CBSE Questions for Class 7 Biology Nutrition In Plants Quiz 1 - MCQExams.com

$$\textbf{Correct answer: A}$$ 

$$\textbf{Option (A):}$$ 

$$\bullet$$ The organisms which have the ability to produce their own food are called autotrophs.  

$$\bullet$$ Plants are called autotrophs because they can prepare their own food with the help of photosynthesis. Carbohydrate produced during photosynthesis is used as a nutrient in plant cells.

$$\textbf{Option (B):}$$ 

$$\bullet$$ If an organism is dependent on another organism for its nutrition completely, then they are called parasites. 

$$\bullet$$ The organisms on which parasites are dependent are called the hosts. 

$$\bullet$$ Parasites draw their nutrients directly from the host's body. 

$$\textbf{Option (C):}$$ 

$$\bullet$$ Heterotrophs are those organisms which do not have the ability to prepare their own food.

$$\bullet$$ This is why they depend on autotrophs for their food.

$$\textbf{Option (D):}$$ 

$$\bullet$$ Saprophytes are the specific organisms that feed on the dead and decaying organic matter. 

$$\bullet$$ It breaks down the complex component from the decaying matter to produce the simple molecules.

Hence, the correct answer is correct (A).

• Saprophytes are plants and animals which live on dead material and obtain their nutrients by breaking down organic matter.
• Autotrophs produce their own food using light, water, carbon dioxide and minerals.
• Epiphytes grow on the surface of another plant and derive their moisture and nutrients from the air, rain, water, or from debris accumulating around it. They prepare their own food.
• Parasites live on or in a host organism and get their food from or at the expense of their host.
• So, the correct answer is option D.

• Plants have external cell walls present outside of the cell membrane which provides shape and stability to plants.
• Thus, option A is correct.

• The primary producers present at the first trophic level in an ecosystem are autotrophic.
• These autotrophs perform photosynthesis wherein they use carbon dioxide and water in the presence of sunlight and chlorophyll to produce carbohydrates.
• CO$$_2$$ (Carbon dioxide) + H$$_2$$O (Water) $$\rightarrow$$ C$$_6$$H$$_{12}$$O$$_6$$ (Glucose) + O$$_2$$ (Oxygen)
• So, the correct answer is option C.

$$\textbf{Correct option: }$$ D

$$\textbf{Solution: }$$ 

$$\textbf{Option (a) }$$

$$\bullet$$The nucleus is centrally located in the animal cell and shows the peripheral location in the plant cell. 

$$\bullet$$It is a cellular compartment of the cell containing the genetic material.

$$\textbf{Option (b) }$$

$$\bullet$$The plasma membrane is also known as the cell membrane which surrounds the cells of the organism separating the interior region of the cell from its external environment. 

$$\bullet$$The plasma membrane is called a selectively permeable membrane. It allows the entry and exit of some materials in the cells. 

$$\textbf{ Option (c): }$$

$$\bullet$$Mitochondria is the seat of Krebs cycle where the mitochondrial matrix is involved in the oxidation of pyruvate molecules to produce energy in the form of ATP (adenosine triphosphate).

$$\textbf{ Option (d): }$$

$$\bullet$$The protoplasm excluding the plasma membrane and nucleus is termed as cytoplasm. 

$$\bullet$$Glycolysis of aerobic respiration occurs in the cytoplasm of the cell.

$$\bullet$$Anaerobic respiration occurs in the cell cytoplasm.  

$$\bullet$$This is the site of all cellular activities. 

Hence, the correct option is (d).

$$\textbf{Correct option: }$$ D

$$\textbf{ Solution: }$$

$$\textbf{ Option (D): }$$

$$\bullet$$The process of photosynthesis transfers the element of carbon from CO2 in order to form the biological compounds of the plants which later build the basic structure of the plant. 

$$\bullet$$Therefore, the gas observed in the process of photosynthesis is carbon dioxide. 

Hence, the correct answer is option (D)

• The process by which green plants make their own food  (like glucose) from carbon dioxide and water by using sunlight energy in the presence of chlorophyll is called photosynthesis.
• So, the material is needed by green plants for photosynthesis are chlorophyll, light, water and carbon dioxide.

• The nucleus, cell membrane, and cytoplasm are considered the basic components of any eukaryotic cell since these are present in all eukaryotic cells. 
• Vacuoles are found in both animal and plant cells but size varies.
• Cell walls and chloroplast are absent in animal cells.

• Animals and some plants cannot produce their own food and must obtain their nutrition from outside sources— these plants are heterotrophic. For example - dodder is a parasitic plant that derives nutrition from its host.
  
• Autophytes are plants that can manufacture their own food. 
• Halophytes are plants that grow in extremely saline conditions. 
• Holophytes are the organism that prepares their food by photosynthesis.

Correct Option: D
Explanation:

• The autotropic mode of nutrition is a process in which an organism produces its own food from raw materials.
• The raw material for photosynthesis is water and carbon dioxide. 
•  This process occurs in presence of sunlight, where chlorophyll which is a green-coloured pigment helps in the formation of oxygen and carbohydrate.
• Hence, in the autotropic mode of nutrition, it requires all of the above.

Stomata are small elliptical openings on leaves that contain chloroplasts. They are girdled by two-kidney shaped cells known as guard cells on either side of the stoma. The guard cells possess a thick inner wall and a thin outer covering which control the closing and opening of the pores of stomata.

 So, the correct answer is option B.