biology 12th cbse

 one mark question

question 1

Ovulation in the human female normally takes place during the menstrual cycle

ans:at the end of the proliferative phase

question 2

After ovulation Graafian follicle regresses into

ans: corpus luteum

question 3

Immediately after ovulation, the mammalian egg is covered by a membrane known as

ans:Corona radiata

question 4

Which one of the following events is correctly matched with the time period in a normal

ans: Endometrium regenerates : 5 – 10 days

question 5

If mammalian ovum fails to get fertilised, which one of the following is unlikely

ans: Estrogen secretion increases.

question 6

human female reaches menopause aroung the age of

ans:50 years

question 7

reaction of granules content which harden the zona pellucida and ensures sure block to polyspermy is

ans:Cortical reaction

question 8

Which part of the sperm plays an important role in penetrating the egg membrane ?

ans:Acrosome

question 9

In oocyte secondary maturation occurs in

ans:Fallopian tube

question 10

Which of the following hormones is not secreted by human placenta ?

ans: LH

question 11

Morula is a developmental stage

ans:between the zygote and blastocyst

question 12

Temperature of the scrotum which is necessary for the functioning of testis is always ________ around below body temperature.

ans:  2.c

question 13

 The nutritive cells found in seminiferous tubules are

ans: Sertoli cells

 

question 14

Which part of ovary in mammals acts as an endocrine gland after ovulation ?

ans: Germinal epithelium

question 15

1st polar body is formed at which stage of oogenesis ?

ans: First miosis