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प्रश्न
The diagram given below is that of a developing human foetus. Study the diagram and then answer the questions that follow:
(i) Label the parts numbered 1 to 3 in the diagram.
(ii) Mention any two functions of the part labelled 2 in the diagram.
(iii) Explain the significance of the part numbered 3 in the diagram.
(iv) Define the term ‘Gestation’. What is the normal gestational period of the developing human embryo?
(v) Mention the sex chromosomes in a male and female embryo.
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उत्तर
(i)
- Umbilical cord
- Placenta
- Amniotic fluid
(ii) Functions of placenta:
- It allows the diffusion of oxygen, nutrients and immune products from the mother to the foetus.
- It allows the diffusion of waste material generated by the foetus to the mother to be excreted.
(iii)
- The amniotic fluid prevents the foetus from injury and shocks.
- It allows the foetus some amount of movement.
- It prevents the amnion from sticking to the foetus.
- It maintains an even pressure all around the foetus.
(iv) The time period required for the development of the foetus inside the uterus is called gestation. The normal gestation period in humans is 280 days (9 months).
(v) Male sex chromosomes: One ‘X’ chromosome and one ‘Y’ chromosome (XY) Female sex chromosomes: Two ‘X’ chromosomes (XX)
APPEARS IN
संबंधित प्रश्न
What are the functions of testes in the human male reproductive system?
Describe in brief what happens to the zygote after it gets implanted.
Give scientific reasons: When an ovum gets fertilized, menstrual cycle stops temporarily in a woman.
Where is the male gamete formed in humans?
What name is given to the fusion of sperm and ovum?
The germ cell A produced by a person X is round in shape and it fuses with another germ cell B having a long tail and produced by a person Y. The fusion of A and B produces a new cell C. The cell C divides repeatedly and grows inside the organ D of person X to form E in which the body features of the unborn baby are not much developed. E grows further to form F in which the various body features of the unborn baby (like hands, legs, head, eyes, and ears, etc.) can be identified. F grows further and ultimately forms a baby. What are A, B, C, D, E and F? Out of the two persons X and Y, which one is male and which one female?
Label the folowing diagram
Choose the Odd One Out:
Choose the Odd One Out:
Multiple Choice Question:
What will happen if the temperature of the scrotal sacs temporarily goes to about 2°C lower than body temperature?
