Last updated on August 30th, 2023 at 01:57 am
What is a cell?
A: A cell is the smallest unit of life and the building block of all living organisms.
QUE – What is the significance of algae?
According to scientists, algae generate about 87 percent of the world’s oxygen and remove excess carbon dioxide from the atmosphere. They are believed to be an important factor in preventing global warming and climatic changes.
QUE – Differentiate between autotrophs and heterotrophs
Autotrophs are organisms that prepare their food on their own and have chlorophyll. For example, green plants and algae.
Heterotrophs rely on other organisms for nutrition and do not have chlorophyll.es are animals and fungi.
QUE – Define Saprophytic plants:
Saprophytic plants are plants that live on the dead and decaying organic matter of animals and plants. Enzymes are secreted by these plants that break down complex organic matter into simple ones, e.g., Indian pipe, mushrooms
QUE – Describe the different ways that farmers can replenish the soil.
Farmers can replenish the soil in several ways:
- Keeping field fallow
- Crop rotation
- Adding fertilizers
- To grow cover crops
What is an autotrophic mode of nutrition?
The autotrophic mode of nutrition means organisms can produce their own food using sunlight, carbon dioxide, and water, and hence, most plants have an autotrophic mode of nutrition.
Why can’t animals make their own food?
Animals, including humans, cannot make their own food because they do not have the green pigment chlorophyll, which is necessary for the process of photosynthesis.
What is the role of chlorophyll in photosynthesis?
Chlorophyll is necessary to absorb energy from sunlight required for making food by photosynthesis.
What is photosynthesis?
Photosynthesis is the process by which green plants make their own food, such as glucose, from simple inorganic substances like carbon dioxide and water, in the presence of sunlight energy and chlorophyll.
What is necessary for plants to obtain carbon dioxide for photosynthesis?
Plants obtain carbon dioxide for photosynthesis through the tiny pores called stomata present on the surface of leaves. The carbon dioxide gas present in the air enters the leaves of a plant through these stomatal pores.
How do plants obtain water for photosynthesis?
Plants absorb water from the soil through their roots and transport it to the leaves through interconnected pipe-like xylem vessels present throughout the plant.
What is the role of chlorophyll in photosynthesis?
Chlorophyll absorbs light energy from the sun and supplies this energy to the leaves to enable them to carry out photosynthesis to make food.
What are algae, and how do they produce food?
Algae are simple, plant-like organisms that contain chlorophyll and produce food by photosynthesis, just like plants. They differ from plants because they do not have proper roots, stems, and leaves. Algae can be found in patches of slimy, green layers on the surface of ponds, lakes, rivers, and even in stagnant parts of swimming pools.
What is the simplest food synthesized by plants through photosynthesis?
The simplest food synthesized by plants through photosynthesis is a simple carbohydrate called ‘glucose.’
What are the reasons why photosynthesis is important for the existence of life on Earth?
Photosynthesis provides food for animals (including humans) and puts oxygen gas into the air, which animals (including humans) use for breathing and respiration.
What are fertilizers and manures?
Fertilizers and manures contain plant nutrients (or minerals) such as nitrogen, phosphorus, potassium, etc.
Why are fertilizers and manures added to the soil in fields?
Fertilizers and manures are added to the soil in fields to enrich the soil with essential nutrients like nitrogen, phosphorus, potassium, etc., which helps in the growth of crops.
What is NPK fertilizer, and what plant nutrients does it provide?
NPK fertilizer provides Nitrogen (N), Phosphorus (P), and Potassium (K) to the soil in fields.
Why do crop plants grown in fields require nitrogen in maximum amounts?
Crop plants grown in fields require nitrogen in maximum amounts to make proteins.
Why does the soil in fields become deficient in nitrogen after harvest?
The soil in fields becomes deficient in nitrogen after harvest because crop plants take nitrogen from the soil to make proteins.
How can nitrogen-deficient soil become fertile again?
Nitrogen-deficient soil can become fertile again by adding nitrogen-containing fertilizers or by growing leguminous crops in the soil.
Why can’t plants use nitrogen in gaseous form?
Plants need nitrogen in the form of water-soluble compounds like nitrates, which they can absorb through their roots.
What are leguminous plants?
Leguminous plants or legumes are plants like gram (chana), peas, pulses (moong, etc.), and beans which have root nodules containing Rhizobium bacteria.
How do growing leguminous crops in a field benefit farmers?
Growing leguminous crops in a field enriches the soil with nitrogen compounds in a natural way, eliminating the need for farmers to put nitrogen fertilizers in the fields. This saves them a lot of money.
How are living organisms made up of cells?
A: Just like a house is made up of bricks, living organisms are made up of tiny units called cells.
What is the difference between unicellular and multicellular organisms?
A: Unicellular organisms are made up of only one cell, while multicellular organisms are made up of many cells.
What is the function of chloroplasts in plant cells?
A: The function of chloroplasts in plant cells is to contain chlorophyll and make food by the process of photosynthesis.
How are animals and plants different based on their cells?
A: Animals and plants are different based on their cells because they are made up of different types of cells, which results in differences in their appearance and behavior.
