Go through the following statements:
a. Flowers are small. They are often packed in inflorescence
b. Flowers are colourless, nectarless and odourless
c. Well exposed stamens
d. Pollen grains - produced in large number, light, non-sticky
e. Flowers often have a single ovule in each ovary
f. Stigma - large, often feathery.
The above contrivances favour:
(1) Self pollination
Find out the correct option:
(1) Among animals, insects, particularly bees are the dominant biotic pollinating agents
(2) Often flowers of animal- pollinated plants are specially adapted for particular species of animals
(3) In some species floral rewards like edible nectar, pollen grains, shelter for egg laying are given to pollinating animals
(4) All the above are correct
a. Flowers are usually large, colourful, fragrant
b. Pollen grains are produced in large number
c. Pollen grains are light in weight and non-sticky
d. Sticky pollen grains
e. Stigma inserted and sticky
f. Edible pollen grains and nectar.
Which of the above characters favour entomophily?
(1) II, IV, V
(2) I, II, III, VI
(3) III, IV, V
(4) I, IV, V, VI
I. Is a device to prevent inbreeding
II. Provides a biochemical block to self-fertilization.
III. Ensures cross-fertilization.
IV. Is governed by pollen-pistil interaction
V. Is governed by series of multiple alleles.
VI. Prevents self pollen (from the same flower or other flowers of the same plant) from fertilizing the ovules inhibiting pollen germination or pollen tube growth in the pistil.
(1) All are correct
(2) All are wrong
(3) Only I, II, III are correct
(4) IV and V are wrong
Which of the following options is correct?
(1) Pollination gives the guarantee of the promotion of post-pollination events that lead to fertilization
(2) The events – “from pollen deposition on stigma until pollen tubes enter the ovule" are together referred to as pollen-pistil interaction
(3) Pollen-pistil interaction is a dynamic process involving pollen recognition followed by only promotion (not rejection) of the pollen
(4) Pistil has no ability to recognize the pollen, whether right or wrong type
In double fertilization total number of male nuclei and total number of female nuclei involved are:
(1) 3, 2 respectively
(2) 2, 3 respectively
(3) 2, 2 respectively
(4) 3, 3 respectively
A homogamous tall pistillate plant (TT) is crossed with homogamous dwarf staminate plant (tt). What is the genotype of endosperm?
For artificial hybridisation experiment in bisexual flower, which of the sequences is correct?
(1) Bagging → Emasculation → Cross pollination → Rebagging
(2) Emasculation → Bagging → Cross pollination → Rebagging
(3) Cross pollination → Bagging → Emasculation → Rebagging
(4) Self-pollination → Bagging → Emasculation → Rebagging
Which of the following is false?
I. Endosperm formation starts prior to first division of zygote
II. Angiospermic endosperm is mostly 3N while gymnospermic one is N.
III. The most common type of endosperm is nuclear.
IV. Coconut has both liquid nuclear (multinucleate) and cellular endosperm.
V. Milky water of green tender coconut is liquid female gametophyte.
(1) I and II only
(2) III only
(3) V only
(4) II only
Diagram given below shows stages in embryogenesis in a typical dicot (Capsella). Identify structures A to D respectively:
(a) Suspensor, Radicle, Plumule, Cotyledons
(b) Hypophysis, Radicle, Plumule, Cotyledons
(c) Suspensor, Plumule, Radicle, Cotyledons
(d) Suspensor, Radicule, Plumule, Hypocotyls