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

The need of tissues in multicellular organisms arises due to ______.

  1. increase in the size of cells

  2. increase in the size of body

  3. increase in the movements of body

  4. increase in the structure of body
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Multicellular organisms develop a complex body structure and the cells are not exposed for long time to the air or water media for exchange of materials. Hence, specialized tissues become necessary to reach all the cells and do the needful activities like gaseous exchange, supply of food, removal of excretory products from all the cells. For this, cells do not increase in size; they are only more in number. Movements increase as a result of efficient working of tissues. Further, there are many multicellular organisms, which are small or minute in size. Hence, tissues are basis of structure and not size. 

Multiple choice

A cell membrane is made of

  1. lipids

  2. phospholipids

  3. bilayer of phospholipids

  4. protein only
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A cell membrane is made up of bilayer of phospholipids. Phospholipids are made up of two fatty acids (long chains of hydrogen and carbon molecules), which are attached to a glycerol 'head'. The glycerol molecule is also attached to a phosphate group, and this is the hydrophilic part of the molecule. The 'tail' end of the fatty acid chains opposite the glycerol is the hydrophobic part of the molecule.

Multiple choice

Which of the following pairs is correctly matched?

  1. Mitochondria – Production of ATP

  2. Golgi body – Synthesis of protein

  3. Lysosome – Synthesis of fats and lipids

  4. Ribosomes – Destruction of foreign substances
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mitochondria – Production of ATP Mitochondria are the energy factories of the cells. The energy currency for the work that animals must do is the energy-rich molecule adenosine triphosphate (ATP). ATP is produced in the mitochondria using energy stored in food.

Multiple choice

Which of the following statements is/are false?

a. Chloroplasts are not found in the root cells of a plant. b. The organelles containing pigments present in the cytoplasm of plant cells are called vacuoles. c. The red colour of tomatoes is due to the presence of red-coloured plastids in their cells.

  1. Only a

  2. Both a and b

  3. Only b

  4. Both b and c

  5. Only c
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the correct option as this statement is false. The organelles containing pigments present in the cytoplasm of plant cells are called plastids.

Multiple choice

Which of following pairs of ‘cell organelle - corresponding function’ is/are incorrectly matched?

  1. Rough endoplasmic reticulum - Protein synthesis
  2. Mitochondria - Lecithin synthesis
  3. Chloroplast - Digestion of food particles

  1. Only 1

  2. Only 2

  3. Only 3

  4. Both 1 and 2

  5. Both 2 and 3
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  1. Rough endoplasmic reticulum is specialised in synthesising proteins.
    1. Some of the enzymes have been located in mitochondria which help in the synthesis of lipids like lecithin from fatty acids and glycerol.
    2. Chloroplast stroma contains enzymes for conversion of carbon dioxide into carbohydrates. Lysosomes help in intracellular digestion of food particles.
Multiple choice

Which of the following cells are bean-shaped?

  1. Muscle cells

  2. Guard cells of stomatal pores

  3. Nerve cells

  4. White blood cells
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Guard cells of stomatal pores are bean-shaped. The guard cells contain chloroplasts, so they can manufacture food by photosynthesis.

Multiple choice

Grana are a part of

  1. mitochondria

  2. chloroplasts

  3. aleurone grains

  4. starch grains
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Chloroplasts contain grana, which are minute particles consisting of a pile of thin double platelets, containing chlorophylls and carotenoids associated with photosynthesis.