Question

Transmission tissue is characteristic feature of ________
A. Dry stigma
B. Wet stigma
C. Hollow style
D. Solid style

Answer 1

Hint: Transmission tissues are specialized tissues present in the style of the carpel of the flower. This transmission tissue helps in fertilization of male and female gametes through making a pollen tube which connects the stigma of the flower with the inside of the ovary.

Complete answer:
Plants reproduce by sexual reproduction method in which male and female reproductive organs present in the flower form male and female gametes respectively, and then pollens that is, male gametes fall on stigma of female reproductive organ and fertilisation take place in the ovary of female reproductive part. After fertilization, zygote develops into a new individual.
Thus, when pollen lands on the stigma of the female pollen tube matures and connects it to the internal ovary. The tissues present in this pollen tube are called transmitting tissues.
Style or pollen tube is made up of two types:
Hollow style: This is a stylar canal which is lined by glandular cells. These cells mainly are multinucleated and have polyploid condition. This section is rich with nutrients like carbohydrates and proteins and it shows activity of different enzymes like esterase and acid phosphatase.
Solid style: This has a tissue responsible for transmission of pollen from stigma to ovary. It is made up of thin walled cells.
The cells of this tube are connected with the help of plasmodesmata which is present in both transverse and longitudinal walls of the pollen tube or style.

Thus, the correct option is option ‘D’ which is solid style.

Note: These are cylindrical tissues which are located at the centre of the solid style. Style Is outer covering of pollen tube. When we observe these cells under a microscope with a transverse section, these appear roundish in shape and when they are seen with a longitudinal section, they are elongated.