Tag: plant kingdom

Questions Related to plant kingdom

In a nuclear endosperm, which of the following is seen? 

  1. Every nuclear division is followed by wall formation.

  2. Initially free-nuclear divisions followed by wall formation.

  3. First division followed by wall formation and other free nuclear.

  4. None of the above.


Correct Option: B
Explanation:

The three principal types of endosperm formation found in angiosperms—nuclear, cellular and helobial and are classified on the basis of when the cell wall forms. In nuclear endosperm formation, repeated free-nuclear divisions take place; if a cell wall is formed, it will form after free-nuclear division. In cellular endosperm formation, cell-wall formation is coincident with nuclear divisions. In helobial endosperm formation, a cell wall is laid down between the first two nuclei, after which one half develops endosperm along the cellular pattern and the other half along the nuclear pattern. 

Thus, the correct answer is option B.

Assertion : Nuclear endosperm is formed by subsequent nuclear divisions with or without wall formation.

Reason : Coconut is an example of such endosperm, where the endosperm remains nuclear throughout the development of the fruit.

  1. Both assertion and reason are true and reason is a correct explanation of the assertion.

  2. Both assertion and reason are true but reason is not a correct explanation of the assertion.

  3. Assertion is true but Reason is false

  4. Both Assertion and Reason are false

  5. Assertion is false but Reason is true


Correct Option: B
Explanation:
In free nuclear or nuclear type of endosperm the PEN undergoes multiple divisions with no or partially formed cell walls at a later stage of division.
This type of endosperm formation is observed in coconut, where the liquid or the coconut water is the free nuclear stage while the white layer formation is development of the cell wall
So, the correct answer is 'Both assertion and reason are true but reason is not a correct explanation of the assertion'

Which one of the following phytochromones is associated with seed maturation?

  1. ABA

  2. Kinetin

  3. Ethylene

  4. IAA


Correct Option: A

Mango trees do not and cannot grow in temperate regions. The most important environment factor responsible for it. 

  1. soil

  2. temperature

  3. water

  4. light


Correct Option: B
Explanation:

Temperature has a direct effect on working of enzymes. Through enzymes, it influences basal metabolite, activity and physiological functions of the organism Hence, mango trees cannot grow in temperate countries like canada and Germany. 

Ruminate endosperm occurs in the seeds of.

  1. Arecaceae

  2. Poaceae

  3. Myrtaceae

  4. Euphorbiaceous


Correct Option: A

The coconut water from tender coconut represents

  1. Free nuclear endosperm

  2. Free nuclear proembryo

  3. Fleshy mesocarp

  4. Endocarp


Correct Option: A
Explanation:
The coconut water from tender coconut represents the free nuclear or liquid endosperm. During the development of nuclear type of endosperm, the primary endosperm mother cell divides by free nuclear divisions, and these divisions are not followed by cell wall formation. Thus, the free nuclei remain in the cytoplasm of the embryo sac.
So, the correct answer is A.

In Angiosperms, endosperm is formed by

  1. Free nuclear division of megasphore

  2. Division of fused polar endosperm nuclei

  3. Division of fused secondary nucleus and male gamete

  4. Division of fused synergids and male gamete


Correct Option: C
Explanation:

The endosperm is a tissue produced inside the seeds of most of the flowering plants following fertilization. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and protein. It is formed by the fusion of secondary nucleus and one of the male gamete.

So the correct answer should be option "division of secondary nucleus and male gamete".

Choose the correct answer from the alternatives given.
An example for enucleated cell in plants is:

  1. parenchyma cell

  2. meristematic cell

  3. tracheid

  4. a mature sieve tube cell


Correct Option: D

When a heterozygous maize plant with coloured and full endosperm seed is crossed to a plant with colourless and shrunken seeds , in the progeny 480 colored full endosperm seed containing 20 colored shrunken seed containing and 20 colorless and full endosperm seed containing plants are produced What is the percentage of rfecombination?

  1. 96

  2. 4

  3. 50

  4. 2


Correct Option: A
Explanation:

When a heterozygous maize plant with coloured and full endosperm seed is crossed to a plant with colourless and shrunken seeds. In the progeny 480 coloured full endosperm seed containing 20 coloured shrunken seed containing and 20 colourless and full endosperm seed containing plants are produced. The percentage of recombinants are 38%. 

no option

Choose the correct answers from the alternatives given.
Scutdllum is

  1. a protective covering of the radicle

  2. a protective covering of the plumule

  3. an endosperm

  4. a shield-shaped cotyledon


Correct Option: D