Tag: need of family planning

Questions Related to need of family planning

The sequence of cell cycle is

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. S,M,G$ _{1}$, and G$ _{2}$

  2. G$ _{1}$,G$ _{2}$,S and M

  3. G$ _{1}$,S,$G _{2}$, and M

  4. M,G$ _{1},$,G$ _{2}$ and S

Show answer
Correct Option: C
Explanation:
  • Cell enters cell cycle at G$ _1$ (First Gap) phase, where the cell grows larger, doubles organelles and synthesizes proteins, enzymes and all other biochemical molecules required for efficient completion of cell division.
  • Then cell enters S (synthesis) phase, where cell synthesizes a complete copy of the genomic DNA inside the nucleus. It also duplicates centrosome which is required for separation of DNA to opposite poles during mitosis.
  • Then cell enters the G$ _2$ (Second Gap) phase, where cell grows more and produces more proteins and organelles required for mitosis. Cell also reorganize its contents for mitosis to occur. G$ _2$ phase also acts as a checkpoint to ensure that the cell is ready for mitosis.
  • The end of G$ _2$ phase is the beginning of M (Mitosis) phase, where the real cell division occurs. The cell divides its doubled DNA and cytoplasmic contents to form two daughter cells.
So, the correct option is 'G$ _1$, S, G$ _2$and M'.

The various phases of the cell cycle will be affected by limiting growth factors like

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. Sufficient nucleotides

  2. Temperature

  3. Nutrients

  4. All of the above

Show answer
Correct Option: D
Explanation:

G1 phase and the other subphases of the cell cycle may be affected by limiting growth factors such as nutrient supply, temperature, and room for growth. Sufficient nucleotides  and amino acids must be present in order to synthesize mRNA and proteins. Physiological temperatures are optimal for cell growth. In humans, the normal physiological temperature is around 37 C. Therefore, the correct answer is option D.

Generation time represents period of 

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. Cell cycle

  2. Interphase

  3. M-phase

  4. S-phase

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Correct Option: A

The correct order of the various phases of eukaryotic cell cycle is ____________.

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. G${ _1}$ to S to G${ _2}$ to M to cytokinesis

  2. G${ _1}$ to G${ _2}$ to M to S to mitosis

  3. G${ _1}$ to G${ _2}$ to S to M to karyokinesis

  4. S to G${ _1}$ to G${ _2}$ to M to cytokinesis

  5. G${ _2}$ to M to S to G${ _1}$ to cytokinesis

Show answer
Correct Option: A

Identify, the correct sequence of the cell cycle events.
I. Nuclear membrane dissolves
II. Cell size increases
III. Two daughter cells form
IV. DNA replicates

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. I, IV, II and III

  2. I, IV, III and II

  3. II, I, IV and III

  4. II, IV, I and III

  5. IV, II, III and I

Show answer
Correct Option: D
Explanation:

The cell cycle includes a series of events, that take place  in a cell which leads to the duplication of DNA and division of cells to form two daughter cells. This takes place in three different  periods and can be referred to as Interphase , Mitotic phase(M) and cytokinesis. While during the interphase or the initial phase, the cells grow in size and is ready for division, during the mitosis, the DNA starts duplicating, the nuclear membrane dissolves and the cells starts its division process to give rise to  two distinct daughter cells. Cytokinesis is the stage during which the two daughter cells are formed and separated.
So, the correct answer is option D.

Mitotic cell cycle is divided typically into four phases, $G _1$, S, $G _2$ and M. Considering a mitotic cycle time of $18$ hours, the distribution of period of time(in hours) for each of these phase will be. $G _1$S$ _2$M.

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. $1, 3, 5, 9$

  2. $9, 1, 3, 5$

  3. $9, 5, 3, 1$

  4. $3, 5, 9, 1$

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Correct Option: A

Yeast complete cell cycle in _____________.

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. 30 minutes

  2. 60 minutes

  3. 90 minutes

  4. 120 minutes

Show answer
Correct Option: C
Explanation:

One cell cycle of yeast is almost 90 minutes and a human cell takes almost 24 hours to divide by mitosis therefore by calculations it seems that a yeast can perform mitosis almost 16 times in the time of 1 division of a human cell.

Thus 90 is correct option. 

Cell cycle was discovered by 

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. Farmer and Moore

  2. Prevost and Dumas

  3. Howard and Pelc

  4. Remak

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Correct Option: A

In a culture of E.coli the cell population increased from $1.5 \times 10^6$ cells /ml to $ 12 \times 10^6$ cells/ml in 36 minute.The generation time is 

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. 6 mt

  2. 9 mt

  3. 12 mt

  4. 18 mt

Show answer
Correct Option: C
Explanation:

At the start, the culture of E. coli has cell population of 1.5 X 10$^6$ cells/ml. After first generation, it will be doubled, that is 3 X 10$^6$ cells/ml. After second generation, it will be 6 X 10$^6$ cells/ml. After third generation, it will be 12 X 10$^6$ cells/ ml. It is given that for a cell population to increase from 1. 5 X 10$^6$ cells/ml to 12 X 10$^6$ cells/ml, it takes 36 minutes. It means, for 3 generation, it takes 36 minutes. So, its generation time is 36/3 = 12.

Thus, the correct answer option C.

Cdk which control progression through cell cycle check points are fully activated by.

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. Binding to cyclin

  2. Phosphorylation by Cdk activating protein kinase

  3. Binding to cyclin, plus phosphorylation by Cdk activating protein kinase

  4. Phosphorylation by tyrosine kinase

Show answer
Correct Option: C
Explanation:

Through phosphorylation, Cdks signal the cell that it is ready to pass into the next stage of the cell cycle. As their name suggests, Cyclin-Dependent ProteinKinases are dependent on cyclins, another class of regulatory proteins. Cyclins bind to Cdks, activating the Cdks to phosphorylate other molecules.

So, the correct option is ‘binding to cyclin, plus, phosphorylation by Cdk activating protein kinases’.