Question

Give any four significances of fertilization in human.

Hint:

The three germ layers – ectoderm, mesoderm, and endoderm – give rise to all the organs and tissues in the body during development.

Answer 1

Step 1: Understanding Fertilization.
Fertilization is the process in which the male sperm fuses with the female ovum to form a zygote. This is a crucial step in human reproduction.
Step 2: Significances of Fertilization.
1. Restoration of Chromosome Number: Fertilization restores the diploid number of chromosomes by combining the haploid sets from the sperm and egg.
2. Genetic Variation: Fertilization introduces genetic diversity by combining genetic material from both parents.
3. Development of Zygote: The fertilized egg (zygote) starts to divide and differentiate, leading to the development of a new individual.
4. Sex Determination: The fertilization of an egg by a sperm carrying either an X or Y chromosome determines the sex of the offspring.
Step 3: Conclusion.
Fertilization is essential for genetic diversity, development, and the restoration of the chromosome number in humans.
ii. Mention the names of any two organs each derived from ectoderm and mesoderm.
Solution:
Step 1: Understanding Germ Layers.
The ectoderm, mesoderm, and endoderm are the three primary germ layers formed during embryonic development. Different organs are derived from each of these layers.
Step 2: Organs Derived from Ectoderm and Mesoderm.
- Ectoderm-derived organs: 1. Skin 2. Nervous system (brain and spinal cord)
- Mesoderm-derived organs: 1. Muscles 2. Kidneys
Step 3: Conclusion.
The ectoderm gives rise to the skin and nervous system, while the mesoderm forms the muscles and kidneys.