Tag: modes of reproduction

Questions Related to modes of reproduction

$32$ chromosomes are present in the green leaf of Onion. When meiosis takes place to produce gametes after fertilization how many chromosomes will be there in triploid nucleus.

  1. $32$

  2. $16$

  3. $48$

  4. $9$


Correct Option: C

Study of fruit is known as

  1. Pomology

  2. Palynology

  3. Dendrology

  4. Anthology


Correct Option: A
Explanation:

Pomology (from Latin pomum (fruit) + logy) is a branch of botany that studies and cultivates fruit.

Development of seed from an unfertilised egg is called as 

  1. Vivipary

  2. Parthenocarpy

  3. Apomixis

  4. Apospory


Correct Option: C
Explanation:
Apomixis was defined by Hans Winkler as replacement of the normal sexual reproduction by asexual reproduction, without fertilization. Apomixis is the development of seed from maternal genotype only. Apomictically produced offspring are genetically identical to the parent plant. Male apomixis (paternal apomixis) involves replacement of the genetic material of the egg cell by that from the pollen.
Vivipary is the condition whereby the embryo are developed inside the parent. 
Parthenocarpy, development of fruit without fertilization e.g.,  pineapple, banana, cucumber, grape, orange, grapefruit, persimmon etc.
Apospory is the production of sexual generation from an asexual generation without the intervention of spores. Thus, the correct answer is option C.

After fertilization____develops into seed and___into fruit.

  1. Endosperm and Ovary

  2. Ovary and ovule

  3. Embryo sac and ovary

  4. Ovule and ovary


Correct Option: D
Explanation:

Plant fertilization is a process in which a male gamete, pollen, is transferred to the female reproductive organ to fuse with an ovule, as a part of the sexual reproduction. After fertilization, the ovule develops into a seed and the ovary develops into the fruit. 

So the answer is 'Ovule and ovary'. 

How many generation and genotypic cells are present in angiosperm seeds.

  1. Three and two respectively

  2. One and two respectively

  3. Two and three respectively

  4. One and three respectively


Correct Option: A
Explanation:
A seed contains three generations locked one within another:
(a) Parent sporophyte in the form of seed coat/coats and persistent nucellus,
(b) Female gametophyte which stores food, and
(c) Future sporophyte in the form of an embryo.
While two genotypes are from male and female gametes. 
So, the correct option is 'Three and two respectively'. 

Identify the incorrect statement.

  1. Drupe develops from monocarpellary inferior ovary with stony endocarp

  2. Phyllode is analogous to cladophyll

  3. Supporting roots arise from lower nodes in maize

  4. Axillary buds are modified into woody, pointed structures in Citrus


Correct Option: A

Seed coat is formed by

  1. Integument

  2. Nucellus

  3. Fruit wall

  4. None of the above


Correct Option: A
Explanation:

Integument is an envelope of one or more layers, each of two or more cell layers, covering the ovule, leaving only a pore, the micropyle, through which the pollen tube can enter. It may develop into the testa or seed coat. Seed coat is the outer protective covering of a seed.

Thus, the correct answer is option A.

The structures develops into the seed once fertilization has occurred is

  1. Integument

  2. Cotyledon

  3. Ovule

  4. Ovary

  5. Endosperm


Correct Option: C
Explanation:

The event of double fertilization and subsequent growth and development results in the development of ovule into the seed. Each seed contains a young plant embryo and nutritive tissue (the endosperm), both of which are surrounded by a protective seed coat (derived from integument). Monocots have persistent endosperm that serves as amain source of food in the mature seed. Eudicots endosperm nourishes the developing embryo and subsequently stores food in its cotyledons. During development of seed from an ovule following fertilization, the ovary wall surrounding it enlarges and develops into a fruit wall while ovary makes fruit. Thus, the correct answer is D

The structures that develops into the fruit once fertilization has occurred is

  1. Integument

  2. Cotyledon

  3. Ovule

  4. Ovary

  5. Endosperm


Correct Option: D
Explanation:

The event of double fertilization and subsequent growth and development results in the development of ovule into the seed. Each seed contains a young plant embryo and nutritive tissue (the endosperm), both of which are surrounded by a protective seed coat (derived from integument). Monocots have persistent endosperm that serves as a main source of food in the mature seed. Eudicots endosperm nourishes the developing embryo and subsequently stores food in its cotyledons. During development of seed from an ovule following fertilization, the ovary wall surrounding it enlarges and develops into a fruit wall while ovary makes fruit. Thus, the correct answer is D

The endosperm tissue in plants

  1. Differentiates to form root structures

  2. Provides nutrients to the plant embryo

  3. Gives rise to male gametes that make up pollen

  4. Makes up the photosynthetic cells inside the leaves

  5. Forms the tissues that transport water and nutrients


Correct Option: B
Explanation:

The endosperm is the tissue produced inside the seeds of the flowering plants by triple fusion of two central nuclei and one male nuclei in embryo sac. This tissue  surrounds the embryo and provides nutrition to it in the form of starch while in some seeds these are completely absorbed by the time they mature, in others, the endosperm is present till the seeds germinate.