internal body to accommodate well-developed organs for proper functioning. 
• The development happens throughout several larval stages. Fertilization is internal.
• Taenia and Fasciola are two examples.

Phylum Annelida

• They can have a closed circulatory system and can either be terrestrial or aquatic, parasitic or free-living.
• They exhibit bilateral symmetry and organ-level organization.
• Segments and metameres are found on the body surfaces.
• Circular muscles in their bodies aid in mobility.
• The Annelida species perform sexual reproduction.
• Examples-Nereis and Hirudinaria.

Phylum Arthropoda

• In the Kingdom Animalia, it is the largest phylum that includes insects.
• They show bilateral symmetry and organ-level structure.
• They have joint legs and a tough exoskeleton
• Arthropods have a chitinous layer covering their belly, thorax, and other body parts.
• Through Malpighian tubules, they excrete.
• The development may be direct or indirect, and fertilization is typically internal.
• Eg- Cockroaches, Flies, Bees, etc.

Phylum Mollusca

• They are the second-largest phylum of the kingdom Animalia.
• They have an organ level of organization and may be terrestrial or aquatic.
• They have true bodies, triploblastic organization, and show bilateral symmetry.
• Most molluscs have calcareous shells covering their bodies.
• The head, visceral hump, and muscular foot make up the body.
• Internal fertilization occurs and they show indirect development.
• Examples include Pila and Chaetopleura.

Phylum Echinodermata

• Animals have calcareous skin coverings.
• They exist in aquatic settings that are organized at the organ level.
• While adults have radial symmetry, larval-stage animals have bilateral symmetry.
• They have a water vascular system that aids in breathing, locomotion, and food collection.
• There is no excretory system in them.
• Echinoderms show external fertilization and reproduce through sexual reproduction.
• Asteria and Echinus are examples.

Phylum Protochordata

• These creatures are triploblastic and bilaterally symmetric.
• They have a true body and, at some point in their life cycle, a notochord is present.
• They typically inhabit marine areas.
• Examples are Herdmania and Amphioxus.

Phylum Chordata

• This phylum includes creatures like birds and humans.
• The presence of a notochord is a trait shared by all species in this phylum.
• They have a single, hollow central nervous system that is located dorsally.
• A post-anal tail is present, which aids with movement.
• A pharynx is penetrated by gill slits.
• The phylum is further divided into subphyla Urochordata, Cephalaochordata, and Vertebrata.

Summary 

The largest kingdom that includes all animals is called Kingdom Animalia. Several criteria, including the level of organization, symmetry, coelom, segmentation, and notochords, are used to classify these species. Various phyla such as  Porifera, Cnidaria, Ctenophora, Platyhelminthes, Annelida, Arthropoda, Mollusca, Echinodermata, Protochordata, and Chordata make up this Kingdom.

Frequently asked question

1. Describe protozoans.
Ans: Protozoans are-

• Microscopic, unicellular, free-living protozoa are present in practically all ecosystems.
• They are typically parasitic and mobile. 
• Digestion of food by these organisms takes place through the process of Osmotrophy, which is the engulfment of food through cell membranes.

2. How are animals classified based on the circulatory system?
Ans: A network of arteries, veins, capillaries, and the Heart together is known as the circulatory system. There are two types of circulatory systems: open and closed systems.

• In an open system, the blood is pumped into a chamber outside the heart known as the hemocoel rather than being constrained to the blood vessels.
• In a closed system, the blood circulates in one direction from the heart to the surrounding vessels and then returns to the heart. In this system, the blood is contained within the blood capillaries.

3. What do diploblastic organization and triploblastic organization mean?
Ans:

• Diploblastic organization – It is the arrangement of cells in two layers, i.e outer ectoderm and inner endoderm. It is seen in Coelenterates 
• Triploblastic organization -It is a  three-layered arrangement of cells, i.e ectoderm, mesoderm, and endoderm. Common examples are Platyhelminthes, chordates, etc. 

Introduction

“Titration, also known as titrimetry, is a common quantitative chemical analysis method used in laboratories to determine the unknown concentration of an identified analyte. Because volume measurements are important in titration, it is also referred to as volumetric analysis. As a standard solution, a reagent known as the titrant or titrator is prepared. To determine the concentration, a known concentration and volume of the titrant reacts with a solution of the analyte or titrand. The volume of titrant reacted is referred to as the titration volume. Titrations come in a variety of forms, each with its own set of procedures and objectives. Acid-base titrations and redox titrations are the two most common types of qualitative titration.”

What do you understand by the term Acid Base Titration?

“An acid-base titration is a technique used to experiment with and learn about a solution containing an acid or a base. A base (alkali) is titrated with an acid, and an acid is titrated with a base (alkali). In Titration, the endpoint is determined by the use of an indicator. Acid-base titrations are in use to calculate the amount of a known acidic or basic substance through acid-base reactions. Titration refers to determining the concentration or rank of a solution in relation to water with a pH of 7. A standard solution is added using a device known as a burette. Titration is the process of adding a standard solution until the reaction is complete. It is understood that the substance to be determined is titrated.”

Types of Acid Base Titration

• Strong Acid and Strong Base-When a strong acid and a strong base react, exothermic reactions always occur. For example, a reaction with Hydrochloric Acid (HCl) and Sodium Hydroxide (NaOH).

\[{\bf{NaOH}}{\rm{ }} + {\rm{ }}{\bf{HCl}}{\rm{ }} \to {\rm{ }}{\bf{NaCl}} + {{\bf{H}}_2}{\bf{O}}\]

• Strong Acid and Weak Base-Example of such types are when Hydrochloric Acid (Strong Base)  reacts with Ammonia (Weak Base)

\[{\bf{N}}{{\bf{H}}_3} + {\rm{ }}{\bf{HCl}}{\rm{ }} \to {\rm{ }}{\bf{N}}{{\bf{H}}_4}{\bf{Cl}}\]

• Weak Acid and Strong Base-Example of such types are when Ethanoic acid (Weak Acid) and Sodium Hydroxide (Strong Base) react

\[{\bf{C}}{{\bf{H}}_3}{\bf{COOH}}{\rm{ }} + {\rm{ }}{\bf{NaOH}}{\rm{ }} \to {\rm{ }}{\bf{C}}{{\bf{H}}_3}{\bf{COONa}}{\rm{ }} + {\rm{ }}{{\bf{H}}_2}{\bf{O}}\]

• Weak Acid and Weak Base-Example of such types are when the reaction between Ethanoic Acid (Weak Acid) and Ammonia (Weak Base) occurs.

\[{\bf{C}}{{\bf{H}}_3}{\bf{COOH}}{\rm{ }} + {\rm{ }}{\bf{N}}{{\bf{H}}_3} \to {\rm{ }}{\bf{C}}{{\bf{H}}_3}{\bf{COON}}{{\bf{H}}_4} + {\rm{ }}{{\bf{H}}_2}{\bf{O}}\]

What is a Titration Curve

A titration curve is a plot of the analyte solution’s pH versus the amount of titrant added as the titration progresses.

• Strong Acid and Strong Base– As the titration begins with a strong acid, the pH of the solution is extremely low (around 1) when no base is added. The pH gradually rises as the base is gradually added. The equivalence point is the point at which all acids and bases have been neutralized. On the plot, this is indicated by a sharp increase or jump in pH. As we continue to add a base, the pH of the solution rises dramatically.
• Strong Acid and Weak Base- The solution’s initial pH indicates a weakly acidic solution. The titrant is a strong base, as indicated by the high final pH. The equivalence point is at a pH greater than 7.

• Weak Acid and Strong Base-At the start of the titration, the pH of the solution is approximately that of the weak acid in water. All the weak acid is neutralized and converted to their conjugate base at the equivalence point. The pH at the equivalence point, however, does not equal 7. This is because a conjugate base is produced during the titration. The resulting solution is somewhat simplistic.
• Weak Acid and Weak Base-The pH change around the equivalence point decreases significantly as the acid or base being titrated weakens (its \({\rm{p}}{{\rm{K}}_{\rm{a}}}{\rm{or p}}{{\rm{K}}_{\rm{b}}}\) increases). The curve becomes so shallow with very dilute solutions that it can no longer be used to determine the equivalence point.

What are the uses of Acid-Base Titration?

1. Acid-base titrations are generally preferred for determining an analyte’s unknown acid or base concentration.
2. Acid-base titrations are a type of chemical analysis that is measurable.
3. Titrations of acids and bases have the potential to be used in pharmaceutical applications.
4. Titrations of acids and bases can be used in environmental analysis.

Summary

A titration is a method of carrying out a chemical reaction between two solutions by controlling the addition of one solution (the titrant) from a buret to the other, allowing measurements to be taken throughout the reaction. A titration is useful for measuring the pH of an acid-base reaction at various points throughout the reaction.

Frequently Asked Questions 

1. What is Titrant?

Ans. The titrant is a chemical solution of a known concentration that is added in titration.

2. What is an Equivalence point?

Ans. The equivalence factor in titration is the factor at which simply sufficient titrant is brought to absolutely neutralize the analyte answer. The answer best incorporates salt and water on the equivalence factor in an acid-base titration, 

Moles of acids=moles of bases

3. What is Buffer solution?

Ans. The buffer answer is described as an answer that doesn’t alternate in Hydrogen ion attention whilst a small quantity of acid or base is brought to it.

Introduction

The definition of a rational number is a fraction of two numbers in the form \(\frac{p}{q}\), where p and q can both be integers but q cannot be equal to 0. Rational numbers include whole numbers, integers, and numbers with terminating decimals. Although rational numbers need not necessarily be fractions, any fractions can be rational numbers. The area of mathematics that deals with symbols and variables are called algebra. Natural numbers, Integers, 0, and other types of numbers are all included in rational numbers. Positive and negative numbers are both part of integers. Therefore, we can divide rational numbers into positive rational numbers and negative rational numbers. Positive rational numbers include, for instance, \(1,\frac{3}{16},\frac{25}{2}\), etc. These are examples of negative rational numbers: \( – 3, – \frac{1}{2}, – \frac{5}{3}\), etc.

Rational Numbers

The definition of a rational number is a fraction of two numbers in the form \(\frac{p}{q}\), where p and q can both be integers but q cannot be equal to 0. Rational numbers include whole numbers, integers, and numbers with terminating decimals. Although rational numbers need not necessarily be fractions they can be converted into one, all fractions are rational numbers.

Positive and Negative Rational Numbers

Those rational numbers that have both positive or negative numerators and denominators are known as positive rational numbers. Positive numbers that follow logic are always bigger than zero. For instance, when we divide \(\frac{8}{9}\), we obtain 0.88, which is more than 0, indicating that \(\frac{8}{9}\) is a positive rational number.

Those rational numbers that are negative because their numerators and denominators have opposite signs are known as negative rational numbers. Positive irrational numbers are never greater than zero. For instance, \( – \frac{{12}}{{13}}\) yields -0.92, which is both lower than 0 and a negative rational integer.

Positive Numbers

The number line can also be used to represent positive numbers. According to the illustration below, the numbers that are on the right side of the number line are thought of as positive numbers. Positive numbers are those whose value is consistently higher than zero.

Note: When a number is left unsigned, it is considered to be positive. For instance, the positive integers 45 and +45 are identical and both 45.

Negative Numbers

Similar to the positive numbers, the number line can also be used to represent negative numbers. According to the illustration below, the numbers that are on the left side of the number line are thought of as negative numbers. Negative numbers are those whose value is consistently higher than zero.

Positive, 0 and negative rational numbers are the three subcategories of rational numbers.

A rational number is positive if both the numerator and the denominator have the same sign, such as both being positive or both being negative, and it is negative if the numerator is negative and the denominator is positive or vice versa.

Take an example of \(\frac{3}{5}\) and \(\frac{{ – 3}}{{ – 4}}\) they are both positive since the sign of both numerator and denominator are the same in the respective numbers, whereas \(\frac{{ – 3}}{4}\) and \(\frac{4}{{ – 5}}\) are both negative since the signs in numerator and denominator are opposite.

Algebra of Rational numbers

Rational Numbers like all the other number categories under the real number have four basic binary operations, i.e, addition, multiplication and the inverse operations subtraction and division.

Addition and Multiplication of Rational numbers have the following properties,

Closure Property

Addition and Multiplication of rational numbers is closed, i.e., when two rational numbers are operated with these operations the result is always rational number.

Associative Property

Addition and Multiplication of rational numbers is associative, i.e., the order of operations does not change the result when the same operation is repeated between 3 or more numbers. Mathematically, for three rational numbers a, b and c

\[a + (b + c) = (a + b) + c{\text{ and }}a \cdot (b \cdot c) = (a \cdot b) \cdot c\]

Existence of Identity Property

The Identity element is known as the element which when operated with any other element, has no effect on it. For Addition of rational numbers, 0 is the identity element, and for multiplication it is 1.

Mathematically,

\[a + 0 = 0 + a = a{\text{ and }}a \cdot 1 = 1 \cdot a = a\]

Existence of Inverse Property

The Inverse of an element is known as the element which when operated with the first element, results in the identity. Rational numbers have additive inverse for all the numbers, and they are their negative counterparts, such as for 3 it is -3, for \(-\frac{5}{6}\) it is \(\frac{5}{6}\). For multiplication however, not all rational numbers have inverse, 0 is the rational number which does not have a multiplicative inverse, because by definition multiplicative inverse of a rational number \(a\) would be \(\frac{1}{a}\), but by the definition of rational numbers, 10 is not a rational number.

Commutative Property

Addition and Multiplication of rational numbers is associative, i.e., the order of element does not change the result. Mathematically, for two rational numbers a and b,

\[a + b = b + a{\text{ and }}a \cdot b = b \cdot a\]

Summary

In this article we learned about Rational numbers, positive and negative rational numbers. A rational number is defined as the number which can be represented by the form, \(\frac{p}{q}\) where p and q are coprime integers and \(q\ne 0\). The rational numbers, just like integers, can be divided into 3 categories i.e., positive, negative and 0. Positive rational numbers are those that are greater than 0, and negative are the ones that are smaller. The positive and negative rational numbers are represented on right and left sides of the number line respectively.

FAQs

What are Rational numbers? How do you identify rational numbers in decimal form?

Ans. Rational numbers are defined as the numbers which can be represented by the form, \(\frac{p}{q}\) where p and q are coprime integers and \(q \ne 0\). In decimal form, the numbers that have either terminating decimal expansion or if non-terminating then, repeating decimal expansion are rational numbers.

What is Rule for identifying positive and negative rational numbers from their fractional form?

Ans. There is one simple rule to identifying positive and negative rational numbers from fractional form

• If the numerator and denominator have the same sign, both either positive or negative, then the number as a whole is positive.
• If the numerator and denominator have different signs, numerator positive and denominator negative or vice versa, then the number as a whole is negative.

What are the numbers that are not rational called? What is the general identification of those numbers in the decimal form?

Ans. The real numbers that are not rationals, i.e., they cannot be represented in the form, \(\frac{p}{q}\) where p and q are coprime integers and \(q \ne 0\), are known as Irrational numbers. These are the numbers whose decimal expansion has infinite digits after the decimal, and they never repeat the same pattern.

Introduction

The definition of agriculture is frequently misunderstood to mean just the production of crops for food and fiber. Agriculture, however, extends beyond just growing plants, it includes the breeding of livestock for their beneficial products. Since the beginning of time, humans have been raising animals for their own needs. Since humans first domesticated animals some 13,000 years ago, they have developed innovative techniques to increase both the quality and quantity of the things they can produce from animals. 

Types of Animal Husbandry

Dairy Farming

• The practice of raising dairy animals, such as cows, buffalo, goats, and others, for milk production and its subsequent processing to produce products like butter, ghee, cheese, and cream, among other things, is known as dairy farming.
• Native Indian cow and buffalo breeds including the Gir, Sahiwal, Red Sindhi, Siri, Mahiwal, Surti, and Jaffarabadi, as well as exotic breeds like Jersey, Red Dane, and Holstein Friesian, are frequently bred for their desirable traits.
• When raising cows to extract milk, it is essential to maintain the required standards of health and hygiene.
• Good quality and safe-to-consume products are ensured by the good health and excellent living conditions of the animals.

Learn More about Agriculture. Check out more videos in Science Class 8 Lesson 1. Clear your doubts from the Science experts teacher.

Poultry Farming

• The practice of domesticating and raising birds, such as hens, cocks, ducks, geese, and turkeys, for their meat, eggs, and other products is known as poultry farming.
• Different techniques are used by poultry farmers to raise chickens.
• The most popular method is intensive poultry farming, in which hundreds of birds are frequently raised in tier-by-tier battery cages.
• Farmers are becoming more conscious of the drawbacks of intensive farming, which has led to a rise in the popularity of free-range farming.
• In this style of poultry farming, the birds are given free access to a large area during specific hours of the day.
• Better health and disease resistance are encouraged by this practice.
• In poultry farming, hens are raised primarily for two products: eggs or meat.
• It is advised to provide a healthy, disease-free environment, along with decent, nourishing meals and spacious places.

Pisciculture

• Fish rearing for food is often known as pisciculture or fish farming.
• Typically, fish tanks or other enclosures such as ponds are used to raise the fish.
• The fish are fed artificially and later harvested.
• In composite fish culture, both domestic and foreign varieties are raised in the same pond or enclosure.
• The fish that are selected to be raised together must be able to co-exist.
• The most popular fish species raised for food include trout, carp, salmon, tuna, tilapia, etc.

Apiculture

• Apiculture is the practice of raising bees in colonies in places called apiaries to produce honey and other items like royal jelly, beeswax, etc.
• In addition, bees are also utilized for their pollination services.
• For the colonies to expand, beekeepers frequently employ wooden hives.
• Bee farming is a low-cost, low-labor method of farming.
• Bees can be easily grown without the requirement for any fertile ground.
• However, it is important to make sure the bee farm is situated close to a flower garden with enough pollen and nectar.
• In addition, it is necessary to prevent the use of insecticides near the apiaries.

Advantages of Animal Husbandry

Following are the advantages of animal husbandry in agriculture and human welfare.

• The dairy industry in animal husbandry makes a significant contribution to the global food sector by offering a wide range of goods, including milk and its derivatives like butter, various types of cheese, ghee, cream, etc.
• Dairy farming makes a vital contribution to a nation’s economy. With 186 million tonnes of milk consumed yearly. India is one of the world’s largest milk producers.
• In addition to being raised for their milk, dairy farm animals are also used for their flesh.
• Because of its high protein content and flavor meat is a very popular food item.
• Livestock and poultry raised on the grounds, generally graze there, this helps in suppress weed development.
• The items that are obtained from all the reared animals help in increasing the nation’s economy as they are exported to various foreign countries.
• All these animal-rearing activities have generated employment options in rural areas. 
• It has increased food security and provided money to rural impoverished people.
• Utilizing animal waste as manure on farmland is one example of how sustainable practices to aid in the efficient management of waste. It encourages effective nutrient cycling.
• Moreover, manure can be used in fish meals.
• Manure and cow dung are valuable sources of fuel.
• Additionally, animal husbandry is managed to produce fibers that are crucial to the textile industry.

Summary

• The process of raising livestock to exploit their products is known as animal husbandry.
• Dairy farming, poultry farming, fish farming, and bee farming are the four main subfields of animal husbandry.
• Animal husbandry procedures must assure a safe, secure, and healthy environment for the animals’ well-being, which will in turn yield high-quality goods.
• Animal husbandry produces a number of significant goods that are essential to our daily life.
• Additionally, animal husbandry creates job opportunities.

Frequently Asked Questions

1. Differentiate between layers and broiler.
Ans: 

Layers	Broilers
These are chickens that are raised for egg production.	These are chickens that are raised for meat production.
They need protein in less quantity in their  diet.	They require a protein-rich diet.
They need proper spacing and lighting.	They do not need much spacing and lighting.

2. Enlist types of Honey bees used in apiculture.
Ans: Honey bees reared for apiculture are-

• Apis dorsata or The Rock Bee
• Apis cerana indica or The Indian hive Bee
• Apis mellifera or The European Bee
• Apis florea or The Little Bee.

3. Which state of India produces the maximum number of fish under pisciculture?
Ans: Andhra Pradesh is the highest fish-producing state in India. It produces around 34.50 lakh tonnes of fish per year.

Introduction

A population is a collection of people belonging to the same species who coexist in one location. These people are susceptible to the same environmental factors and need the same resources to survive and develop. When analyzing the population, we categorize the population based on its size and location.

A population is never constant and always exhibits some fluctuations. Natality, mortality, immigration, and emigration are some terms used to characterize these dynamic oscillations that occur in a population. Mathematical methods, such as the logistic growth models and the exponential growth curve, are used to study population dynamics.

Population Growth

The term “population growth” describes the shift in the total number of people within a population. This growth can be positive if the no.of individuals increases in an area and population growth can be termed negative if the no.of individuals decreases in an area.

Birth, immigration, death, and migration are the four main factors that influence change in the number of individuals in an area. The first two elements increase the population, whilst the latter two cause it to decrease.

Growth models that describe the basic growth trend in a population

There are two growth models which describe the basic growth trend in a population. The two models are-

Exponential Growth Model

• When an ideal environment with unlimited resources is taken into account, this growth model represents the rapid growth rate of a population.
• Under ideal circumstances, a small number of individuals would have the means to develop and propagate. This is because they are not constrained by any external forces.
• Every birth would result in an increase in population and every death will decrease the population.
• This model, is often employed to find out the maximum capacity of growth and the kind of ideal conditions required for such growth to take place.

Mathematically, it can be shown as follows-

\(\frac{{\Delta {\rm{ }}N{\rm{ }}}}{t} = {\rm{ r}} \times {\rm{N }}\; –  –  –  –  – 2\)

\(\frac{{\Delta {\rm{ }}N{\rm{ }}}}{t} = {\rm{ }}B{\rm{ }} – {\rm{ }}D{\rm{ }}\; –  –  –  –  – 1\)

Where \(\frac{{\Delta {\rm{ }}N{\rm{ }}}}{t}\)= change in population size(Δ N) over a time interval (t)

B – D = per capita number of births – per capita number of deaths

B – D can be substituted by the quantity r, hence the equation becomes:

\(\frac{{\Delta {\rm{ }}N{\rm{ }}}}{t} = {\rm{ r}} \times {\rm{N }}\; –  –  –  –  – 2\)

Applying differential calculus to the above equation, we get:

\(\frac{{{\bf{dN}}}}{{{\bf{dt}}}}{\rm{ }} = {\rm{ }}{\bf{rN}}\;\)

where r = per capita change in population size occurring at each instant of time / intrinsic rate of population growth 

From this equation, the following cases arise:

1. If r = 0, there’s no change in population size
2. If r > 0, population size increases exponentially 
3. If r < 0, population size declines exponentially

Logistic Growth Model 

• The Logistical Model is based on the notion that as an individual is “added” to a population, they have access to fewer resources, due division of resources amongst individuals. This is in contrast to the exponential model, which assumes limitless resources.
• Realistically, a certain geographic area can only support a certain number of inhabitants while ensuring that each has equal access to all available resources.
• This maximum limit of population growth that an environment can sustain is known as its carrying capacity, represented as (K).  
• Limiting variables such as water, food, shelter, protection from predators, etc. govern the carrying capacity of an environment.
• The reproductive capacity of individuals is reduced when resources are scarce and the area is congested.
• Similar to this, factors like an increase in disease incidence can cause the per capita death rate to rise.
• Declining per capita population growth rate is the result of higher per capita mortality rates and lower per capita birth rates.
• Therefore, r decreases as N increases. In the logistic growth the model, per capita growth rate tends to 0 as population size approaches K. 
• If (K-N) = no. of excess individuals that the environment can support, then 
• (K-N)/K = the amount of K still available for population growth
  

           \[\;{\rm{\;}}\frac{{{\rm{dN}}}}{{{\rm{dt }}}}{\rm{ =  }}\frac{{{\rm{rN }}\left( {{\rm{K – N}}} \right)}}{{\rm{K}}}\;\]

Where dN/dt = rate of change in population size at time t

            N = population density 

           r= intrinsic rate of growth under ideal conditions

           K = carrying capacity  

Factors that Influence Population Fluctuation:

The population is susceptible to regular dynamic variations brought on by the influx of new inhabitants into a region or the emigration of residents from that region. The following are the factors that influence population change.

• Natality- It is also known as birth rate and is defined as the number of children born in a certain area per unit of time. Natality rises when an organism reaches its maturity and declines as it nears senescence. There are two types of natality-

• • Maximum/ absolute natality– This refers to the maximum number of persons that might theoretically be born under optimal and non-resource-limiting circumstances. It is also called the fecundity rate.
  • Ecological/realized natality- This is the actual population growth brought on by births under given environmental circumstances. It is  also known as the “fertility rate.”

• Mortality-It is also known as the death rate and is defined as the number of individuals that have died in a population per unit of time. There are two types of mortality-
  • Specific or potential mortality- This refers to a theoretical decrease in the no. of indualivials under ideal climatic and resource availability conditions. People pass away through natural reasons, such as old age.
  • Ecological/realized mortality-Ecological/realized mortality is the actual death of members of a population as a result of ongoing environmental issues and resource shortages. With changes in population and environment, this type of mortality keeps on changing.

• Immigration-
  • The term “immigration” describes the flood of new people from other places into a new geographic area.
  • It enhances population growth by increasing the number of individuals who already live in the area.

• Emigration
  • Emigration is the movement of people away from a certain geographic area.
  • It drives people out of the area, which decreases the local population there.

Summary

• Population growth refers to an increase in the number of people living in a particular location.
• Four significant factors—natality, death, immigration, and emigration—affect population growth.
• Models of population growth aid in analyzing and forecasting trends in population growth.
• The exponential model is theoretical since it is based on unlimited resource availability.
• The logistical model is realistic and takes into account the environment’s carrying capacity and limited resources.
• Natality is the number of children born in a region per unit of time.
• The number of individuals who die in a population per unit of time is known as mortality.
• Immigration is the movement of new people into a country or region from other places.
• Emigration is the movement of people out from a specific location.

Frequently Asked Questions

1. What benefits does population growth have?
Ans: Benefits of population growth are-

• Economic growth can be caused by population expansion. 
• more parents are investing in their children as a result of more births.
• The economy is supported by rising spending on food, clothing, textbooks, recreational equipment, and toys.

2. What effects does population expansion have on the environment?
Ans: Population growth has the following impacts on the environment-

• The consumption of resources including land, food, water, air, fossil fuels, and minerals increases to a great extent.
• Lots of waste products are generated due to the consumption of various resources.
• Waste products such as hazardous substances, greenhouse gases, and air and water pollutants are also generated, harming the environment.

3. Mention different types of populations.
Ans: The different types of the population are-

• Finite population
• Infinite population
• Existent population
• Hypothetical population

Introduction

Any living organism’s fundamental structural and functional unit is its cell. In any living organism, cells serve a variety of important tasks in terms of growth, development, and daily activities. They perform these activities through chemical processes that take place inside specialized structures called cell organelles. Eukaryotic cells without a cell wall are referred to as animal cells. Since these cells are eukaryotic, they exhibit the existence of membrane-bound organelles as well as a well-defined nucleus that is protected by a nuclear membrane. It has been noted that animal cells are smaller than plant cells. According to their role in the animal body, they also exhibit a wide variety of sizes and shapes.

Learn More about Animal Cells. Check out more videos in Science Class 8, Lesson 8 – Cell-the unit of life.

Animal Cell Organelles

Cell Membrane

• It is a unique structure that encircles the animal cell and gives it structural stability.
• It controls the movement of various molecules in and out of the cell.
• The characteristic property of the cell membrane is selective permeability.
• A phospholipid bilayer, as well as many kinds of specialized proteins, lipids, and carbohydrates, make up its structure.
• The cell membrane is termed “amphipathic” because the phospholipids of the cell membrane have a hydrophilic head and a hydrophobic tail.
• The cell membrane also plays a critical role in shielding the cell from the outside environment.
• Specialized proteins termed transport proteins aid in the transit of polar molecules through the cell membrane.

Nuclear Membrane

• It can be described as the nucleus’ outer boundary.
• It is the membrane that confines the nuclear area from the cytoplasm It is a double-membrane structure.
• It protects the genetic material from chemical reactions that take place in the cytoplasm.
• The movement of materials into and out of the nuclear area is controlled by the nuclear membrane.
• It consists of nuclear pores, which are points of entry into the nucleus. 
• These nuclear pores assist in the transportation of material and help in regulating their movement.

Nucleus

• It is frequently referred to as the cell’s “control center.”
• It is the area where the cell’s genetic material is kept and is in charge of controlling daily cell functions and multiplication.
• It is made up of the nuclear membrane, the genetic material, chromatin, nucleolus, and nucleoplasm.
• The production of ribosomes takes place in the nucleolus.
• DNA, which makes up chromosomes, contains instructions for cell division and growth.

Centrosome

• Animal cells only have these organelles, which are missing from plant cells.
• During cell division, they serve as the main organizing unit for microtubules.
• They are made up of two centrioles, which are two groups of microtubules that are kept perpendicular to one another.
• The development of spindle fibers, which bind to chromosomes in the metaphase and move them toward the poles in the anaphase, is aided by these cells.

Lysosome (Cell Vesicles)

• It is frequently referred to as the cell’s suicide bag.
• These membrane-bound organelles are crucial for breaking down big molecules and eliminating waste from the cell.
• It has an acidic pH and a wide variety of hydrolytic enzymes that aid in its function in the disintegration of molecules.
• Lysosomes develop as budding from the Golgi body, whereas the endoplasmic reticulum makes the hydrolytic enzymes.

Cytoplasm

• It refers to the thick liquid that envelops cellular volume.
• The cytoplasm, includes the cytosol, various organelles (apart from the nucleus), and other macro- or macromolecules.
• The majority of cellular responses and metabolic processes take place there.
• It serves as a matrix in which the other organelles are suspended.
• The fluid nature helps molecules flow more easily inside cells.

Golgi apparatus

• In the Golgi apparatus, molecules created in the endoplasmic reticulum are packaged, modified, and transported to their final location.
• The molecule that has to be delivered is contained in vesicles made by the Golgi system.
• It has two primary faces: the forming face, also known as the cis face, where vesicles attach to be modified in the Golgi cisternae, and the mature face, also known as the trans face, where the vesicles are released.
• Lysosome synthesis is also carried out by the Golgi apparatus.

Mitochondrion

• These are frequently referred to as the “powerhouse” of the cell since they participate in ATP creation.
• This organelle is referred to as a semi-autonomous organelle because it has its own DNA.
• Within this organelle, cellular respiration occurs to finally produce energy.
• It also plays a role in apoptosis, cell communication, and signaling. Other activities include the storage of calcium ions to maintain a balance of calcium ions in the cell.

Ribosomes

• They are small organelles that are not membrane-bound.
• They are mostly located in the mitochondrial matrix, the nucleus, and the cytoplasm.
• They serve as the main location for the synthesis of protein.
• It typically has 2 subunits. It can be distinguished as the 70s and 80s ribosomes in prokaryotes and eukaryotes, respectively.

Endoplasmic Reticulum (ER)

• ER is regarded as the cell’s biggest single membrane-bounded compartment.
• It is made up of a network of vesicles, tubules, and cisterns.
• Here Protein synthesis and protein modification take place.
• The membrane of ER is responsible for the synthesis of lipids and proteins for all organelles of the cell
• Depending on how they appear under the microscope, they are divided into the rough and smooth endoplasmic reticulum.

Vacuole

• It is a unique organelle that is used to store extra cell materials.
• It is surrounded by a tonoplast membrane.
• Water can occasionally be found in vacuoles, which gives the cell a turgor pressure that helps it keep its form and survive adverse circumstances.

Functions of an Animal Cell

The fundamental tasks of an animal cell are-

• Reproduction to insure the continuation of the generation 
• Physical growth of the organism.
• Respiration and metabolism fulfill the energy demands of the body.

Animal Cell types

Skin Cells

• These cells are located on the outside of the body and are frequently very thinly layered.
• These cells act as the body’s initial line of defense against germs and various stresses coming from the outside.
• Melanocytes are an example.

Muscle Cells

• These cells have specialized functions that help in the movement of organisms.
• The skeletal, cardiac, and smooth muscles are some examples.

Nerve Cells

• These long, branched cells, also known as neurons, carry electrical impulses throughout the body, aiding in the coordination and control of the entire body.
• Along with neurons, glial and Schwann cells are also present.

Blood Cells

• Red Blood Cells (RBC) and White Blood Cells are the two primary types of Blood cells.
• RBCs utilizing the pigment hemoglobin, function as a transporter of oxygen throughout the body.
• WBCs also referred to as leukocytes, are the body’s defenders that resist and fight infections.

Fat Cells

These large cells, also known as adipocytes, are responsible for storing fat droplets or lipids when the body has an excess of them.

Summary

• Animal cells are made up of various organelles such as Ribosomes, centrosomes, Endoplasmic Reticulum, Nucleus, Nuclear membrane et,c.
• Animal cell types include- skin cells, Muscle cells, Nerve cells, Blood cells, etc.
• Thus, all the cells and their organelles work in unison to bring about proper control and coordination of the entire body.

Frequently Asked Questions

1. Who developed the plasma membrane model?
Ans: Singer and Nicolson presented the fluid mosaic model of the plasma membrane in 1972. According to this, the cell membrane bilayer is made up of phospholipid molecules and proteins are present on the surface and are embedded in the lipid bilayer.

2. What three types of lysosomes?
Ans: The lysosome’s type:

• Primary lysosomes: These are lysosomes that have just formed.
• Secondary lysosomes: When primary lysosomes and phagosomes combine, secondary lysosomes are produced.
• Autophagosomes: They are formed by the digestion of intracellular organelles by the process of autophagy.

3. What are the functions of smooth ER?
Ans: Smooth ER is a membrane-bound organelle that is devoid of ribosomes. The main function of this organelle is the synthesis of carbohydrates, lipids, and steroids. It also performs the metabolism of foreign compounds such as drugs and toxins.

Introduction

The history of India and the Subcontinent under the Mughal Empire underwent significant upheaval in the 16th and 17th centuries. The strong Rajput kings of Northern India were gradually losing control over diverse regions. The Mughals, on the other hand, could not enlarge their empire across the entire nation. The most effective tactic for enlarging their empire was Akbar’s plan to form marriage ties with the Rajput’s. The Rajput’s were likewise prepared to strengthen the Mughal Empire for their own political gain. They freely gave their daughters in marriage to the Mughal emperors in exchange for money and respected positions in the Mughal empire.

Mughal alliances with the Rajput’s

• The Rajput’s were an important part of Akbar’s diplomatic plan to strengthen their grip over the nation. He had faith that Rajput’s would supply them with a dependable and powerful military.
• Rajput’s performed a variety of tasks under Emperor Akbar during the Mughal era.
• Rajput’s were given money and several significant posts in the government, including the office of Mansabdars, in recognition of their contributions to the defense and expansion of the Mughal empire.
• Emperor Akbar eliminated the Jizya Tax and the Pilgrimage Tax for the Hindus as the alliance grew over time.
• Through reconciliation strategies with Hindus, particularly with the Rajput’s Emperor Akbar gradually extended the Mughal Empire into Northern India and, to some extent in the Deccan region.

Akbar’s Marriage to Rajput Girls

• As a part of the New Diplomatic Strategy, a marriage alliance was created between the two ruling families, the Mughals and the Rajput’s. The Rajput’s decided to barter their daughters for political gain and monetary benefits.
• The first Rajput woman to marry the Mughal Emperor Akbar and gain access to the Mughal zenana was known as Jodha Bai in 1562. She was Raja Bihari Mal’s (Bharmal)daughter, the ruler of Amber.
• The Rajput’s gained a lot of benefits and influence by arranging for her marriage to the Mughal monarch.
• Raja Bhagwan Das, the brother of Akbar’s wife, rose to the rank of commander in the Mughal cavalry.
• Similar to this, Rao Kalyanmal of Bikaner wished to marry Emperor Akbar to his two nieces, Raj Kanwar and Bhanumati.
• Around the same period, Rajkumari Nathi Bai, the daughter of the ruler of Jaisalmer Hari Raj, was also going to marry Emperor Akbar. Akbar also gave his son Kunwar Sultan Singh a position of honor in the palace.

King Akbar was a great ruler and hence never objected to them following their own Hindu faith. He even provided his wives’ parents and other royal relatives with respectable jobs. All the wives were free to follow their Hindu rites and prayers just as they had in their paternal home. Also, Akbar never attempted to convert them to Islam.

Jahangir’s Marriage to Rajput Girls

Jahangir, Akbar’s successor, and son, also kept up his marriage ties to the Rajput. Prior to taking the throne, Jahangir wed Mani Bai, a Kachchwaha princess who was the daughter of Raja Bhagwant Das. Then, after ascending to the position of Emperor, he wed numerous Rajput women. Notably, the daughters of Jagat Singh Kachchawaha and Ram Chandra Bundela also married King Jahangir. The last union between the Rajput and the Mughals took place in 1715 when Indira Kanwar, the daughter of Marwar King Ajit Singh, married Emperor Farrukhsiyar.

List of marriage alliances between the Mughals and the Rajput

Here is a list of marriage alliances between the Mughals and the Rajput-

Summary

In Indian history, the Mughals were the most influential and powerful kings. The Mughals nearly completely expanded their Empire during the 16th and 17th centuries. The Turko Afghan Sultanate was taking control of the regions that the Rajput kings once ruled in North and North East India. The Turko Afghan sultanate was overthrown by the Mughals. The Mughals thus proved to be very powerful, But when Akbar assumed control, he understood the importance of having a reliable and powerful military. He then developed a fresh approach to diplomacy wherein he started making alliances with the Rajput by marrying their daughter. The first Rajput princess who married King Akbar was Jodhabai. These alliances helped in the growth of the Mughal empire and also gave various benefits to the Rajput who married their daughters to the Mughal King..

Frequently Askes Questions

1. Who were the Rajput?
Ans:  The Rajput were a military clan renowned for their valour and fidelity. The Sanskrit term “Raja Putra,” which implies a King’s son, served as the inspiration for the name “Rajput. From the sixth until the twelfth centuries, they controlled India.

2. Give a short explanation of the Mughals.
Ans:   The Timurid dynasty included the Mughals. The Turco Mongols of Central Asia were the ancestors of this dynasty. They took control of India in 1526, and by 1707 they had taken control of the whole subcontinent, which included modern-day India, Afghanistan, Sri Lanka, Bangladesh, and Pakistan. They held power over India till the 1850s.

3. Who was Emperor Akbar?
Ans:  Emperor Akbar’s full name Abu’l-Fath Jalal-ud-din Muhammad Akbar was the son of emperor Humayun. He served as the third Mughal emperor from 1556 to 1605. He was known as “the great” emperor due to a number of his achievements such as-

• The expansion of the Mughal Empire across the Indian subcontinent.
• Tolerance towards various other religious beliefs.
• His administrative reform initiatives for the betterment of society.
• His progressive attitude to end tax discrimination against Muslims and Hindus.

Introduction

In the 1600s, the East India Company, a trading organization, of Britain came to India. At first, EIC’s primary goal was to purchase raw materials from India at the lowest possible cost, sell them to other countries, and reap the maximum financial benefits. in 1707. After the death of Aurangzeb, the last powerful emperor of the Mughal empire, the EIC stopped paying taxes to Indian monarchs. They viewed it as a chance to increase their earnings. Bengal was where the British established their first factory, and after victories at Plassey and Buxar, they gained complete dominance over the region. As a result of these two conflicts, EIC’s stance changed; they now desired to rule and control India because doing so would increase their profits. British officials appointed residents in Indian states had begun meddling in internal affairs as well. They implemented the subsidiary alliance doctrine, which forbade the partner state from maintaining its own armed forces and instead stationed the British army there. The king of that state paid the full cost of this arrangement. Because of this strategy, the British gained supremacy in India. The Doctrine of Lapse was the final annexation strategy the EIC used before achieving complete control over India. This policy was first presented by Lord Dalhousie, Governor General, in 1848.

The Doctrine of Lapse

• In 1848, Lord Dalhousie, the Governor General, instituted this strategy.
• According to the Doctrine, if a king died without a masculine heir, that country would inevitably fall under British control.
• Dalhousie opposed the king’s prerogative to adopt an heir because he wanted to fully destroy the Mughal empire. He only granted the king’s true-born son the right to property.
• The British claimed that the Doctrine was necessary to protect the people from Nawab’s despotic rule and abuse.
• Dalhousie argued that the old system of government was making life miserable for the population.
• Dalhousie made such as policy because he aspired to overthrow the monarchs who claimed to be descended from the Mughals and who asserted their right to hold power.
• With the help of this tactic, the EIC conquered India by claiming the country’s principal states.
• This tactic led to the annexation of several states, including Satara, Udaipur, Sambalpur, Jhansi, Awadh, and Nagpur.

Below given are the states which were annexed by the East India Company due to The Doctrine of Lapse.

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Satara

During the third Anglo-Maratha War in 1818, the Indian kingdom of Satara was founded. In the year 1848, the British annexed it. Because Appa Sahib, the monarch of Satara, passed away in 1848 without leaving a son to take his place, Lord Dalhousie decided to acquire the state of Satara.

Sambalpur

Up until 1817, the Marathas invaded and governed Sambalpur. Following the third Anglo-Maratha war, the British crowned Raja Narayan Singh as the monarch of Sambalpur. When Raja Narayan Singh passed away in 1849, the British conquered the kingdom because he had no masculine heir.

Udaipur

In 1852, Udaipur was annexed. The annexation of Udaipur was eventually overturned by Lord Canning because the board of directors designated it as a protected ally.

Nagpur

Following the Third Anglo-Maratha War, the British formed a subsidiary alliance with the Maratha state. British citizens acknowledged a Child as the state’s ruler. Up until 1830, a British resident presided over the court; the monarch received the power in 1830.The ruler died in 1853 without any heir and that is why the Britishers annexed the kingdom and ignored the adopted son.

Jhansi

Gangadhar Rao was the raja of the Jhansi kingdom. After the king’s death in 1853, the rani adopted Damodar Rao, a son. Damodar Rao’s claim was rejected by the British, who thereafter acquired the state of Jhansi. Rani Laxmi Bai and British soldiers engaged in the renowned battle of Jhansi, which served as the foundation for the Indian revolution of 1857.

Awadh

One of the most significant states that the British seized in 1856 was Awadh. The British insisted that annexing the kingdom of Awadh was their responsibility in order to protect the population from the Nawab’s corrupt rule. British officials deposed Nawan Wajid Ali Shah due to his despotic

The effect of the Doctrine of Lapse

There were various effects of this doctrine which are given below-

• The Indian Rajas were deeply unsatisfied with the British.
• The revolt of the Indian Rajas and nobilities, which assumed a large form as the revolt of 1857, was the most obvious result of Dalhousie’s Doctrine of Lapse.
• The monarch of Nagpur’s adoptive son, Nana Sahib, and the Rani of Jhansi rebelled against the British.
• Lord Dalhousie was held responsible for the revolt of 1857.
• Following the removal of the Doctrine of Lapse in 1857, Queen Elizabeth assumed the title of empress of India.

Summary

The British arrived in India with the intention of trading. They arrived as the East India Company, a trading firm. British people gradually established their monopoly in trade and took control of it. When the Mughal empire collapsed in 1707, India was split up into numerous small kingdoms, and no major power existed. The British viewed the possibility as an opportunity to colonize and annex India. British soldiers fought in numerous battles and won all of them to gain control over India They introduced a number of policies that made sure that they controlled India completely. The Doctrine of Lapse was one such policy wherein the kingdom that did not have any male heir was taken under British rule compulsory and an adopted son was not considered the legal heir of the kingdom.

Frequently Asked Questions

1. What justifications did the British use to annex Awadh?
Ans: The British asserted that Wajid Ali Shah, the monarch of Awadh, was an unfit ruler.

2. Britishers traveled to India when and why?
Ans: British traders from the East India Company first arrived in India around 1600. In order to do business with India. They wanted to buy the raw materials which were abundantly present in India.

3. What measures did the British take to annex Indian princely states?
Ans: The British followed the subsidiary alliance doctrine, which disregarded the kingdom’s own army and forced deploying British troops in their replacement. According to the Doctrine of Lapse only the true son of the king can rule the kingdom and if not, the Britishers gained control.

Introduction

Fish was one of the easily accessible foods that humans in the past often consumed. All around the world, several fish species are consumed as food. It is a significant food that is rich in many nutrients. Different fish, whether freshwater or marine, are used by humans as food. Fish and other sea creatures that are eaten for food are more commonly referred to as seafood.

Fish as food

• Nearly half of the fish consumed today was raised through fish farming, which is practized globally.
• In aquaculture, fish such as tuna, salmon, halibut, cod, and trout are regularly farmed.
• Aquafarms can be constructed as mesh cages submerged in water in addition to concrete enclosures on land.
• Fish farms, however, have the potential to damage the ecology by introducing diseases, pollutants, and invasive species.
• In the coastal parts of India, fish is a common diet.
• Up until 1961, the annual increase in fish consumption worldwide was roughly 3.2% and it has exceeded both the size of the population and the demand for meat of terrestrial animals .
• In addition to increased production, the expansion in consumption has also been influenced by a number of other factors such as-less waste, better use, improved distribution systems, and rising consumer demand.

Fish production

• Fish production, which is known as mariculture or aquaculture where a number of fish are raised and expanded for commercial purposes. Fish can be produced using a number of techniques:
• Fishing capturing: As the name implies, fish in this are collected from many water bodies such as ponds, lakes, rivers etc.
• Fish breeding: It is the practise of raising particular fish species in confined water bodies with great care to achieve optimal yield. This is often referred to as pisciculture or fish farming. It is divided into two further categories:
  • Inland fishery– Fishing in fresh waterbodies such rivers, ponds, lakes, etc. is referred to as inland fishery. The production in this is average. Examples of fishes grown are Rohu, Catla,  carp, etc.
  • Marine fishery– The majority of marine fisheries include fishing in sea and ocean water. Offshore and deep-water fisheries are the two main categories of marine fishery. Fishes grown here are Pomfret, sardines, hilsa,etc.
• Additionally, there are three different approaches to fish farming: extensive, semi-intensive, and intensive.
  • Extensive fish farming– In extensive fish farming, fish productivity is based on the natural productivity of water, it requires large ponds with minimal care.
  • Semi-intensive farming– This method  uses fertilisers to boost the natural productivity of fishes. It has relatively small ponds with a higher fish density.
  • Intensive farming- An extremely well-maintained and well- controlled method of raising fish, in small ponds and tanks, is known as intensive farming.

Making of Regional Cultures

People eat what is easily accessible to them in a particular place. For instance, rice and fish are the two main staple foods of Bengal, which has hot and arid climate. Numerous instances may be found in the literature, sculptures, and artwork of the Bengali people that demonstrate how important fishing has always been to their culture.  For instance, the walls of temples and viharas sometimes have ceramic plaques showing scenes of fish being prepared and transported to markets in baskets. Since fish is a common cuisine in Bengal, Brahmins were allowed to eat some varieties of fish even if their religion forbids doing so. This was found in  a text from the thirteenth century called the Brihaddharma Purana. All of these demonstrate how the regional culture of Bengal developed, due to fish and how eating fish did not become a matter of debate there.

Summary

The consumption of fish as a staple food became common practice since it was easily available. People started using different techniques to capture and breed fish. In general, there are two types of fisheries-  inland fisheries where fish are caught from fresh water, and marine fisheries salt where fish are caught from seas and oceans. A number of variables, including decreased waste and rising consumer demand, contributed to the increase in fishing productivity.

Frequently Asked Questions

1. Why is fish considered a healthy food?
Ans: One of the world’s healthiest foods is fish because it has important nutrients like protein and vitamin D in abundance. Also, omega-3 fatty acids, which are vital for your body and brain, are also found in fish.

2. Which fish has high protein content?
Ans: Fresh tuna contains the greatest protein per gram. It is the most commercially  available and provides the greatest protein per weight (30.7g in a 100-gram serving).

3. Is fish more nutritious than meat?
Ans: Red meats (beef, hog, and lamb) often contain higher cholesterol and saturated (bad) fat than chicken, fish, and plant-based proteins like beans. Saturated fat and cholesterol can increase blood cholesterol levels and aggravate heart disease. Hence as compared to red meat, chicken and fish have less saturated fat and are more healthier.