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 botany caskets of life the cell structure multicellular organisms number and shape of cells

Different cells have different sizes. Arrange the following cells in ascending order of their size and select the correct option:


(i) Mycoplasma                  (ii) Ostrich egg
(iii) Human RBCs              (iv) Bacteria

  1. (i) $\rightarrow$ (iv) $\rightarrow$ (iii) $\rightarrow$ (ii)
  2. (i) $\rightarrow$ (iii) $\rightarrow$ (iv) $\rightarrow$ (ii)
  3. (ii) $\rightarrow$ (i) $\rightarrow$ (iii) $\rightarrow$ (iv)
  4. (ii) $\rightarrow$ (ii) $\rightarrow$ (i) $\rightarrow$ (iv)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • The smallest cell is Mycoplasma (0.1-0.5$\mu m$). 
  • Bacterial cell measures 3-5$\mu m$ in length. 
  • Erythrocytes are 6-8$\mu m$ in diameter. 
  • The larges cell is the egg of Ostrich.
Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Cells regulate their activity through 

  1. Flow of energy

  2. Flow of material

  3. Flow of information

  4. Flow of smoke
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cells in your body get energy from the foods that are eaten, such as glucose (a sugar). Cellular respiration converts glucose and oxygen into water, carbon dioxide and usable form of energy called ATP (this stands for adenosine triphosphate).

So the correct answer is 'option A'.

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

The mature cells in the mammalian body, i.e., RBC loses their capacity for

  1. Aerobic respiration

  2. DNA replication

  3. RNA synthesis

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Nucleus is double membrane covered protoplasmic body that contains hereditary information. A nucleus is absent in some mature cells like mammalian RBCs and sieve tube cells in plants. They are called as enucleate cells. In mammals, erythrocytes also lose all other cellular organelles such as their mitochondria, Golgi apparatus and endoplasmic reticulum. As a result of not containing mitochondria, these cells use none of the oxygen they transport; instead they produce energy by glycolysis of glucose and lactic acid fermentation of the resulting pyruvic acid.

Thus, the correct answer is option D.

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Which of the folwing statement can be related to 'It is said that every multicellular organism has come from a single cell'?

  1. Every organism starts its life from a zygote, a single cell.

  2. Cells divide to produce cells of their own kind and thus, all cells of the body come from the pre-existing cells.

  3. Both A and B.

  4. None of the above.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

All the multicellular organisms start their life with a single cell (zygote). Later, it is divided and differentiated into different cell types in multicellular organisms. Cells are capable of dividing to form their own kind of cells. Thus, all cells of the body come from the pre-existing cells. Thus, the correct answer is option C.

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Cells of multicellular organism are usually________________

  1. Triangular

  2. Rectangular

  3. Polyhedral

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cells of unicellular organisms are usually spherical due to surface tension. 
Cells of the multicellular organism are usually polyhedral. Because polyhedral cells have more neighbors which means more intercellular exchange can occur. Also, the polyhedral group of cells resists stretching to a more extent. 

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Few genes are found in all types cells

of differentiated multicellular organisms of high

class. It is called

  1. Key genes

  2. Core genes

  3. House keeping genes

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Core genes refer to the genes present in all the cells of an organism.
Housekeeping genes are those genes which are always expressed in a cell and code for various proteins that are required for the normal functioning and sustenance of cell. These genes are expected to maintain constant expression levels in all cells and at all conditions. Lethal gene is the gene that generally formed by the mutation and causes the death of the organisms.
Thus, the correct answer is option B.
Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

A multicellular organism possesses

  1. Differentiated cells.

  2. Undifferentiated cells.

  3. Dedifferentiated cells.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A multicellular organism attains its multicellularity from a single cell. Single totipotent cell undergo number of mitotic and meiotic divisions to give rise to a multicellular structure where cells undergo differentiation to a particular function. Some of the cells are undifferentiated such as stem cells which can give rise to any type of cells of the body. Also multicellular organisms undergoes dedifferentiation process where a differentiated cell revert back to totipotent cell and can again differentiate to a particular type of cell witha particular function. So Multicellular organisms posses all these type of cells so Answer D is correct.

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Functionally important dead cells are

  1. Cork cells.

  2. Tracheary elements.

  3. Endothelial cells.

  4. Both A and B.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cork cells (phellem) are dead at maturity and provide protection. Tracheary elements (xylem vessels and tracheids) are also dead at maturity and function in water transport. Both are functionally important dead cells.

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Cells are composed of highly independent and randomly interacting components.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The cell is a basic biological unit of living organisms.

A cell contains different membrane-bound organelles which are structural and functional units constructed from several macromolecules bonded together.A typical animal cell contains, the nucleus which possesses genetic material DNA, mitochondria to generate energy, nucleolus in the nucleus to produce ribosomes, ribosomes to produce proteins and endoplasmic reticulum which packages and transports proteins, sugars and lipids to Golgi bodies to distribute them through lysosomes to different parts of the cell. All organelles are anchored in cytoplasm of the cell and work in harmony with each other.
Therefore the option B is correct.

Multiple choice botany caskets of life the cell structure multicellular organisms number and shape of cells

Name the kinds of cells found in the following places:

  1. Surface of the human skin

  2. Salivery gland

  3. Brain

  4. Inner lining of the wind pipe
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

A. merkel cells, keratinocytes, melanocytes andLangerhans cells.

B.epithelial cells, mucous cells.

C. astrocytes, oligodendrocytes andependymal cells.

D. goblet cells, columnar epithelial cells.