Human Reproduction

Which one of the following statements about human sperm is correct?

1. Acrosome has a conical pointed structure used for piercing and penetrating the egg, resulting in fertilisation
2. The sperm lysins in the acrosome dissolve the egg envelope facilitating fertilisation
3. Acrosome serves as a sensory structure leading the sperm towards the ovum
4. Acrosome serves no particular function

Which one of the following statements about morula in humans is correct?

1. It has almost equal quantity of cytoplasm as an uncleaved zygote but much more DNA
2. It has far less cytoplasm as well as less DNA than in an uncleaved zygote
3. It has more or less equal quantity of cytoplasm and DNA as in uncleaved zygote
4. It has more cytoplasm and more DNA than an uncleaved zygote

The part of Fallopian tube closest to the ovary is

1. Isthmus
2. Infundibulum
3. Cervix
4. Ampulla

Seminal plasma in humans is rich in :

1. Fructose, calcium and certain enzymes
2. Fructose and certain enzymes but poor calcium
3. Glucose and certain enzymes but has no calcium
4. Fructose and calcium but has no enzyme

Which one of the following is the correct matching of the events occurring during menstrual cycle?

1. Ovulation: LH and FSH attain peak level and sharp fall in the secretion of progesterone
2. Menstruation: Breakdown of myometrium and ovum not fertilised
3. Secretory phase: Development of corpus luteum and increased secretion of progesterone
4. Proliferative phase: Rapid regeneration of myometrium and maturation of Graafian follicle

Given below is a diagrammatic sketch for a portion of human male reproductive system. Select the correct set of the names of the parts labelled A, B, C, D. [Figure]

1. A - Ureter, B - Seminal vesicle, C - Prostate, D - Bulbourethral gland
2. A - Vas deferens, B - Seminal vesicle, C - Prostate, D - Bulbourethral gland
3. A - Vas deferens, B - Seminal vesicle, C - Bulbourethral gland, D - Prostate
4. A - Ureter, B - Prostate, C - Seminal vesicle, D - Bulbourethral gland

Foetal ejection reflex in human female is induced by

1. Pressure exerted by amniotic fluid
2. Differentiation of mammary glands
3. Release of oxytocin from pituitary
4. Fully developed foetus and placenta

The correct sequence of spermatogenetic stages leading to the formation of sperms in a mature human testis is:

1. spermatocyte - spermatogonia - spermatid - sperms
2. spermatogonia - spermatid - spermatocyte - sperms
3. spermatid - spermatocyte - spermatogonia - sperms
4. spermatogonia - spermatocyte - spermatid - sperms

Which one of the following is the most likely root cause why menstruation is not taking place in regularly cycling human female?

1. Retention of well-developed corpus luteum
2. Maintenance of high concentration of sex hormones in the blood stream
3. Maintenance of the hypertrophical endometrial lining
4. Fertilisation of the ovum

A change in the amount of yolk and its distribution in the egg will affect:

1. Fertilisation
2. Pattern of cleavage
3. Formation of zygote
4. Number of blastomeres produced