Tag: Nutrition

Introduction

When people think of algae, they typically picture slimy, green films that grow in still waterways (freshwater and marine). Depending on the species, an Alga may range in size from microscopic to macroscopic and up to a few feet long. Algae are the primary source of atmospheric oxygen that supports many life forms on earth while being blamed for ruining the beauty of transparent waters. The term phycology refers to the study of algae, and phycologists are those who conduct in-depth research on the organisms.

What is Algae?

Algae are cosmopolitan autotrophic eukaryotes having one or more cells that are capable of photosynthetic activity. Organelles like chloroplasts, mitochondria, and the nucleus are membrane-bound in algal cells. 

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Examples of Algae

Some well-known algae include euglenoids, diatoms, kelps, Laminaria, Spirogyra, Volvox, Chara, Fucus, Micromonas, Noctaluca, Chilomonas, Gracilaria, and Chlamydomonas.

Characteristics of Algae

Algae can be multicellular or unicellular. They can also be microscopic as diatoms or large and leafy like kelp. They possess certain qualities that are essential for surviving in predetermined living circumstances.

Habitat: 

• The majority of algal species are found in freshwater and marine aquatic habitats. 
• Different types of water and temperatures allow algae to survive. 
• They can also grow on submerged surfaces and damp rocks. 

Morphology:

• Unlike plants, algae have a simple form. Unicellular algae can organise themselves into filaments or colonies and are either motile or non-motile.
• Kelp-like multicellular algae contain body features that are intended to serve particular purposes.

                                                

Interaction with Environment

Some algae can survive on their own (suspended in water or attached to the substrate), while some species coexist harmoniously with sponges, coral reefs, and fungi. 

Mode of nutrition:

• Chlorophyll is a pigment found in the majority of algae, which are photoautotrophs (photosynthetic pigment).
• The facultative and obligate heterotrophic algae are the only real exceptions. They need carbon substrates from their environment to survive. Some people think that algae exhibit mixotrophy (autotrophy and heterotrophy).

Reproduction

• Mitosis and fragmentation are used in vegetative reproduction. In fragmentation, the damaged component regenerates into a whole body. 
• Spore formation is the means of asexual reproduction. Mature cells divide and produce spores in their cytoplasm. Upon the emergence of favourable conditions, spores transform into new individuals. 
• Sexual reproduction is continued by gametes. Zygotes are created when male and female gametes combine. Female gametes can occasionally grow right into zygotes. This process is called parthenogenesis.

Classification of Algae

Based on their colours, distinct phyla of algae are subdivided. 

• Chlorophyta: Chlorophyll a and b, as well as carotenes, are the pigments found in chlorophyta (green algae). They can be found in colonies, multicellular forms, or unicellular forms. 
• Rhodophyta: Chlorophylls a and d, as well as phycoerythrin and phycocyanin, are the pigments found in Rhodophyta (red algae). They have a crimson appearance because of the phycoerythrin pigment. 
• Phaeophyta: Brown algae, or Phaeophyta, are pigmented with fucoxanthin and chlorophyll a and c. This category primarily includes kelps and seaweeds. 

Types of Algae

Depending on where they live, there are several forms of algae. 

• Cryophilic algae: Grow in snow and ice.
• Thermophilic algae: Grow in hot climates close to hot springs.
• Epizoic algae: Live on the bodies of aquatic creatures like turtles. 
• Edaphic algae: Grow in soil. 
• Epilithic algae: Grow on rocks. 
• Endolithic algae: Inhabit coral reefs. Some call it a symbiotic relationship.
• Corticolous algae: Grow on moist tree trunks.

Chemical Composition of Algae

They contain a variety of pigments, including fucoxanthin, carotenes, phycocyanins, and chlorophyll. Algae have significantly variable cell wall compositions. Cellulose, alginate, carrageenan, agarose, and glycoproteins, including galactans and mannans, are all parts of an algae’s cell wall. Other biomolecules found in algae include lipids, proteins, carbohydrates, nucleic acids (DNA since eukaryotes), and nucleic acids.

Difference between Normal Plants and Algae

Algae, like many sophisticated multicellular plants, use photosynthesis, which explains why chlorophyll is present. They don’t have genuine stems, leaves, or a clearly defined vascular system, which makes them different from plants.

Importance and Uses of Algae 

• They provide between 30 and 50 percent of the oxygen needed for other life forms on Earth. 
• Due to their abilities to gel, become colloidal, and create emulsions, red and brown algal extracts such as alginates, agar, and carrageenans are in high demand in the food sector. 
• Algae are quite sensitive to the condition of the water (pH and composition). They serve as bioindicators of environmental toxicity. 
• From algae that formerly inhabited sea floors, natural gas and crude oil are created. Nowadays, biofuel made from algae is more and more widespread.

Difference between Algae and Fungi

• Fungi are saprophytes. They depend on dead and decaying organic material for nutrients while algae are autotrophs. 
• Algae are very different from fungi, which have chitinous cell walls and no chlorophyll. Both, however, exist as lichens and have a symbiotic connection.
• Algae (often green algae) receive protection from fungi, and fungi receive nutrition from algae.

The Life Cycle of Algae 

• Haplontic life cycle: The plant is haploid throughout. A diploid zygote is created when gametes (which are created by mitosis) combine. The zygote proceeds through meiosis and produces meiospores, which grow into young algae.
• Diplontic life cycle: The body of the sporophytic plant is diploid. The zygote is created by fusing haploid gametes.
• Diplohaplontic life cycle: In the lifetime, haploid and diploid stages are equally dominant. While diploid sporophytes reproduce asexually, haploid gametophytes proliferate sexually.
• Triphasic life cycle: The life cycle alternates between three generations.

• Gametophyte is the dominant stage in a haplontic system. There are two haploid and one diploid generation in the life cycle. 
• Sporophyte, the dominant stage in a diplobiontic organism, There are two diploid and one haploid generation in the life cycle.

Summary

Algae are autotrophic eukaryotes that have one or more cells that are capable of photosynthetic activity. Algae can also be microscopic multicellular (likely leaf-like Giant kelps or unicellular. Chlorophyll is a pigment found in the majority of algae, which are photoautotrophs. Chlorophyll a and b, as well as carotenes, are the pigments found in chlorophyta. Algae are quite sensitive to the condition of the water. They serve as bioindicators of environmental toxicity.

Frequently Asked Questions 

1. Are there Roots in Algae?
Ans. Algae don’t have actual roots. Algae have hold-fast organs in place of roots, which serve as anchors and keep immobile algae attached to a solid substrate.

2. Describe Kelp Forests.
Ans. Brown multicellular algae make up kelp. They live in shallow waters close to the beach. Several small invertebrates and fish breed in dense, thick-grown kelp. Carnivores such as seals and sea lions eat kelp by diving into it, forming an ecosystem.

3. Are Humans Harmed by Algae?
Ans. Algae pose no threat. Some algae create toxic substances that are dangerous to people. Fever, diarrhoea, and skin rashes are the results of direct exposure to these poisons.

4. Are Algae Capable of Producing Biofuel?
Ans. Following numerous stages, the energy-dense oil produced from algae is transformed into different types of fuel. Each species has a different process.

5. What Occurs if the huge Kelp is Removed?
Ans. Algae with their many cells can regenerate. If the environment is right, the damaged component can regenerate into a new body. If not consumed by herbivores, it otherwise deteriorates and decomposes.

Introduction

Agriculture has played a significant role in the rise of human civilization, but organic farming of domesticated species has produced food surpluses that have enabled people to live in urban areas. Agriculture is the art and science of creating and cultivating soil, increasing yields, and keeping animals. Agriculture and farming have historically been essential to human life. The expansion of agriculture and farming was a factor in the development of civilization.

What is Agriculture? 

Agriculture is characterized as the practice of growing plants and animals for human consumption. Various parameters need to be considered in agriculture, such as the type of crop, soil characteristics, environment, and so forth. Farmers decide which crop should be cultivated at what time and location based on these parameters. Aside from that, reasonable soil, environment, and season are insufficient to produce a high-quality product. It necessitates several tactics that need to have been used.

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Importance of Agriculture

Social and Economical Aspect:

• Agriculture increases the availability of food, which improves population nutrition and promotes population health. 
• A small number of people cannot do agriculture. Each of its processes requires the input of numerous persons. Consequently, this results in the creation of jobs.

Environmental Aspect:

• Waste management depends heavily on agriculture. The biodegradable wastes can be transformed into manure, which the plants can use as a source of food.
• With the right treatment, bare soil can be turned into crops, ensuring agriculture’s efficient use of land resources. 
• It significantly contributes to preserving the microclimate of any location and raises the standard of the ecosystem as a whole.

What are the Basic Agricultural Practices?

Those consecutive actions that are taken to guarantee the proper production of crops are referred to as “agricultural practices.” To guarantee a yield of great quality, this must be done. The next section has a quick discussion of the steps.

Steps of Agricultural Practices

• Preparation of soil:
• • It is crucial to prepare the soil to make sure it is rich, well-drained, well-aerated, uniform, and can hold enough moisture. This stage is essential because the soil must survive numerous adverse situations. After all, it is exposed to them. 
  • Typically, the preparation is carried out with the aid of various tools, such as a hoe and a plow.
  • To provide the best aeration, the soil must be dug out and loosened.
  • To spread the dirt equally and avoid lumping, leveling is done after plowing. 
  • Finally, there is a chance that the soil has run out of nutrients, which could be bad for plant growth. Manure and fertilizers are thus applied to restore it.
• Seed selection and sowing

• Choosing the right seeds is crucial to getting a good crop. 
• A quality seed, also known as an HYV or High Yielding Variety seed, guarantees improved plant growth, increased disease resistance, and increased yield. 
• The chosen seeds must be planted in the prepared field after being chosen. 
• Sowing is the distribution and burying of seeds into the soil, whether by hand or with the aid of machines.
  
• Irrigation
• To meet the crops’ water needs, the best possible amount of water is applied to the soil where the crops are growing. 
• A source of water, such as ponds, wells, rivers, etc., is typically supplied by a variety of channels, such as canals or pipelines.
• Crop maintenance
• • Considering that the crops must grow for a long period and are exposed to the elements, they need some maintenance. 
  • In essence, they can be destroyed by the numerous pests, birds, rodents, etc. that are likely to attack them.
  • Unwanted plants known as weeds can encroach on cropland and compete with crops for nutrients, stifling the development of crops. 
  • To protect them, it is therefore imperative to apply weedicides, insecticides, etc. 
  • To stop bird assaults, farmers frequently construct scarecrows.
• Harvesting
• • It is the process of gathering the crop’s valuable components, and it is typically carried out after the crop is fully mature and has reached its ideal development stage. 
  • It can be carried out manually with implements like a sickle or with the aid of machines.
• Storage

• In this last step, the harvested goods are moved to the granaries or storehouses before being distributed to the market. 
• To prevent desiccation, it is essential to dry the items before storing them, especially grains and pulses.
• The items are additionally fumigated to deter rodent and pest infestations.

What are Sustainable Agricultural Practices?

The concept of sustainability is the prevention of resource depletion by the adoption of specific actions that preserve both the health of the natural world and the future of humanity. Some of the measures taken in agriculture are discussed below.

• Making sure that soil is properly used and prepared to prevent erosion.
• Reducing water use through the application of new methods and tools.
• Drop-by-drop watering is done with drip irrigation, which is time-controlled. In the revolutionary practice of hydroponics, nutrients are dissolved in water and fed to plants to provide them with nutrition.
• The use of biodynamic farming methods is recommended.
• Crop rotation proposes that different crop types should grow in a specific region.
• Promoting the expansion of the pests’ natural predators to reduce the need for pesticides, weedicides, and other chemicals.

Summary

Agriculture is characterized as the practice of growing plants and animals for human consumption. Agriculture increases the availability of food, which improves population nutrition and promotes population health. The biodegradable wastes can be transformed into manure, which the plants can use as a source of food. It is crucial to prepare the soil to make sure it is rich, well-drained, well-aerated, uniform, and can hold enough moisture.  Crop rotation proposes that different crop types should grow in a specific region.

Frequently Asked Questions 

1. Define Pesticides?
Ans. Pesticides are a class of chemicals that include insecticides, herbicides, and fungicides that are used to control pests (harmful organisms) in agriculture. Examples include glyphosate, DDT, etc.

2. Why is it no Longer Advisable to use Fertilizers Today?
Ans. Fertilizers are extremely damaging to the environment. Overuse of fertilizers creates contaminants that travel via the water and air. They obliterate the water and soil microorganisms. They contribute to a phenomenon known as “biomagnification.” So it is not recommended to use more fertilizers.

3. Which Crop Diseases are Prevalent?
Ans. Common bacterial diseases include fire blight, necrosis, and Granville withering. Exfoliation, wheat black rust, and other common fungi-caused illnesses are only a few examples.

 4. What is the Indian “Green Revolution”?
Ans. With the use of technology, agricultural systems in India were transformed into modern industrial systems during the Green Revolution of the 1960s. This period included the use of HYV, mechanized farming tools, irrigation systems, fertilizers, and pesticides.

5. Define Genetically Modified Crops?
Ans. Genetically modified crops are those whose genomes have undergone genetic engineering modifications to exhibit desired features like higher nutrient production and pest resistance. For example, BT brinjal.