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Spermatogenesis

Scrotum testes are present in man.

Fertilization occurs in the female reproductive system is Oviduct.

(d) Epididymis → vas deferens → urethra

External fertilization: It occurs outside the body of the animal through a medium such as water.

Internal fertilization: It occurs inside the body of the female.

In a boy: Change of voice and discharge of semen.

In a girl: Appearance of the menses, appearance of mammary glands and widening of the hips.

Testosterone is the male reproductive hormone produced by the interstitial cells or the Leydig cells. These cells are located in the testes. They serve as a packing tissue between the coils of the seminiferous tubules. Therefore, it can be said that the testes produce the male hormone testosterone.

The union of male and female gametes to form the zygote is called fertilization. In human female the site of fertilization is oviduct or fallopian tube.

(a) Scrotum

(b) Seminiferous Tubules

(c) Graafian Follicle

(d) Seminal vesicle

(e) Epididymis

(a) Transforming Principle 

▪ Frederick Griffith (1928) conducted experiments with Streptococcus pneumoniae (bacterium causing pneumonia). 

▪ He observed two strains of this bacterium—one forming smooth shiny colonies (S-type) with capsule, while other forming rough colonies (R-type) without capsule. 

▪ When live S-type cells were injected into mice, they died due to pneumonia. 

▪ When live R-type cells were injected into mice, they survived. 

▪ When heat-killed S-type cells were injected into mice, they survived and there were no symptoms of pnuemonia. 

▪ When heat-killed S-type cells were mixed with live R-type cells and injected into mice, they died due to unexpected symptoms of pneumonia and live S-type cells were obtained from mice. 

▪ He concluded that heat-killed S-type bacteria caused a transformation of the Rtype bacteria into S-type bacteria but he was not able to understand the cause of this bacterial transformation. 

(b) Oswald Avery, Colin MacLeod and Maclyn McCarty. 

(c) Biochemical Characterisation of Transforming Principle 

▪ Oswald Avery, Colin MacLeod and Maclyn McCarty repeated Griffith’s experiment in an in vitro system in order to determine biochemical nature of transforming principle. 

▪ They reported that DNA from the heat-killed S-type bacteria caused the transformation of nonvirulent R-type bacteria into virulent S-type bacteria. 

▪ They also discovered that proteases and RNases did not affect transformation while DNases inhibited the process. 

▪ They concluded that DNA is the hereditary material.

Correct option is D) All the above

Flowers which contain either only pistil or only stamens are called unisexual flowers. 

Eg : corn, papaya, cucumber Flowers which contain both stamens and pistil are called bisexual flowers. 

Eg : Rose, mustard, petunia

The correct option is B) Bisexual flower.

(a) Testosterone

(b) Ureter

(c) Ovum

(d) After birth

Semen is a fluid which contains sperm cells, secretion of accessory glands, fibrinogen, thromboplastin and calcium salts.

In some flowers either androecium or gynoecium is present. Such type of flowers are called unisexual flowers.

Seminiferous tubule → Epididymis → Vas deferens → Penis

a) The flowers in pumpkin are unisexual. This statement is true. 

b) Seeds are formed in asexual reproduction. This statement is false. Seeds are formed in sexual reproduction. 

c) Generally, roses are propagated through seeds. This statement also false. Generally, rose plants are propagated through a vegetative propagation method called stem cuttings.

(a) Testes → Sperms → Sperm duct → Semen → Penis

(b) Menarche → Puberty → Reproductive age → Menstruals→ Menopause

(c) Graafian follicle → Ostium → Fallopian tube Uterus

Unisexual flowers are found in

1. mulberry

(a) Ovulation → fertilization → implantation → gestation child birth

(b) Sperm → sperm duct → urethra → coitus → vagina → ovum

Pollen grain is the odd-one out as it is part of the stamen (male reproductive part) while the rest three are parts of a carpel (female reproductive part of the flower).

(i) Vas Deferens: It helps in the passage of sperms.

(ii) Testes: It produces sperms and male sex hormone testosterone.

(iii) Prostate gland: It secretes alkaline fluid which is discharged into the urethra. It protects sperms from the acidity of the male urethra.

3. artificial pollination

The embryo gets nutrition from the mother's blood with the help of a special tissue called placenta.

This is a disc which is embedded in the uterine wall and transfer glucose and oxygen from the mother to the embryo.

Embryo is present in the womb of a mother where it is connected with the uterine wall of mother by placenta. The fetus receives oxygen, nourishment and other life supporting things from mother through this placenta.

Insects, birds, animals, air and water are the pollinating agents.

Ovule is the odd-one out as it is a part of female reproductive organ (carpel) of a flower while the rest three are parts of male reproductive organ (stamen) of the flower.

Gamete is the odd-one out as it is responsible for sexual reproduction while rest three are methods of asexual reproduction.

(a) Male.

(b) Female.

(c) Fruit.

(d) Seed.

(e) Sexual.

(f) Carpel.

(g) Stamen.

(h) Anther.

(i) Ovary.

(j) Cross pollination.

(k) Gametes.

(l) Zygote.

(m) Fertilisation.

(n) Single cell (zygote).

(o) Fertilisation; fertilised.

(p) Hormones.

The embryo gets nourishment from the mother's blood with the help of a special tissue called the placenta. This is a disc which is embedded in the uterine wall. It contains villi on the embryo's side of the tissue. On the mother's side are the blood spaces. which surround the villi. This provides a large surface area for glucose and oxygen to pass from the mother to the embryo.

1. Gamete: Gamete is a male or female reproductive cell that unites with another gamete during sexual reproduction to form zygote. 

2. Pollination: Pollination is the transfer of pollen grains from the ripe anther to the stigma of a flower in same plant or another plant. 

3. Zygote: Zygote is a product formed by the fusion of the male and female gametes.

(d) pollen grains.

Pollen is produced in the:

4. Anther

The correct option is D) Pollengrain.

Air, water, animals, insects, humans act as agents of pollination.

a) Potato: 

1. It has a number of small depressions on its surface. These are known as eyes. 

2. Potato plants sprout through these eyes. 

b) Bryophyllum: 

1) on the edge of the leaves of Bryophyllum, the plant Bryophyllum reproduces.

The correct option is B) Pistil.

Correct option is A) Stamen

The correct option is A) Stamen.

Self pollination: 

In self pollination pollen grains of the same flower reaches the stigma. No Agency is required. . 

Cross pollination: 

In cross pollination, the pollen grains of another flower either on same or other plant reaches the stigma. Agencies are required.

Correct option is (iv) flower

Asexual reproduction:

(a) Only one parent plant is involved.
(b) Occurs in unisexual plants.
(c) Occurs in lower plants.
(d) Reproductive organs are notpresent.
(e) In most of the methods the original parent disappears.
(f) A process like a gamete formation or fertilization is not seen.
(g) Characteristics of only one parent are inherited.
(h) No need for seeds.

Sexual reproduction:

(a) Both male and female parents are involved.
(b) Occurs in bisexual plants.
(c) Occurs in higher plants.
(d) Fully developed reproductive parts are present.
(e) Original parents remain alive after the process of reproduction.
(f) Fertilization of gametes gives rises to zygote.
(g) Characteristics of both parents are inherited.
(h) Seeds are used to get new plants from a flower.

(a) A is correct R is incorrect.

Correct option is  D) 5

Correct option is A) 5