191.

In the given diagram, parts labelled as A, B, C, D,  E and F are respectively identified as

• Synergids, polar nuclei, central cell, antipodals, filiform apparatus and egg

• Polar nuclei, egg, antipodals, central cell, filiform apparatus and synergids

• Egg, synergids, central cell, filiform apparatus, antipodals and polar nuclei

• Central cell, polar nuclei filiform apparatus, antipodals, synergids and egg

When two unrelated individuals or lines are crossed, the performance of F₁ hybrid in often superior to both of its parents. This phenomenon is called

• Transformation

• Heterosis

• Splicing

• Meta Morphosis

An irregular mode of reproduction resulting in the development of an embryo without fertilization is called

(I) parthenogenesis

(II) apogamy

(III) sporophytic budding

Select the correct answer using the code given below.

• Only I

• Only II

• II and III

• I, II and III

Compare the statement I and II and choose the correct option.

Statement I In the flowering plants due to higher accumulation of auxins dormancy of lateral buds occurs.

Statement II In Maryland Mammoth (a tobacco variety) flowering occurred at a different time at different latitude due to gibberellins concentration.

• Statement I is true, but II is false

• Statement I is false, but II is true

• Both statements are true

• Both statements are false

Which one of the given pollination technique/adaptation is different than others?

• Herkogamy

• Geitonogamy

• Dichogamy

• Heterostyly

Pappus helps in the dispersal of pollen in

• Asteraceae

• Brassicaceae

• Malvaceae

• Solanaceae

The one advantage of cleistogamy is

• It leads to greater genetic diversity

• Seed dispersal is more efficient and wide spread

• seed set is not dependent on pollinators

• Each visit of pollinator results in the transfer of hundreds of pollen grains

Double fertilization occurs in

• Riccia

• Pteridium

• Cycas

• Capsella

In gymnosperms, the pollen chamber represents

• A cell in the pollen grain in which the sperms are formed

• A cavity in the ovule in which pollen grains are stored after pollination

• An opening in the megagametophyte through which the pollen tube approaches the egg

• The microsporangium in which pollen grains develop

Ubisch bodies are present in

• pollen tube

• pollen grain

• microspore

• tapetum