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In a bisexual flower in spite of the young stamens being removed artificially, the flower produces fruit. Provide a suitable explanation for the above situation.

a) Stamens removed, but pistil is intact. When stamens of a bisexual flower are removed. Cross pollination can take place which results in... View Article

Which among the following diseases is not sexually transmitted? (a) Syphillis (b) Hepatitis (c) HIV – AIDS (d) Gonorrhoea

(b) Hepatitis Syphillis caused by Teponema pallidum and Gonorrhoea caused by Neisseria gonorrhoeae are sexually transmitted bacterial diseases.... View Article

The correct sequence of organs in the male reproductive system for transport of sperms is (a) testis → vasdeferens → urethra (b) testis → ureter → urethra (c) testis → urethra → ureter (d) testis → vasdeferens → ureter

testis → ;vasdeferens → urethra The sperms are produced in the Testis, stored in the epididymis and transported to the urethra... View Article

Which among the following is not the function of testes at puberty? (i) formation of germ cells (ii) secretion of testosterone (iii) development of placenta (iv) secretion of estrogen (a) (i) and (ii) (b) (ii) and (iii) (c) (iii) and (iv) (d) (i) and (iv)

C) (iii) and (iv) A pair of oval-shaped organs masked in a pouch called the scrotum. They are responsible for the production of sperms and the... View Article

In human males, the testes lie in the scrotum, because it helps in the (a) process of mating (b) formation of sperm (c) easy transfer of gametes (d) all the above

(b) formation of sperm Testes produce sperms. Sperms contain a haploid set of chromosomes of the father Testes produce a hormone known as... View Article

In human females, an event that reflects the onset of the reproductive phase is (a) growth of body (b) changes in hair pattern (c) change in voice (d) menstruation

d) Menstruation Human female reproductive development sequence: Thelarche (Breast development), Pubarche (pubic hair development) and Menarche... View Article

During adolescence, several changes occur in the human body. Mark one change associated with sexual maturation in boys (a) loss of milk teeth (b) increase in height (c) cracking of voice (d) weight gain

c) Cracking of voice During adolescence growth spurt occurs in both males and females, so growth velocity increases both in girls and boys.... View Article

Reproduction is essential for living organisms in order to (a) keep the individual organism alive (b) fulfil their energy requirement (c) maintain growth (d) continue the species generation after generation

d) Continue the species generation after generation Reproduction maintains a balance between the birth rate and death rate. The new... View Article

Offspring formed as a result of sexual reproduction exhibit more variations because (a) sexual reproduction is a lengthy process (b) genetic material comes from two parents of the same species (c) genetic material comes from two parents of different species (d) genetic material comes from many parents

b) Genetic material comes from two parents of the same species. Sexual reproduction is a natural way of reproduction in humans, animals and the... View Article

In Figure, the parts A, B and C are sequentially (a) cotyledon, plumule and radicle (b) plumule, radicle and cotyledon (c) plumule, cotyledon and radicle (d) radicle, cotyledon and plumule

Answer is c) Plumule, cotyledon and radicle Plumule is shoot, radicle is root and cotyledon are seed leaf.In germination process cotyledons... View Article

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 the formation of zygote (iv) Offspring formed are clones (a) (i) and (iv) (b) (i), (ii) and (iv) (c) (i), (ii) and (iii) (d) (i), (ii) and (iv)

C) (i), (ii) and (iii) The main primary function of the flower is the reproduction of the individual and the species. They are the... View Article

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 (a) (i) and (iv) (b) (ii), (iii) and (iv) (c) (iii) and (iv) (d) (i), (iii) and (iv)

b) (ii), (iii) and (iv) The flowers which contain only the male or female reproductive organs are called unisexual flowers. They are called... View Article

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 (a) (i) and (iv) (b) (ii) and (iii) (c) (i) and (iii) (d) (ii) and (iv)

d) (ii) and (iv) Flowers are a characteristic of flowering plants i.e., Angiosperms. Other plants like Bryophytes, Pteridophytes and... View Article

Length of pollen tube depends on the distance between (a) pollen grain and the upper surface of the stigma (b) pollen grain on the upper surface of stigma and ovule (c) pollen grain in anther and upper surface of stigma (d) upper surface of stigma and lower part of style

b) Pollen grain on upper surface of stigma and ovule The function of the pollen tube is to carry male gametes towards the ovary through stigma... View Article

Factors responsible for the rapid spread of bread mould on slices of bread are (i) large number of spores (ii) availability of moisture and nutrients in bread (iii) presence of tubular branched hyphae (iv) formation of round shaped sporangia (a) (i) and (iii) (b) (ii) and iv) (c) (i) and (ii) (d) (iii) and (iv)

c) (i) and (ii) The sporangium of bread mould releases numerous spores that germinate on a suitable substratum to form the hyphae. Multiple... View Article

Vegetative propagation refers to the formation of new plants from (a) stem, roots and flowers (b) stem, roots and leaves (c) stem, flowers and fruits (d) stem, leaves and flowers

b) Stem, roots and leaves Vegetative propagation is an asexual method of plant reproduction that occurs in its leaves, roots and stem. This can... View Article

In Rhizopus, tubular thread-like structures bearing sporangia at their tips are called (a) filaments (b) hyphae (c) rhizoids (d) roots

(b) hyphae Rhizopus is a genus of saprophytic and parasitic fungi. They are found in moist or damp places. They are found on organic substances... View Article

The number of chromosomes in parents and offsprings of a particular species remains constant due to (a) doubling of chromosomes after zygote formation (b) halving of chromosomes during gamete formation (c) doubling of chromosomes after gamete formation (d) halving of chromosomes after gamete formation

b) Halving of chromosomes during gamete formation Gametes are formed through a process of cell division called meiosis. This two-step division... View Article

The correct sequence of reproductive stages seen in flowering plants is (a) gametes, zygote, embryo, seedling (b) zygote, gametes, embryo, seedling (c) seedling, embryo, zygote, gametes (d) gametes, embryo, zygote, seedling

a) Gametes, zygote, embryo, seedling The male gamete is present in the pollen grain which is formed by meiotic division in the anther. The... View Article

The ability of a cell to divide into several cells during reproduction in Plasmodium is called (a) budding (b) reduction division (c) binary fission

(d) multiple fission Binary fission is a type of asexual reproduction typically observed in prokaryotes and a few single-celled eukaryotes. In... View Article

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