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

To what does the term granum refer?

  1. A stack of thylakoid membrane structures

  2. A central fluid filled space in the chloroplast

  3. A flattened disk or sac in the chloroplast

  4. The double membrane of the chloroplasts

  5. The cytochrome system in the membranes of the thylakoids
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A granum is a stack of thylakoid disks within the chloroplast, functioning as the site for the light-dependent reactions.

Multiple choice

Restorer gene for fertility is present in the ______.

  1. ribosome

  2. nucleus

  3. endoplasmic reticulum

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

Restorer genes are nuclear genes that suppress the effects of cytoplasmic male sterility, allowing the plant to produce functional pollen. Therefore, they are located in the nucleus.

Multiple choice

Which of the following sentences about epithelial tissue is false?

  1. Cells are densely packed together with minimal amount of intercellular substance.

  2. It is avascular.

  3. It is richly supplied with nerve fibres.

  4. It gets nutrients by absorption from underlying connective tissue.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

It gets nutrition by diffusion from underlying connective tissue. Thus, it is the answer as it is a false statement about epithelial tissue.

Multiple choice

A false appearance of arrangement of nuclei is observed in

  1. stratified epithelium

  2. pseudostratified epithelium

  3. simple ciliated epithelium

  4. simple cuboidal epithelium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In pseudostratified epithelium, the nuclei appear to be arranged in more than one layer. This is a false appearance.

Multiple choice

In comparison to the plants, animals do not have a demarcation between the dividing and non-dividing regions because

  1. cell growth in animals is uniform

  2. cell growth in plants is uniform

  3. Cell growth in animals is localised

  4. Cell growth in animals is non-uniform

  5. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The growth in plants is limited to certain regions, thus meristmatic tissue or dividing tissue in plants is localised to these regions. However, cell growth in animals is more uniform. So, there is is no demarcation of dividing and non-dividing regions in animals.