Tag: androecium

Questions Related to androecium

Mature anther contains

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. One wall layer, two microsporangia

  2. Two wall layers, one microsporangium

  3. Four wall layers and four microsporangia

  4. Two wall layers, four microsporangia

Show answer
Correct Option: C
Explanation:

Structure of anther contains four wall layers:-

i)Epidermis, endothecium and middle layer that function as a protective layer.
ii)Inner most layer tapetum provide nutrition to the pollen.
iii)It contains four microsporangia two in each lobe which give rise to microspore mother cell.
So the correct option is 'Four wall layers and four microsporangia'.

Intine layer of pollen grain is made up of

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Inner cellulose, outer pectin

  2. Outer cellulose, inner pectin

  3. Only with cellulose

  4. Only with pectin

Show answer
Correct Option: A
Explanation:

  • Pollen grains are a mass of microspores in a seeded plant which appears in the form of fine dust. 
  • Each pollen grain is a minute body with varying shape and structure which are formed in the anthers of angiosperms.
  • It consists of two layers:-
1) Intine or inside layer is a thin and continuous layer made of cellulose or hemicellulose and pectin.
2) Exine or outer layer a highly decay-resistant chemical called sporopollenin.

The pollen grain is related to the embryosac as

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Male gametophyte is to the egg

  2. Male gametophyte is to the female gametophyte

  3. Sperm is to the egg

  4. Sperm is to the female gametophyte

Show answer
Correct Option: B
Explanation:

  1. The pollen grain is the male gametophyte that produces two mature male gametes vegetative and generative cell.
  2. Embryo sac is the female gametophyte that contains a thin sac within the nucellus that contains egg which is female gamete.
As male and female gamete fuse to form the egg, in same way pollen grain and embryosac related with each other to hold them.
So the correct option is 'Male gametophyte is to the female gametophyte'.

Exine of pollen grains is composed of 

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Pectocellulose

  2. Lignocellulose

  3. Sporopollenin

  4. Pollen kit

Show answer
Correct Option: C
Explanation:

Most of the pollen grains consists of three distinct parts. The central cytoplasmic part is the source of nuclei responsible for fertilization. The other parts constituting the wall of the grains are an inner layer, the intine, and an outer layer, the exine. the outer and the most durable layer, the exine, is very resistant to disintegration. The constituents of the exine have been termed as the sporopollenin.

So, the correct option is 'Sporopollenin'. 

The study of mature outer morphology of pollen grains is known as

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Polynology

  2. Palynology

  3. Andrology

  4. Microsporology

Show answer
Correct Option: B
Explanation:

The study of the mature outer morphology of pollen grains and other spores is known as palynology mainly includes pollen that is found in archaeological and geological deposits. These are used for radiocarbon dating and helps to study the ancient climate and environment by knowing the type of plant that grows at that time.

So, the correct option is 'Palynology'

The special features of the endothecium of anther is

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Maturation

  2. Nutrition

  3. Reproduction

  4. All of the above

Show answer
Correct Option: A
Explanation:

Endothecium of anther is one of the four wall layers and it helps anther by secreting certain substances that lead to the maturation of pollens.

So the correct option is 'Maturation'.

Chemically pollen kitt is made up of lipids and carotenoids.

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Pollen kitt is a sticky covering found on the surface of pollen grains. It is common in plants that are pollinated by insects. It is composed of lipids and carotenoids and is formed by tapetum. Pollen kitt helps in pollination. Hence, chemically pollen kitt is made up of lipids and carotenoids.

So, the correct answer is 'Lipids and carotenoids'.

Which one of the following is resistant to enzyme action?

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Pollen exine

  2. Leaf cuticle

  3. Cork

  4. Stem

Show answer
Correct Option: A
Explanation:

Pollen exine is formed of sporopollenin. It is resistant to acids and alkali and cannot be degraded by any enzyme. So, the correct option is 'Pollen exine'.

Which of the following event mainly affected in the absence of generative cell within pollen-grain?

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Entry of pollen-tube inside the embryo sac

  2. Double fertilization

  3. Growth of pollen-tube inside the style

  4. All of the above

Show answer
Correct Option: A

The carrier of male gametes in seed plants is

botany male & female gametophytes: structure and development pollen grain androecium male gametophyte

  1. Water

  2. Air

  3. Pollen grains

  4. Insects

Show answer
Correct Option: C
Explanation:

Seed plants are referred to angiosperms, in which seeds are present and are covered. They have male and female gametes that are responsible for fertilization. The male gametes are produced in larger numbers than the female gametes. These male gametes are the carrier of pollen grains while female gametes are the carrier of eggs or ovules. In pollination, the pollen grains are carried through wind, water or insects to the stigma of another flower.

So, the correct option is 'Water, Air, Insects, and Pollen grains'.