Tag: mitosis

Questions Related to mitosis

Angiotensinogen is a protein secreted by

  1. Juxtaglomerular cells

  2. Macula densa cells

  3. Endothelial cells

  4. Liver cells


Correct Option: D
Explanation:
Angiotensinogen is a plasma protein produced and secreted by liver cells. It is a sole precursor of all angiotensin peptide. Juxtaglomerular cells secrete renin which acts on angiotensinogen to release angiotensin I and then it is converted to angiotensin II by the action of enzyme angiotensin-converting enzymes.
So, the correct answer is 'Liver cells'.

Calcium occurs in

  1. All body cells

  2. Bones and teeth

  3. Cells of respiratory system

  4. 3% of mineral content


Correct Option: A

Division of the nucleus is called ..........

  1. Cytokinesis

  2. Karyokinesis

  3. Replication

  4. None of the above


Correct Option: B
Explanation:

Division of the nucleus is called karyokinesis. The process of partition of a cell's nucleus into the daughter cells during cell division is called karyokinesis. All the changes in a nucleus that occur during cell division are collectively termed as karyokinesis. It has four stages prophase, metaphase, anaphase, and telophase.

So the correct answer is "Karyokinesis".

All nuclear changes that occur during mitotic cell division are collectively called as

  1. Karyokinesis

  2. Cytokinesis

  3. Recombination

  4. Both A and B


Correct Option: A
Explanation:

All nuclear changes (Prophase, metaphase, anaphase, and telophase) that occurs during mitotic cell division are collectively called as karyokinesis. Mitotic cell division consists of two steps. The first step is karyokinesis where nuclear division takes place which is followed by cytokinesis i.e the division of cytoplasm takes place and individual daughter cells are formed. So, the correct answer is 'Karyokinesis'.

The epithelial cells lining the stomach of vertebrates are protected from damage by HCl because.

  1. HCl is too dilute

  2. The epithelial cells are resistant to the action of HCl

  3. HCl is neutralized in the stomach

  4. The epithelial cells are covered by mucus


Correct Option: D
Explanation:
The epithelial cells lining the stomach of vertebrates are protected from damage by HCl because 'the epithelial cells are covered by a mucous secretion'.
So the correct option is D.

Epithelial cells serves the function of protection, secretion and absorption and is separated from the other tissues below by a _____.

  1. Basal lamina

  2. Lamina propria

  3. Connective tissue

  4. Stratum granulosum


Correct Option: B

Cell cycle was divided into  four stages i.e. G$ _1$, S, G$ _2$, M by

  1. W. Flemming

  2. Strass burger

  3. Howard and Pelc

  4. Farmer


Correct Option: C
Explanation:

Howard and Pelc divided cell cycle in four stage. The cell cycle is an ordered set of events, culminating in cell growth and division into two daughter cells. Non-dividing cells not considered to be in the cell cycle. The stages  are G$ _1$-S-G$ _2$-M. The G$ _1$ stage stands for "GAP 1". The S stage stands for "Synthesis". This is the stage when DNA replication occurs. The G$ _2$ stage stands for "GAP 2". The M stage stands for "mitosis", and is when and cytoplasmic division occur.

Which of the following stage of M-phase is considered as tetraploid stage?

  1. Anaphase of mitosis

  2. Anaphase-I of meiosis

  3. Metaphase-II of meiosis

  4. More than one option is correct


Correct Option: A
Explanation:

In mitosis DNA content is doubled during S phase resulting in 2n chromosomes having two chromatids. These 2 chromatids of 2n get arranged at metaphase plate in metaphase. And in anaphase, the 2 chromatids of 2n chromosomes are separated from each other . so the cell during this phase becomes 4n.

So, the correct answer is 'Anaphase of mitosis'.

A cell divides in order to?

  1. Maintain size of nucleus

  2. Maintain bulk of cytoplasm

  3. Maintain balance between bulk of cytoplasm and nucleus

  4. Maintain size of chromosomes


Correct Option: A
Explanation:

Early in the history of biology, scientists believed cells arose spontaneously. With the development of cell theory, people finally realized that only cells can beget other cells. In fact, two categories that define something as living or not are growth and reproduction, both of which cell division accomplishes. Cell division, also called mitosis, occurs in all living things. As living things grow, some cells die or become damaged and need replacements. Some single-celled organisms use a type of mitosis as their only form of reproduction. In multicellular organisms, cell division allows individuals to grow and change by expanding the number of total cells. The division of the nucleus is equal during cell division. This ensures the characteristic of both parent cell in daughter cells and restores the size of the nucleus.


So, the correct option is 'maintain size of nucleus'

Chromosome decondensation, crossing over synapsis formation, nucleolus disappear, chromosome separation, astral ray formation, centriole duplication. How many of these are observed in prophase of meiosis-1 and mitosis both? 

  1. Three

  2. Four

  3. Two

  4. Five


Correct Option: A
Explanation:

Mitosis is equational division and meiosis is reductional division. Both consists of 4 phases, namely prophase, metaphase, anaphase and telophase. Prophase is the first phase of both mitosis and meiosis I. During this phase, the chromatin condenses and forms visible chromosomes. The mitotic spindle begins to form, nucleolus disappears, the nuclear envelope disappears. 

Crossing over synapsis formation occurs during prophase I of meiosis I only. Astral ray formation takes place during metaphase. 
Centriole duplication occurs during the S phase of the cell cycle.
Thus, the correct answer is 'Three.'