Biology ยท Science General

Cell Biology and Structure

3,221 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

Excretory products of plants are __________.

  1. lignin and cellulose

  2. cellulose and resin

  3. resin and gums

  4. gums and lignin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Resins and gums are the excretory products of plants that are stored in xylem (water and minerals conducting channel). Resin is a viscous, thick and sticky liquid, secreted by some plants especially by coniferous trees. Gums are mucilaginous substances secreted by the plants. Cellulose is the most abundant component of plant cell walls. Lignin is a component of cell walls, which binds cellulose fibres, confers strength and hardens the wood.

Multiple choice

Which of the following statements is/are false?

a. All cells are capable of carrying out basic functions like nutrition, respiration, growth and reproduction. b. All the cells use different mechanisms for energy metabolism. c. In multicellular organisms, cells are specialised to perform different functions of the body so that there is a division of labour within the cell.

  1. Only a

  2. Only a and b

  3. Only b

  4. Only 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. All the cells use same basic, and not different mechanisms for energy metabolism.

Multiple choice

In a multicellular organism, the shape of a cell depends upon the

  1. functional adaptations

  2. surface tension

  3. viscosity of the protoplasm

  4. All of the above

  5. mechanical action exerted by the adjoining cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct option as in a multicellular organism, the shape of a cell depends upon functional adaptations, surface tension, viscosity of the protoplasm and mechanical action exerted by the adjoining cells. In a multicellular organism, the shape of a cell depends upon the mechanical action exerted by the adjoining cells. But, other factors are also responsible like functional adaptations, surface tension, viscosity of the protoplasm, etc.

Multiple choice

Which of the following cells are discoidal?

  1. Pigment cells of the skin

  2. Red blood cells

  3. Nerve cells

  4. Smooth muscle fiber cells

  5. Chromatophores
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is the correct option. Red blood cells are discoidal in shape.

Multiple choice

The process by which the membrane of a vesicle can fuse with the plasma membrane and extrude its contents to the surrounding medium is called ____________.

  1. phagocytosis

  2. photocytosis

  3. endocytosis

  4. exocytosis

  5. receptor-mediated endocytosis
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct option. The process by which the membrane of a vesicle can fuse with the plasma membrane and extrude its contents to the surrounding medium is called exocytosis.