Short Answer TypeHow is 'oogenesis' markedly different from 'spermatogenesis' with respect to the growth till puberty in the humans?
Draw a sectional view of human ovary and label the different follicular stages, ovum and Corpus luteum.
Mention any three characteristics of Neanderthal man that lived in near east and central Asia.
Long Answer Type(a) Name the technology that has helped scientists to propagate on a large scale the desired crops in a short duration. List the steps carried out to propagate the crops by the said technique.
(b) How are somatic hybrids obtained?
Short Answer TypeDescribe the process of Parturition in humans.
Parturition is the process of childbirth or the delivery of the foetus because of vigorous contraction of uterus at the end of the pregnancy which is after the 9 month gestation period. It is induced by a complex neuroendocrine mechanism. Fully developed foetus gives the signal which induces mild uterine contraction called foetal ejection reflex. This triggers results in release of oxytocin from maternal pituitary. The oxytocin results in stronger contractions of the uterine walls and the secretion of more and more oxytocin. The effect of oxytocin and uterine wall contraction leads to stronger contraction which leads to the expulsion of the foetus through the birth canal or parturition.
Long Answer TypeDuring the reproductive cycle of a human female, when, where and how does a placenta develop? What is the function of placenta during pregnancy and embryo development?
Short Answer TypeDraw a diagram of the microscopic structure of human sperm. Label the following parts in it and write their functions.
(a) Acrosome
(b) Nucleus
(c) Middle piece
Long Answer Type(a) Draw a diagrammatic sectional view of the female reproductive system of human and label the parts:
(i) where the secondary oocytes develop
(ii) which helps in collection of ovum after ovulation
(iii) where fertilization occurs
(iv) where implantation of embryo occurs.
(b) Explain the role of pituitary and the ovarian hormones in menstrual cycle in human females.Short Answer Type
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