Question
Question: If the diploid number of an angiospermic plant is 24, the number of chromosomes in pollen grains, en...
If the diploid number of an angiospermic plant is 24, the number of chromosomes in pollen grains, endosperm and integument will be:
A) 12,36,12
B) 12,24,36
C) 12,12,36
D) 12,36,24
Solution
Angiosperms have small pollen grains that spread genetic information from flower to flower. They include flowers who produce seeds which are enclosed within a carpel. Examples of angiospermic plants include grassed, shrubs, etc.
Complete answer:
Let’s discuss given options and find the correct answer
Each of the 3 haploid nuclei within the germinated spore grain should contain twelve chromosomes, and every of the eight nuclei among the embryo sac contain twelve chromosomes.
Pollen grains : The pollen grains are haploid in nature, therefore,
⇒2n=24⇒n=224=12
Endosperm : Endosperm is polyploid, so it's going to have 3n chromosomes.
⇒n=12⇒3n=3×12=36
Integument : Integument is diploid in nature, therefore, it is going to have 2n chromosomes,
⇒n=12⇒2n=2×12=24
Hence the correct answer is option ‘D’ 12, 36, 24.
Additional information: The carpel is known as the female reproductive organ of the angiosperms. It is also known as a pistol and together with all the female parts it is known as gynoecium.
Note:
i) Angiosperms have male sex organs referred to as stamens. Stamen is also known as microsporophyll and consists of two parts - anther and filament.
ii) Filament - It's a long and slender stalk like structure
iii) Anther - It is a lobed structure present in filament and can be monothecous or dithecous