Cell Division: Introduction

Q. Which one is the longest phase of cell cycle?

1. $G_{1-}$ Phase
2. $G_{2-}$ Phase
3. Prophase
4. Telophase

Q.

What happens in the S phase?

Q. The onion cell has 16 chromosomes before S phase. How many chromosomes are present in the onion cell after S phase?

1. 32 chromosomes
2. 16 chromosomes
3. 8 chromosomes
4. 64 chromosomes

Q. A chromosome consists of _____ chromatid (s), _______ centromere(s).

1. 1, 1
2. 2, 1
3. 2, 2
4. 1, 2

Q.

Which of the following correctly represents the number of autosomes and allosomes in human beings?

1. (21+2) pairs

2. (22+1) pairs

3. (19+4) pairs

4. (2+21) pairs

Q.

Given below are the sets of five terms, rewrite the terms in a logical sequence:

Karyokinesis, S-phase, cytokinesis, G1-phase, G2-phase (cell cycle).

Q. How many chromatids are there in a chromosome after S phase?

1. One
2. Two
3. Three
4. Four

Q. Sort the events of meiosis II in the correct order.

1. Prophase II
2. Metaphase II
3. Anaphase II
4. Telophase II

Q. The division of cytoplasm is known as

1. Karyokinesis
2. Synapsis
3. Mitosis
4. Cytokinesis

Q. Look at the figure given below. The number given inside the circle represents the number of chromosomes in the cell at that point. Fill in the blanks for (i), (ii) and (iii) using the option that fits best.

1. (i) - 40; (ii) - 20; (iii) - 10
2. (i) - 40; (ii) - 10; (iii) - 10
3. (i) - 20; (ii) - 10; (iii) - 10
4. (i) - 40; (ii) - 20; (iii) - 20

Q. State the function of the following:
Centromere:

[1 Mark]

1. The point at which Sister chromatids join
2. Helps in the division of centrioles
3. Helps in the formation of spindle fibres
4. Helps in the nuclear membrane formation

Q.

The chromosomes are get aligned at the center of the cell during

1. Metaphase

2. Anaphase

3. Prophase

4. Telophase

Q. The nerve cell of humans have 46 chromosomes. The chromosome number in the sperm of a male human will be __________. ​

1. 92
2. 46
3. 23

Q.

Define chiasma.

Q. What are chromosomes? Why are they called so?

Q. Difference between genome & chromosome

Q. The zygote undergoes meiotic division to form a ball of cells that gets implanted in the uterine wall.

1. True
2. False

Q.

How can sister chromatids be bi-oriented on the second meiotic spindle?

Q. Complete the paragraph by choosing the appropriate words given in the brackets: (3 marks)

(gamete, crossing over, haploid, Meiosis-II, meiosis-I, diploid)

……….. is just like mitosis. In this stage, the two haploid daughter cells formed in ……… undergo division by separation of recombined sister chromatids and four ……….. daughter cells are formed. Process of …………… production and spore formation occurs by meiosis. In this type of cell division, four haploid (n) daughter cells are formed from one ……….. cell. During this cell division, ………… occurs between, the homologous chromosomes.

Q. do chromosome also contain histone proteins or it is present in chromatin only ?

Q. At which stage are chromosomes best observed?

Q. A chromosome consists of _____ chromatid (s), _______ centromere(s).

1. 2, 2
2. 1, 2
3. 1, 1
4. 2, 1

Q. Cells divide by mitosis for growth and repair in an organism.

1. True
2. False

Q. Match the following.

1. Chromosome
2. Chromatin
3. DNA

Q. The chromosome number in Rattus rattus is

1. 40
2. 44
3. 38
4. 42

Q. Which of the following is not true about karyokinesis?

1. Karyokinesis starts with condensation of chromosomes.
2. Centrioles and spindle fibers help in karyokinesis.
3. It is the division of nucleus.
4. Cytoplasmic division is called karyokinesis.

Q. What is the non-functional part of the DNA called?

Q. Chromosomal material becomes untangled during the process of chromatin condensation
And what is meaning of untangled

Q. Burst the bubbles with the correct outcome of cell division.

1. Tumour
2. Growth
3. Nerve conduction
4. Repair
5. Fertilisation
6. Gaseous exchange
7. Replacement
8. Reproduction

Q. Cell division is the process by which a parent cell divides into two or more daughter cells.

1. False
2. True