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Multiple choice types of endosperms plant kingdom biology

Cellular endosperm can be seen in ........................

  1. Family Annonaceae

  2. Gentianaceae

  3. Adoxa Peperomia

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cellular endosperm formation - where a cell wall formation is coincident with nuclear divisions. Coconut meat is cellular endosperm. Acoraceae has cellular endosperm development while other monocots are helobial. Examples are: Gentianaceae, Adoxa and Peperomia.

Multiple choice types of endosperms plant kingdom biology

Ruminate endosperm occurs in 

  1. Cruciferae

  2. Euphorbiaceae

  3. Asteraceae

  4. Annonaceae
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Ruminate endosperm is the condition in which the endosperm is dissected by in-growths of the seed coat, is a common condition in the palms or Annonaceae. This type of  endosperm develops early and hence the in-growths are formed directly into its tissue.
Seeds of Annonaceae are characterized as possessing are one to many pistil; have a fleshy and usually brightly colored cover, have ruminate endosperm (nutritive tissue surrounding the embryo) and are oily.
hence, answer is 'Annonaceae'.
Multiple choice types of endosperms plant kingdom biology

Free nuclear divisions in the life cycle of angiosperms can be traced in .........

  1. Cellular endosperm

  2. Nuclear endosperm

  3. Helobial endosperm

  4. Both (B) and (C)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Nuclear endosperm formation - where repeated free nuclear divisions take place; if a cell wall is formed, it will form after free nuclear divisions. Commonly, referred to as liquid endosperm. Coconut juice is an example of this.
Helobial endosperm formation - where 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.

Multiple choice types of endosperms plant kingdom biology

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.
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

Multiple choice types of endosperms plant kingdom biology

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
Reveal answer Fill a bubble to check yourself
B Correct answer
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'
Multiple choice types of endosperms plant kingdom biology

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

  1. ABA

  2. Kinetin

  3. Ethylene

  4. IAA
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Abscisic acid (ABA) is the primary plant hormone associated with seed maturation, dormancy induction, and stress response. It prevents premature germination.

Multiple choice types of endosperms plant kingdom biology

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
Reveal answer Fill a bubble to check yourself
B Correct answer
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. 

Multiple choice types of endosperms plant kingdom biology

Ruminate endosperm occurs in the seeds of.

  1. Arecaceae

  2. Poaceae

  3. Myrtaceae

  4. Euphorbiaceous
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ruminate endosperm, which has an irregular or wrinkled surface, is a characteristic feature of seeds in the Arecaceae (palm) family, such as the Areca nut.

Multiple choice types of endosperms plant kingdom biology

The coconut water from tender coconut represents

  1. Free nuclear endosperm

  2. Free nuclear proembryo

  3. Fleshy mesocarp

  4. Endocarp
Reveal answer Fill a bubble to check yourself
A Correct answer
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.
Multiple choice types of endosperms plant kingdom biology

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
Reveal answer Fill a bubble to check yourself
C Correct answer
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".