Short Answer TypeHow is 'oogenesis' markedly different from 'spermatogenesis' with respect to the growth till puberty in the humans?
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Spermatogenesis |
Oogenesis |
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It is the process by which sperms are formed from the sperm mother cell in males. |
It is the process by which ovum is formed from the oogonia in females. |
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After the second meiotic divisions in a single spermatogonium, 4 spermatids are obtained, which undergo maturation to form 4 sperm cells, or spermatozoa |
After the second meiotic divisions in the single oogonium, only one ovum and three polar bodies are obtained. |
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Spermatogenesis occurs in males from puberty to death. |
In females, oogenesis starts before birth and occurs until menopause. |
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 TypeLong 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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