(i). How does an egg from the ovary reach uterus and develops into foetus?
(ii) What are the changes that occur in the uterus for the development of th
foetus?
Or
in sexual reproduction,
(i) how does the re-establishment of DNA amount occur in the new generation
(ii) how is the amount of variations increase among the individuals of each
the population?
Answers
Answer:
(I)A pregnancy starts with fertilization, when a woman's egg joins with a man's sperm. Fertilization usually takes place in a fallopian tube that links an ovary to the uterus. If the fertilized egg successfully travels down the fallopian tube and implants in the uterus, an embryo starts growing.
(ii)During pregnancy, the lining of your uterus thickens and its blood vessels enlarge to provide nourishment to the fetus. As pregnancy progresses, your uterus expands to make room for the fetus. By the time your baby is born, your uterus will have expanded to many times its normal size.
Answer:
(I) A pregnancy starts with fertilization, when a woman's egg joins with a man's sperm. Fertilization usually takes place in a fallopian tube that links an ovary to the uterus. If the fertilized egg successfully travels down the fallopian tube and implants in the uterus, an embryo starts growing.
(ii) During pregnancy, the lining of your uterus thickens and its blood vessels enlarge to provide nourishment to the fetus. As pregnancy progresses, your uterus expands to make room for the fetus. By the time your baby is born, your uterus will have expanded to many times its normal size.