In a flower, the parts that produce male and female gametes (germ cells) are:
stamen and anther
filament and stigma
anther and ovary
stamen and style
(3)
In a flower, the parts that produce male and female gametes are anther and ovary respectively. Stamen is the male reproductive unit of the flower. It contains a bilobed anther at the top which produces male gametes. Filament is the stalk of the stamen that supports anther.
Pistil (carpel) is the female reproductive part of the flower. It consists of ovary (forms ovules-female gametes), stigma (receives pollen) and style (elongated tube).
Which of the following is the correct sequence of events of sexual reproduction in a flower?
Pollination, fertilisation, seedling, embryo
Seedling, embryo, fertilisation, pollination
Pollination, fertilisation, embryo, seedling
Embryo, seedling, pollination, fertilisation
(3)
The correct sequence of events are:
Pollination (transfer of pollen from stamen to stigma)
Fertilisation (fusion of germ cells to form zygote)
Embryo formation (zygote divides several times to form an embryo within the ovule)
Seedling (ovule develops a tough coat and converts into a seed)
Which of the following statements are true for flowers?
(i) Flowers are always bisexual.
(ii) They are the sexual reproductive organs.
(iii) They are produced in all groups of plants.
(iv) After fertilisation they give rise to fruits.
(i) and (iv)
(ii) and (iii)
(i) and (iii)
(ii) and (iv)
(4)
Flowers are the sexual reproductive organs of a plant. They are produced in angiosperms. Majority of flowers are bisexual. After fertilisation, they give rise to fruits.
Which among the following statements are true for unisexual flowers?
(i) They possess both stamen and pistil.
(ii) They possess either stamen or pistil.
(iii) They exhibit cross pollination.
(iv) Unisexual flowers possessing only stamens cannot produce fruits.
(i) and (iv)
(ii), (iii) and (iv)
(iii) and (iv)
(i), (iii) and (iv)
(2)
The flowers which are unisexual (papaya, watermelon) contain either stamens or carpels. Since only one reproductive organ is present in them, they depend on cross pollination to form zygote after fertilisation. Both stamen and carpels are required for fertilisation, so only one of them cannot produce fruits.
Which among the following statements are true for sexual reproduction in flowering plants?
(i) It requires two types of gametes.
(ii) Fertilisation is a compulsory event.
(iii) It always results in formation event.
(iv) Offspring formed are clones.
(i) and (iv)
(i), (ii) and (iv)
(i), (ii) and (iii)
(i), (ii) and (iv)
(3)
Sexual reproduction creates variation in organisms. So, clones cannot be produced through it. Clones are identical copies of parent organism. Sexual reproduction needs two type of gametes, i.e., male and female to form zygote after fertilisation.
In figure, the parts A, B and C are sequentially
cotyledon, plumule and radicle
plumule, radicle and cotyledon
plumule, cotyledon and radicle
radicle, cotyledon and plumule
(3)
Plumule ‘A’ grows into shoots, cotyledon ‘B’ stores food and radicle ‘C’ grows into roots.
The figure is given alongside shows the human male reproductive organs. Which structures make sperms and seminal fluid
V makes sperms and X makes seminal fluid
W makes sperms and Y makes seminal fluid
X makes sperms and W makes seminal fluid
Y makes sperms and W makes seminal fluid
(4)
Y represents the testes that produce sperms and W represents the Seminal vesicle that produces seminal fluid.
The male human reproductive system consists of the testes and the male accessory glands. Which of the following statements about male accessory glands is false?
The prostate gland also synthesises sperm.
The prostate gland and seminal vesicles are found outside the testes.
The secretions of prostate gland and seminal vesicles make semen fluid and provide nutrition.
Male accessory glands contribute to semen.
(1)
Sperm is synthesized only by the testes. The prostate gland and seminal vesicles are found outside the testes along the path of vas deferens. Secretions from the prostate gland and seminal vesicle glands contribute to the composition of semen. The seminal vesicles secretions include fructose and nourishment for sperm cells. Secretions from the prostate gland contribute to the fluid in semen.
In human males, the testes lie in the scrotum, because it helps in the:
process of mating
formation of sperm
easy transfer of gametes
all of the above
(2)
Formation of germ cells or sperms takes place in the testes and it lies in the scrotum. In the scrotum (outside the abdominal cavity), the temperature is about 3°C lower than the temperature of the body. Testes lie in scrotum because the sperm formation requires a lower temperature than the normal body temperature.
Which among the following is not function of testes at puberty?
(i) Formation of germ cells
(ii) Secretion of testosterone
(iii) Development of placenta
(iv) Secretion of estrogen
(i) and (ii)
(ii) and (iii)
(iii) and (iv)
(i) and (iv)
(3)
Development of placenta and secretion of estrogen are related to female reproductive system, hence are not the function of testes at puberty.
