17 - Chromosome and Sex Determination

In this post, you can check the solutions to the exercises of Chromosome and Sex Determination of Oasis School Science Grade 10 by Jayananda Kapadi.

Group A

1. What is a chromosome?
Answer: A chromosome is a microscopic substances that is contained in the nucleus of a cell and acts as a vehicles of heredity.

2. Where is chromosome found?
Answer: Chromosome is found in the nucleus of a cell.

3. What is chromosome made up of?
Answer; Chromosome is made up of proteins and DNA.

4. What is gene?
Answer: Gene is a tiny unit of heredity that transmits the parental characteristics to their offsprings.


5. What is gene made up of?
Answer: Genes are made up of histone protein and DNA.

6. What is chromatic reticulum?
Answer; The chromatin fibres in the nucleus of a growing cell form a network type structure that is called chromatic reticulum. [Source: Biologydiscussion]

7. Define centromere and chromatid.
Answer: Centromere is the point where two chromatids are tied together. Chromatid is a thread-like structure present in the chromosome.

8. What is kinetochore?
Answer: Centromere can also be referred to as kinetochore.

9. How many types of chromosomes are there on the basis of position of centromere?
Answer: On the basis of position of centromere, there are four types of chromosomes.

10. Define sub-metacentric chromosome.
Answer: A chromosome whose centromere is place around the centre but not exactly at the centre is defined as sub-metacentric chromosome.

11. What is telocentric chromosome?
Answer: Telocentric chromosome is a type of chromosome in which the centromere lies to the pole of the chromosome.

12, 13, 14. Write down the number of chromosomes found in somatic cell and gametic cell of given organisms:
  • Name of Organism | Somatic Cells | Gametic Cells
  • i) Housefly | 12 | 6
  • ii) Gorilla | 48 | 24
  • iii) Solanum | 16 | 8
  • iv) Onion | 16 | 8
  • v) Pine | 24 | 12
  • vi) Yeast | 2 | 1


15. What is sex determination?
Answer: Sex determination is the process of determining the sex of a human being as boy or girl by the composition of chromosomes in their cells.

16. What is haemophilia?
Answer: Haemophilia is a sex-linked disease occurring in male in which their is slow clotting of blood.

18. Write any two characteristics of haemophilia.
Answer: Any two characteristics of haemophilia are:
  • It is a sex-linked disease.
  • It creates slow clotting of blood.
19. Write any two characteristics of chromosome.
Answer: Any two characteristics of chromosome are:
  • It always remains constant in a particular species, in general condition.
  • It acts as the vehicle of heredity.
20. What is Down's syndrome?
Answer: Down's syndrome is a diseased condition of human body in which there is an extra copy of Chromosome 21, also known as the trisomy of chromosome 21.

21. Write down the main cause of Down's syndrome.
Answer: The main cause of Down's syndrome is the trisomy of Chromosome 21.

22. What is Klinefelter's syndrome?
Answer: Klinefelter's syndrome is a chromosomal disorder in which there are 47 chromosomes (XXY) in a male body.

23. What is Turner's syndrome?
Answer: Turner's syndrome is a diseased condition of human body caused due to the absence of X chromosome in females.


Group B


About this book:

Oasis School Science Grade 10
Author: Jayananda Kapadi
Editor: Dr. Rameshwar Adhikari

About Oasis Publication:

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