All Free Biology MCQs with Answers

• A. Single sperm and two vegetative cells
• B. Three sperms
• C. Two sperms and a vegetative cell
• D. Single sperm and a vegetative cell.

Explanation: The protoplast of the male gametophyte divides mitotically to produce two unequal cells - a small generative cell and a large vegetative…

• A. Apogamy
• B. Cleistogamy
• C. Geitonogamy
• D. Xenogamy

Explanation: Geitonogamy involves the transfer of pollen from one flower of a plant to the stigma of another flower of the same plant.

• A. Fruit, where style was present
• B. Seed, where micropyle was present
• C. Seed, where funicle was attached
• D. Fruit, where it was attached to the pedicel

Explanation: Ovule is an integumented megasporangium found in spermatophytes which develops into seed after fertilization.

• A. Sargassum
• B. Ectocarpus
• C. Ulothrix
• D. Spirogyra

Explanation: A. Sargassum: Sargassum is a brown alga that reproduces sexually. However, it does not exhibit isogamy with non-flagellated gametes.

• A. Fertilization of a flower by the pollen from another flower of the same plant
• B. Fertilization of a flower by the pollen from the same flower
• C. Fertilization of a flower by the pollen from a flower of another plant in the same population
• D. Fertilization of a flower by the pollen from a flower of another plant belonging to a distant population

Explanation: Geitonogamy is the pollination taking place between the two flowers of the same plant or genetically similar plant.

• A. Maize
• B. Castor
• C. Wheat
• D. Pea

Explanation: In majority of dicot seeds,including pea,the endosperm is consumed during seed development and the food is stored in cotyledons and other…

• A. Gemmule
• B. Megaspore
• C. Meiocyte
• D. Conidia

Explanation: Gemmule and conidia are asexual propagules thus no meiosis takes place in them.

• A. No dependence on pollinators
• B. Vivipary
• C. Higher genetic variability
• D. More vigorous offspring

Explanation: Cleistogamy is the process of pollination and fertilization before the flower has opened.

• A. Nucellus
• B. Ovule
• C. Embryo Sac
• D. Fruit

Explanation: In angiosperms, the body of the ovule consists of a mass of parenchymatous cells called nucellus, which is equivalent to megasporangium.

• A. Papaya
• B. Cucumber
• C. Castor
• D. Maize

Explanation: Papaya is dioecious i.e. male and female occur in a separate plant so that it prevents both autogamy and geitonogamy (methods of…

• A. Cuticle
• B. Sporopollenin
• C. Lignin
• D. Cellulose

Explanation: Sporopollenin is a major component of the tough outer (exine) walls of spores and pollen grains.

• A. Onion-Bulb
• B. Ginger-Sucker
• C. Chlamydomonas-Conidia
• D. Yeast-Zoospores

Explanation: Yeast and other ascomycetes characteristically produce ascospores. Chlamydomonas is an alga and conidia are not found in algae.

• A. Commelina
• B. Zostera
• C. Salvia
• D. Figs

Explanation: plants such as Viola (common pansy), Oxalis, and Commelina produce two types of flowers­ chasmogamous flowers which are similar to flowers…

• A. Geitonogamy
• B. Xenogamy
• C. Chasmogamy
• D. Cleistogamy

Explanation: Cleistogamy is a type of autogamous pollination where a flower remains closed and self-pollinates without the need for external agents…

• A. Root buds
• B. Flower buds
• C. Shoot buds
• D. Axillary buds

Explanation: The "eyes" of a potato tuber are actually small, dormant shoots or buds.

• A. Both are applicable to only dicot plants
• B. Both bypass the flowering phase
• C. Both occur round the year
• D. Both produce progeny identical to the parent

Explanation: Both vegetative reproduction and apomixis result in offspring that are genetically identical (clones) to the parent plant.

• A. Synergids
• B. Maternal sporophytic tissue in ovule
• C. Antipodal cells
• D. Diploid egg

Explanation: Apomictic embryos in Citrus arise from maternal sporophytic tissue in the ovule.

• A. Xenogamy
• B. Geitonogamy
• C. Karyogamy
• D. Autogamy

Explanation: Geitonogamy is the transfer of pollen grains from the anther of one flower to the stigma of another flower on the same plant.

• A. Small, brightly coloured, producing large number of pollen grains
• B. Small, producing large number of dry pollen grains
• C. Large producing abundant nectar and pollen
• D. Small, producing nectar and dry pollen

Explanation: Wind-pollinated flowers are typically small and produce a large quantity of dry pollen grains.

• A. Option A
• B. Option B
• C. Option C
• D. Option D

Explanation: A - offset of water hyacinth (Eichhornia) B - Antheridiophore of Marchantia C - Antipodals of the mature embryo sac D - Oogonium of Chara