NCERT Exemplar solutions for Biology [English] Class 12 chapter 3 - Human Reproduction [Latest edition]

Choose the incorrect statement from the following.

Identify the correct statement from the following:

Spot the odd one out from the following structures with reference to the male reproductive system.

Seminal plasma, the fluid part of semen, is contributed by.

1. Seminal vesicle
2. Prostate
3. Urethra
4. Bulbourethral gland

Spermiation is the process of the release of sperms from ______.

Mature Graafian follicle is generally present in the ovary of a healthy human female around stet ______.

Acrosomal reaction of the sperm occurs due to ______.

Which one of the following is not a male accessory gland?

The spermatogonia undergo division to produce sperms by the process of spermatogenesis. Choose the correct one with reference to above.

Match between the following representing parts of the sperm and their functions and choose the correct option.

Which among the following has 23 chromosomes?

Match the following and choose the correct options:

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

The vas deferens receives duct from the seminal vesicle and opens into urethra as ______.

Urethral meatus refers to the ______.

Morula is a developmental stage ______.

The membranous cover of the ovum at ovulation is ______.

Identify the odd one from the following.

Given below are the events in human reproduction. Write them in correct sequential order.

Insemination, gametogenesis, fertilisation, parturition, gestation, implantation

The path of sperm transport is given below. Provide the missing steps in blank boxes.

What is the role of cervix in the human female reproductive system?

Why are menstrual cycles absent during pregnancy?

Female reproductive organs and associated functions are given below in column A and B. Fill the blank boxes.

From where the parturition signals arise-mother or foetus? Mention the main hormone involved in parturition.

What is the significance of epididymis in male fertility?

Give the names and functions of the hormones involved in the process of spermatogenesis. Write the names of the endocrine glands from where they are released.

The mother germ cells are transformed into a mature follicle through series of steps. Provide the missing steps in the blank boxes.

During reproduction, the chromosome number (2n) reduces to half (n) in the gametes and again the original number (2n) is restored in the offspring, What are the processes through which these events take place?

What is the difference between a primary oocyte and a secondary oocyte?

What is the significance of ampullary–isthmic junction in the female reproductive tract?

How does zona pellucida of ovum help in preventing polyspermy?

Mention the importance of LH surge during menstrual cycle.

Which type of cell division forms spermatids from the secondary spermatocytes?

A human female experiences two major changes, menarche and menopause during her life. Mention the significance of both the events.

How many spermatozoa are formed from one secondary spermatocyte?

Where does the first cleavage division of zygote take place?

Corpus luteum in pregnancy has a long life. However, if fertilisation does not take place, it remains active only for 10 - 12 days. Explain.

What is foetal ejection reflex? Explain how it leads to parturition?

Except endocrine function, what are the other functions of placenta.

Why doctors recommend breast feeding during initial period of infant growth?

What are the events taking place in the ovary and uterus during follicular phase of the menstrual cycle.

Given below is a flow chart showing ovarian changes during menstrual cycle. Fill in the spaces giving the name of the hormones responsible for the events shown.

Give a schematic labelled diagram to represent oögenesis (without descriptions)

What are the changes in the oogonia during the transition of a primary follicle to Graafian follicle?

What role does pituitary gonadotropins play during follicular and ovulatory phases of menstrual cycle? Explain the shifts in steroidal secretions.

Meiotic division during oogenesis is different from that in spermatogenesis. Explain how and why?

The zygote passes through several developmental stages till implantation, Describe each stage briefly with suitable diagrams.

Draw a neat diagram of the female reproductive system and label the parts associated with the following:

(a) production of gamete

(b) site of fertilisation

(c) site of implantation

(d) birth canal

With a suitable diagram, describe the organisation of mammary gland.