Latest Posts

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 Explanation Reproduction maintains a balance between the birth rate and death rate. The... 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. Explanation Sexual reproduction is a natural way of reproduction... 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 Explanation Plumule is shoot, radicle is root and cotyledon are seed leaf.In germination... 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) Explanation The main primary function of the flower is the reproduction of the individual and... 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) Explanation The flowers which contain only the male or female reproductive organs are called unisexual... 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) Explanation Flowers are a characteristic of flowering plants i.e., Angiosperms. Other plants like Bryophytes, Pteridophytes and Gymnosperms... 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 Explanation The function of the pollen tube is to carry... 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) Explanation The sporangium of bread mould releases numerous spores that germinate on a suitable substratum to... 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 Explanation Vegetative propagation is an asexual method of plant reproduction that occurs in its leaves,... 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 Explanation Rhizopus is a genus of saprophytic and parasitic fungi. They are found in moist or damp places.... 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 Explanation Gametes are formed through a process of cell division called meiosis. This... 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 Explanation The male gamete is present in the pollen grain which is formed by meiotic... 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 Explanation Binary fission is a type of asexual reproduction typically observed in prokaryotes and a few single-celled... View Article

In Spirogyra, asexual reproduction takes place by (a) breaking up of filaments into smaller bits (b) division of a cell into two cells (c) division of a cell into many cells (d) formation of young cells from older cells.

a) Breaking up of fragments into smaller bits. Explanation Spirogyra undergo vegetative, asexual and sexual reproduction. The life cycle of... View Article

A feature of reproduction that is common to Amoeba, Spirogyra and Yeast is that (a) they reproduce asexually (b) they are all unicellular (c) they reproduce only sexually (d) they are all multicellular

a) They reproduce asexually b) They are all unicellular Explanation Asexual reproduction is a mode of reproduction in which a... View Article

Characters that are transmitted from parents to offspring during reproduction show (a) only similarities with parents (b) only variations with parents (c) both similarities and variations with parents (d) neither similarities nor variations

c) Both similarities and variations with parents Explanation Characters that are transmitted from parents to offspring shows both similarity and... View Article

Characters transmitted from parents to offspring are present in (a) cytoplasm (b) ribosome (c) Golgi bodies (d) genes

d) Genes Explanation The characteristics that are transmitted from parents to offspring are present in genes. Genes are present on... View Article

Offspring formed by asexual method of reproduction have greater similarity among themselves because (i) asexual reproduction involves only one parent (ii) asexual reproduction does not involve gametes (iii) asexual reproduction occurs before sexual reproduction (iv) asexual reproduction occurs after sexual reproduction (a) (i) and (ii) (b) (i) and (iii) (c) (ii) and (iv) (d) (iii) and (iv)

(a) (i) and (ii) Explanation In sexual reproduction, fusion of male and female gamete takes place. So, mixing of genetic... View Article

Which of the following is the correct sequence of events of sexual reproduction in a flower? (a) pollination, fertilisation, seedling, embryo (b) seedling, embryo, fertilisation, pollination (c) pollination, fertilisation, embryo, seedling (d) embryo, seedling, pollination, fertilization

(c) Pollination, fertilisation, embryo, seedling Explanation In flowers, the pollen grain germinates after the pollination of the carpel and grows... View Article

In a flower, the parts that produce male and female gametes (germ cells) are (a) stamen and anther (b) filament and stigma (c) anther and ovary (d) stamen and style

(c) anther and ovary Explanation The anther is a yellowish, sac-like structure, involved in producing and storing the pollens. Ovary:... View Article

«
1
…
1,445
1,446
1,447
1,448
1,449
…
5,472
»