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

Epithelium of skin is an example of

  1. columnar epithelium

  2. simple squamous epithelium

  3. glandular epithelium

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

Simple squamous epithelium is found in lining areas where passive diffusion of gases occur. For example, skin, walls of capillaries, linings of the pericardial, pleural and peritoneal cavities, as well as the linings of the alveoli of the lungs.

Multiple choice

The basement membrane

  1. is related with epithelium and endothelium

  2. is a bi-layered structure

  3. can be seen with electron microscope

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

The basement membrane is a thin, fibrous, extracellular matrix of tissue that separates the epithelium (skin, respiratory tract, gastrointestinal tract, etc.), mesothelium (pleural cavity, peritoneal cavity, pericardial cavity, etc.) and endothelium (blood vessels, lymph vessels, etc.) from underlying connective tissue . It is bi- layered.

Multiple choice

Formation of tissues occur as a result of

  1. cell multiplication/division

  2. cell differentiation

  3. inactivation of specific genes

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

Cell multiplication and differentiation are the essential criteria for tissue formation. It also involves changes in the activation of certain genes for morphogenetic development.

Multiple choice

Specialized cells in a tissue

  1. are capable of differentiation

  2. are independent of other cell types

  3. exhibit division of labour

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

Specialized cells in a tissue are independent of other cell types in the tissue.

Multiple choice

All the cells of a tissue have

  1. similar structure

  2. similar function(s)

  3. similar origin

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

In biology, tissue is a cellular organizational level intermediate between cells and a complete organ. A tissue is an ensemble of similar cells from the same origin that together carry out a specific function.

Multiple choice

The intercellular substance in epithelial tissues is mainly composed of

  1. proteoglycans

  2. glycoproteins

  3. triglycerides

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

Glycoproteins are proteins that contain oligosaccharide chains (glycans) covalently attached to polypeptide side-chains. The intercellular substance in epithelial tissues is mainly composed of glycoproteins.

Multiple choice

An epithelium consists of

  1. a single cell layer only

  2. multiple cell layers

  3. basement membrane only

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

An epithelial membrane consists of a continuous sheet of cells, one or more layers thick, which is attached to the underlying connective tissue by a basement membrane. The cells are joined together at specialized regions called cell junctions.

Multiple choice

The term protoplasm includes both the substance within and the cell membrane. Which among the following plant tissues is characterized by the absence of living protoplasm?

  1. Parenchyma

  2. Sclerenchyma

  3. Collenchyma

  4. Xylem

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

Sclerenchyma are simple tissue meant for the mechanical function. It is thick walled and lignified and is characterized by the absence of living protoplasm. The sclerencyma gives mechanical strength to the plant organ, firmness and stiffness to the part of the plant where it is present.

Multiple choice

Match list I and list II.

 
List I
(Cell types in the body of the Sycon) List II
(Characteristics/location of cells types of Sycon)
I. Pinacocytes 1. Cell having whip-like flagellum
II. Choanocytes 2. Cells covering the outer surface of the body
III. Scleroblasts 3. Large amoeboid cells with distinct nucleoli in nuclei
IV. Archaeocytes 4. Cells developing spicules
5. Cells constituting connecting tissues

  1. I - 2, II - 1, III - 4, IV - 3

  2. I - 5, II - 1, III - 2, IV - 4

  3. I - 1, II - 2, III - 5, IV - 3

  4. I - 3, II - 2, III - 1, IV - 4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Sponges belong to phylum porifera and are parazoans.