Biology
Assertion (A): Calyx is the outermost whorl of a flower which consists of large, fragrant and brightly coloured petals.
Reason (R): As petals are brightly coloured and fragrant, they can be noticed by insects easily and help in cross pollination.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Answer
A is false and R is true.
Explanation — A is false as calyx, the outermost whorl of a flower consists of tiny leaf-like green structures called sepals, for providing the inner parts of flower with necessary protection.
R is true as corolla, the second inner whorl of the flower is made up of petals that are large, fragrant and brightly coloured. They can be noticed by insects easily and help in cross pollination.
Therefore, A is false and R is true is the correct option.
Related Questions
Cross-pollination is considered better than self-pollination because it produces healthier and more viable seeds. But it cannot occur by itself. Cross-pollination occurs with the help of certain agents like wind, water, insects, etc. Which of the following features of flowers are not suitable for insect-pollination ?
P. Flowers are usually small and of dull colours.
Q. Flowers are not scented and do not produce nectar.
R. Flowers produce sticky pollen grains.- Only Q
- Only Q and R
- Only P and R
- Only P and Q
Assertion (A): Carrot is a biennial plant which stores food material in its roots in the first year.
Reason (R): This food is utilized in the second year to produce flowers and viable seeds, i.e. to reproduce sexually.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): Micropropagation is the propagation or multiplication of plants by a special technique called 'tissue culture'.
Reason (R): It is called 'micropropagation' because this technique is applicable to micro-organisms only.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): Vallisneria shows a special adaptation for hydrophilous pollination.
Reason (R): Its male flowers get detached from the plant and float freely until they reach and make physical contact with the female flowers at the water surface.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.