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प्रश्न
The below diagram is of a developing embryo is a mother’s womb:
(i) Write the functions of the placenta, amnion, and umbilical cord.
(ii) How are the waste products of a fetus removed?
(iii) What is the gestation period?
उत्तर
(i) Functions:
1. It supplies oxygen, water, nutrients and hormones from the mother to embryo.
2. It transfers. carbon dioxide and other waste materials from the embryo to the mother’s blood.
3. It shields the embryo from infections as it is impermeable to most of the microorganisms present in the mother’s blood.
4. It produces certain hormones like oestrogen and progesterone which are essential for the reproductive process.
The amnion or amniotic sac is made up of protective membranes that are formed around the embryo. It encloses a fluid-filled space which acts as a water-bath and excellent shock absorption for the young embryo.
5. The embryo that develops in the placenta is maintained at a constant temperature, is well protected and nourished by the umbilical cord.
(ii) Waste products of the fetus are removed through the umbilical cord.
(iii) The interval of time between fertilization and birth is called the gestation period. It is about 280 days in human beings.
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संबंधित प्रश्न
Name any three parts of the female reproductive system in human beings. Write one function of each.
Describe in brief the structure of placenta
What are the organs in humans which produce the gametes?
Draw a labelled diagram of the human female reproductive system. With the help of this diagram, explain the working of human female reproductive system.
What is ovulation? How often does it happen in human females?
Diagram shows the reproductive system of female human beings:
(i) Name the parts numbered 1 to 14.
(ii) Normally, after how many days does an ovary release an egg?
(iii) Where are the sperms released during coitus?
(iv) What is the role of sperms after their ejaculation in vagina?
(v) What is the function of the organ numbered 5?
(vi) What is the gestation period in human?
Choose the correct answer:
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Define the following:
Parthenogenesis
Answer the following question.
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