Biology · Science General

Cell Biology and Structure

3,062 Questions

Cell biology focuses on the structure and function of cellular organelles. Key topics include cellular respiration, DNA inheritance, and energy production. These fundamental biology concepts are crucial for medical entrance and state service examinations.

Cell organelles functionsCellular respiration sitesDNA and ribosomesAnimal cell structurePlant cell components

Cell Biology and Structure Questions

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Which one of these is not correct regarding peroxisomes?

  1. Single membrane bound organelles
  2. Perform photorespiration in $C _{3}$ plants

  3. Take part in synthesis and storage of lipids
  4. Protect a cell from the toxic effects of $H _{2}O _{2}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
SER takes part in synthesis and storage of lipids. Peroxisomes are the single membrane bound cell organelles, which perform photorespiration in association with chloroplasts and mitochondria. They protect the cell from the toxic effects of $H _{2}O _{2}$.
So, the correct answer is 'Take part in synthesis and storage of lipids'.
Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Which of the following statements regarding spherosomes is not correct?

  1. Abundant in the endosperm cells of oil seeds

  2. Bounded by a single membrane

  3. Take part in synthesis and storage of lipids

  4. Take part in photorespiration
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Sphaerosomes are small cell organelles bounded by single membrane which take part in storage and synthesis of lipids. Sphaerosomes occur abundantly in the endosperm cells of oil seeds. Sphaerosomes of some tissues (e.g., tobacco endosperm, maize root tip) contain hydrolytic enzymes. Therefore, they are considered to have lysosomic activity. They donot take part in photorespiration.
So, the correct answer is 'Take part in photorespiration'.
Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Cell organelle extracted from endosperm of germinating castor beans are

  1. Glyoxysomes

  2. Vacuoles

  3. Mitochondria

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Glyoxysomes are microbodies which contain enzymes for $\beta - oxidation$ of fatty acids and glyoxylate pathway. They are considered to be special peroxisomes. They occur abundantly in germinating endosperm cells of oil seeds.
So, the correct answer is 'Glyoxysomes'.
Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

All the following statements are correct, except

  1. Peroxisomes are quite common in the photosynthetic cells. Their number can be 70-100 per mesophyll cell, wherein they interact with mitochondria and chloroplasts to take part in photorespiration

  2. Glyoxysomes are numerous in the the endosperm of wheat.

  3. The ER-bound ribosomes synthesise secretory membrane and lysosomal protein

  4. Ribosomes when associated with ET are attached with their 60S sub-unit
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Peroxisomes are cytoplasmic organelles that play a central role in break down of fatty acids and other oxidation reactions in the cell.

So, the correct option is 'Peroxisomes are quite common in the photosynthetic cells. Their number can be 70-100 per mesophyll cell, wherein they interact with mitochondria and chloroplasts to take part in photorespiration'.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Which of the following organelle is associated with triglyceride metabolism?

  1. Peroxisome

  2. Glyxosome

  3. Sphaerosome

  4. Transosome
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 Peroxisomes are cell organelles that are involved in lipid or triglyceride metabolism. They are bound by a single membrane and are present in the cytosol.

So, the correct answer is 'Peroxisome'.
Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Cell organelles taking part in photorespiration are ____________.

  1. Peroxisomes

  2. Glyoxisomes

  3. Dictysomes

  4. Endoplasmic reticulum
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Peroxisomes are membrane-bound organelles in eukaryotes. Photorespiration is a light-dependent process that takes place in mitochondria in which oxygen is absorbed and carbon dioxide is released. It is counter-productive to photosynthetic carbon dioxide fixation and decreases plant productivity. But it also provides protection against conditions caused by high light intensity, drought, and salinity.  Thus the correct answer is option A.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Read the given statements and select the correct option.


Statement 1: Peroxisomes are involved in photorespiration of the plant cells and help in the lipid metabolism of animal cells.
Statement 2: They are the cell's garbage disposal system.

  1. Both statements 1 and 2 are correct

  2. Statement 1 is correct but statement 2 is incorrect

  3. Statement 2 is correct but statement 2 is incorrect

  4. Both statements 1 and 2 are incorrect
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Peroxisomes are found in photosynthetic cells and perform photorespiration. They also take part in lipid metabolism. Lysosomes are the cell's garbage disposal system and not the peroxisomes.

So, Statement 1 is correct and statement 2 is incorrect.

Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Glycolate cycle occurs in?

  1. Lysosomes

  2. Ribosomes

  3. Glyoxysomes

  4. Peroxisomes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
In plants, the glyoxylate cycle occurs in specialized cells called glyoxysomes. During germination, the seeds used lipids as the energy source to form the shoot. Acetyl CoA proceeds through glyoxylate cycle and released succinate as the end product. This cycle occurs only in glyoxysomes, which are lying in the fat storage tissues of germinating seeds. 

Hence, the correct answer is option C.
Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

Which one of these is not correct regarding peroxisomes?

  1. Single membrane bound organelles
  2. Perform photorespiration in ${C} _{3}$ plants

  3. Take part in synthesis and storage of lipids
  4. Protect a cell from the toxic effects of ${H} _{2}{O} _{2}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
SER takes part in the synthesis and storage of lipids. Peroxisomes are the single membrane bound cell organelles, which perform photorespiration in association with chloroplasts and mitochondria. They protect the cell from the toxic effects of $H2 _O$. 
So, the correct answer is 'Take part in the synthesis and storage of lipids'.
Multiple choice bio-chemistry structure and function of cell organelles microbodies living organisms and energy production single membrane bound organelles

_______ are the microbodies, which take part in glyoxylate pathway, bounded by a single membrane and are usually present in germinating fatty seeds.

  1. Glyoxysomes

  2. Peroxisomes

  3. Sphaerosomes

  4. Lysosomes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Glyoxysomes are microbodies which contain enzymes for $\beta$-oxidation of fatty acids and glyoxylate pathway. They are considered to be special peroxisomes. They occur abundantly in gerrminating endosperm cells of oil seeds.

Multiple choice

Where are structural carbohydrates found in the plant?

  1. In the cell wall

  2. In the cell organelles

  3. In the cell nucleus

  4. In the cell membrane
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Structural carbohydrates, such as cellulose and hemicellulose, provide rigidity to plants. These are found primarily in the cell wall, which gives the plant its structure.

Multiple choice

Humans and many other animals are made up of 4 basic types of tissue:

  1. nervous, epithelial, connective, and muscle

  2. nervous, epithelial, carbohydrates, and nucleic acids

  3. lipids, proteins, carbohydrates, and nucleic acids

  4. lipids, proteins, connective, and muscle
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The four primary tissue types in animals are epithelial, connective, muscle, and nervous tissue.