Chapter 2 – Sexual Reproduction In Flowering Plants

Among the terms listed below, those that of are not technically correct names for a floral whorl are: i. Androecium ii. Carpel iii. Corolla iv. Sepal

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

Embryo sac is to ovule as _______ is to an anther.

• a.Stamen
• b.Filament
• c.Pollen grain
• d.Androecium

In a typical complete, bisexual and hypogynous flower the arrangement of floral whorls on the thalamus from the outermost to the innermost is:

• a.Calyx, corolla, androecium and gynoecium
• b.Calyx, corolla, gynoecium and androecium
• c.Gynoecium, androecium, corolla and calyx
• d.Androecium, gynoecium, corolla and calyx

A dicotyledonous plant bears flowers but never produces fruits and seeds. The most probable cause for the above situation is:

• a.Plant is dioecious and bears only pistillate flowers
• b.Plant is dioecious and bears both pistillate and staminate flowers
• c.Plant is monoecious
• d.Plant is dioecious and bears only staminate flowers.

The outermost and innermost wall layers of microsporangium in an anther are respectively:

• a.Endothecium and tapetum
• b.Epidermis and endodermis
• c.Epidermis and middle layer
• d.Epidermis and tapetum

During microsporogenesis, meiosis occurs in:

• a.Endothecium
• b.Microspore mother cells
• c.Microspore tetrads
• d.Pollen grains.

From among the sets of terms given below, identify those that are associated with the gynoecium.

• a.Stigma, ovule, embryo sac, placenta
• b.Thalamus, pistil, style, ovule
• c.Ovule, ovary, embryo sac, tapetum
• d.Ovule, stamen, ovary, embryo sac

Starting from the innermost part, the correct sequence of parts in an ovule are,

• a.egg, nucellus, embryo sac, integument
• b.egg, embryo sac, nucellus, integument
• c.embryo sac, nucellus, integument, egg
• d.egg, integument, embryo sac, nucellus.

From the statements given below choose the option that are true for a typical female gametophyte of a flowering plant: i. It is 8-nucleate and 7-celled at maturity ii. It is free-nuclear during the development iii. It is situated inside the integument but outside the nucellus iv. It has an egg apparatus situated at the chalazal end

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

Autogamy can occur in a chasmogamous flower if:

• a.Pollen matures before maturity of ovule
• b.Ovules mature before maturity of pollen
• c.Both pollen and ovules mature simultaneously
• d.Both anther and stigma are of equal lengths. SEXUAL REPRODUCTION IN FLOWERING PLANTS 11

Choose the correct statement from the following:

• a.Cleistogamous flowers always exhibit autogamy
• b.Chasmogamous flowers always exhibit geitonogamy
• c.Cleistogamous flowers exhibit both autogamy and geitonogamy
• d.Chasmogamous flowers never exhibit autogamy

A particular species of plant produces light, non-sticky pollen in large numbers and its stigmas are long and feathery. These modifications facilitate pollination by:

• a.Insects
• b.Water
• c.Wind
• d.Animals.

From among the situations given below, choose the one that prevents both autogamy and geitonogamy.

• a.Monoecious plant bearing unisexual flowers
• b.Dioecious plant bearing only male or female flowers
• c.Monoecious plant with bisexual flowers
• d.Dioecious plant with bisexual flowers

In a fertilised embryo sac, the haploid, diploid and triploid structures are:

• a.Synergid, zygote and primary endosperm nucleus
• b.Synergid, antipodal and polar nuclei
• c.Antipodal, synergid and primary endosperm nucleus
• d.Synergid, polar nuclei and zygote.

In an embryo sac, the cells that degenerate after fertilisation are:

• a.Synergids and primary endosperm cell
• b.Synergids and antipodals
• c.Antipodals and primary endosperm cell
• d.Egg and antipodals.

While planning for an artificial hybridization programme involving dioecious plants, which of the following steps would not be relevant:

• a.Bagging of female flower
• b.Dusting of pollen on stigma
• c.Emasculation
• d.Collection of pollen

In the embryos of a typical dicot and a grass, true homologous structures are:

• a.Coleorhiza and coleoptile
• b.Coleoptile and scutellum
• c.Cotyledons and scutellum
• d.Hypocotyl and radicle.

The phenomenon observed in some plants wherein parts of the sexual apparatus is used for forming embryos without fertilisation is called:

• a.Parthenocarpy
• b.Apomixis
• c.Vegetative propagation
• d.Sexual reproduction.

In a flower, if the megaspore mother cell forms megaspores without undergoing meiosis and if one of the megaspores develops into an embryo sac, its nuclei would be:

• a.Haploid
• b.Diploid
• c.A few haploid and a few diploid
• d.With varying ploidy.

The phenomenon wherein, the ovary develops into a fruit without fertilisation is called:

• a.Parthenocarpy
• b.Apomixis
• c.Asexual reproduction
• d.Sexual reproduction