Answer the following question. Explain the following parts of male reproductive system along with labelled diagram showing these parts- - Biology

Advertisements
Advertisements
Answer in Brief

Answer the following question.

Explain the following parts of male reproductive system along with labelled diagram showing these parts- Testis, vasa deferentia, epididymis, seminal vesicle, prostate gland and penis.

Advertisements

Solution

The male reproductive system consists of the following:
i. Primary sex organs (Gonads): Testes
ii. Accessory organs: Accessory ducts and accessory glands
iii. External genitalia: Scrotum and Penis

i. Primary sex organs: Testes

Testes are a pair of primary sex organs which are mesodermal in origin. They are located outside the abdomen in a pouch called scrotum, i.e. extra-abdominal in position. Testes develop in the abdominal cavity (early foetal life) and later descend into the scrotal sac through a passage called inguinal canal. They are suspended in the scrotal sac by the spermatic cord. Testes are connected to the wall of scrotum by a short fibromuscular band called gubernaculum.
They are oval in shape, about 4 to 5 cm long, 2 to 3 cm wide, and 3 cm thick.
The outermost covering of the testis is formed of a dense fibrous membrane called tunica albuginea.

ii. Accessory sex organs:

It includes accessory ducts, accessory glands.

a. Accessory ducts:

1. Rete testis:
The seminiferous tubules of the testis at the posterior surface form a network of tubules called rete testis. The rete testis opens into vasa efferentia. 2. Vasa efferentia:
Vasa efferentia are 12-20 fine tubules arising from the rete testis and join to the epididymis. They carry sperms from the testis and open into the epididymis.
3. Epididymis:
It is a long and highly coiled tube which is differentiated into an upper caput-, middle corpus- and lower cauda epididymis. The sperms undergo maturation in the epididymis.

4. Vasa deferens:
The vas deferens travels up to the abdominal cavity and loops over the ureter to open into the urethra. Vas deferens join the seminal vesicle to form ejaculatory duct.

5. Ejaculatory ducts:
The ejaculatory duct passes through the prostate gland and opens into the urethra.

6. Urethra:
The urethra provides a common passage for the urine and semen and hence is also called urinogenital duct. In males the urethra is long and extends through the penis. It opens to the outside by an opening called the urethral meatus or urethral orifice.

b. Accessory glands:

1. Seminal vesicles:
These are a pair of small fibromuscular pouches present on the posterior side of the urinary bladder. They secrete a seminal fluid (alkaline) containing citric acid, fructose, fibrinogen, and prostaglandins. About 60% of the total volume of semen is made up of seminal fluid. Fructose provides energy to sperms for swimming, while fibrinogen helps in coagulation of semen after ejaculation for quick propulsion into the vagina. The prostaglandins stimulate reverse peristalsis in vagina and uterus aiding the faster movement of sperms towards the egg in the female body.

2. Prostate gland:
Prostate gland consists of 20 to 30 lobes and is located under the urinary bladder. It surrounds the urethra. It releases a milky white, alkaline fluid called prostatic fluid into the urethra. Prostatic fluid forms about 30% of the total volume of semen. It contains citric acid, acid phosphatase and various other enzymes.
The acid phosphatase protects the sperm from the acidic environment of the vagina.

3. Cowper’s glands:
Cowper’s glands are also known as bulbourethral glands. These are pea-sized and lie on either side of membranous urethra. They secrete a viscous, alkaline, mucous like fluid which acts as a lubricant during copulation.
Semen: It is the viscous, alkaline and milky fluid (pH 7.2 to 7.7) ejaculated by the male reproductive system. Generally, 2.5 to 4.0 ml of semen is given out during a single ejaculation and it contains about 400 million sperms. Semen contains secretion of the epididymis and the accessory glands for nourishing (fructose), neutralizing acidity (Ca++, bicarbonates), activation for movement (prostaglandins).

iii. External genitalia:

a. Penis:
The penis is the male copulatory organ. It is cylindrical and muscular with three bundles of erectile tissue: a pair of postero-lateral tissue called corpora cavernosa and a median corpus spongiosum. The swollen tip of the penis is called glans penis. It is covered by a loose fold of skin called foreskin or prepuce.

b. Scrotum:
It is a loose pouch of pigmented skin lying behind the penis and is divided into a right and left scrotal sac by a septum of tunica dartos made of smooth muscle fibres. The foetal testes are guided into and retained in the scrotum by a short fibro muscular band called gubernaculum. The testes remain suspended in scrotum by a spermatic chord.
The failure of the testis to descend into the scrotum is called cryptorchidism which also results in sterility.
The cremaster and dartos muscles of scrotum help in drawing testes close or away from the body. This helps in maintaining the temperature of the testis 2-3 0C lower than the normal body temperature, necessary for spermatogenesis.

  Is there an error in this question or solution?
Chapter 2: Reproduction in Lower and Higher Animals - Exercises [Page 48]

APPEARS IN

Balbharati Biology 12th Standard HSC for Maharashtra State Board
Chapter 2 Reproduction in Lower and Higher Animals
Exercises | Q 6.1 | Page 48

RELATED QUESTIONS

Which mode of reproduction gives rise to variation?


Give the importance of variation in survival of species.


Complete the following table to get the differences between asexual and sexual reproduction:

Characteristics Asexual Reproduction Sexual Reproduction
Number of parents involved ........................... ..............................
Type of cells involved Somatic cells Germ cells
Type of cell division ............................ Meiosis and mitosis

What is meant by sexual reproduction?


Name two main processes of sexual reproduction


What are chromosomes?


What is amphimixis?


Describe the process of fertilization in human beings.


Choose the most appropriate answer.

Internal fertilization occurs


Choose the most appropriate answer.

The number of nuclei present in a zygote is


Indicate whether the following statements are True (T) or False (F).

Oviparous animals give birth to young ones. ( )


Indicate whether the following statement is True (T) or False (F).

Each sperm is a single cell. ( )


Indicate whether the following statement is True (T) or False (F).
A new human individual develops from a cell called gamete. ( )


Indicate whether the following statement is True (T) or False (F).

A zygote is formed as a result of fertilization. ( )


Give two differences between a zygote and a foetus.


Differentiate between internal fertilization and external fertilization.


Complete the crossword puzzle using the hints given below.

Across

1. The process of the fusion of the gametes.

6. The type of fertilization in hen.

7. The term used for bulges observed on the sides of the body of Hydra.

8. Eggs are produced here

Down

2. Sperms are produced in these male reproductive organs.

3. Another term for the fertilized egg.

4. These animals lay eggs.

5. A type of fission in amoeba.


Which species is likely to have better chances of survival - the one reproducing asexually or the one reproducing sexually? Justify your answer.


Name two animals which reproduce sexually.


What is the name of sex cells (other than gametes)?


name the organ which produces male sex cells.


Fill in the following blank with suitable word :

The cells involved in sexual reproduction are called .............


In which sort of reproduction are gametes involved?


 Write the various steps involved in the sexual reproduction in plants.


 Name two plants which reproduce by sexual reproduction method and two plants which reproduce by asexual reproduction methods.


Distinguish between the following pair of terms:

Sexual reproduction and asexual reproduction.


What is the function of uterus?


Multiple choice question. Tick (✓) the correct choice:

Butterfly in its development from larva to an adult shows

  1. multiplication
  2. metamorphosis
  3. fertilisation
  4. none of the above

Differentiate between the following:

Sperm and Ovum


Differentiate between the following:

External fertilisation and Internal fertilisation.


Mention the common method of reproduction in Hydra.


Mention the common method of reproduction in Start fish.


Name the organ involved in the following:

Fertilisation of ovum by tile sperm.


Describe the different methods of asexual reproduction in animals.


Adolesecence is considered a critical stage in the life of boys and girls. Explain this statement.


Describe the various stages in the life cycle of a butterfly.


“The chromosomes number of the sexually reproducing parents and their offspring is the same.” Justify this statement. 


Sketch and label the diagram showing self- and cross-pollination.


In the sexual mode of reproduction, greater diversities are generated.


Answer in one sentence.

Outline the path of sperm upto the urethra.


Answer in one sentence.

Which glands contribute fluids to the semen?


Answer in one sentence.

Name the endocrine glands involved in maintaining the sex characteristics of males.


Answer the following question.

Explain the histological structure of ovary in human.


Answer the following question.

Which is the function of male accessory glands?


Long answer question.

Describe female reproductive system of human.


What is atresia with respect to ovary in human females?


Identify the labels from the given diagram.


Write an account of the seminal vesicle and bulbourethral gland in the male reproductive system.


Which are the components of pollination?


Animals which give birth to young ones directly are named as ______.


What are the different stages of sexual reproduction?


Which organs/glands produce eggs and sperms?


In an ovule, meiosis occurs in ______


Due to presence of which of the following chemical component, pollen grains can remain well preserved in fossil?


Testosterone is produced by ____________.


Which of the following is the male accessory gland?


Identify the INCORRECT statement.


Match column -1 with column - II and select the correct option.

  Column - I   Column - II
1. Seminal vesicles a. Membranous urethra
2. Scrotum b. Thermoregulatory
3. Tunica vaginalis c. Fibro muscular pouches
4. Cowper's gland d. Peritoneal covering

______ is the first stage of sexual reproduction.


______ fertilisation takes place in frogs and fish.


The zygote divides repeatedly into a group of cells, which develops into different tissues and organs constituting a full body. This structure is known as ______.


Animals in which an embryo develops outside the body are called ______ animals.


Name the two ways by which fertilisation in animals takes place.


What is external fertilisation?


Explain the two types of fertilization.


Explain the formation of the embryo.


Which is a better mode of reproduction, sexual or asexual? Why?


Share
Notifications



      Forgot password?
Use app×