Question

Botany Questions. need help on these 3 please

1. there's an extra thickness to the epidermis that faces outward on a leaf, why, why is it thicker, the epidermis cells on the surface of the leaf are thicker at top, why?

2. monocots and dicots, which is knitted and which is parallel?

3. what is the function of major and minor veins ?

Answer 1

Answer of Question No 1:- There is an extra thickness to the epidermis that faces outward on a leaf because this reduces the rate of water loss from the leaf surface .

• There is a waxy , waterproof coating covering the surface of the epidermis ,This covering is called cuticle .
• Cuticle on leaves are usually thicker in
• dry or windy climates than on wet or calm environments .For example - plants that grow near the ocean have thicker cuticles to keep the ocean breezes from drying the plant out.
• The epidermis has small openings or pores called stomata. Stomata opens and close to control when gases enters and leave the leaf.

Answer of Question No. 2 -:  

Monocots have parallel veins that do not branched out, stomata on both sided of the leaf.

Dicots have knitted veins with a large central mid vein , stomata on the lower side , top and bottom cells are different..

Answer of Question No. 3 :-

The function of Major veins - transport of photosynthates.

Function of Minor veins - collection of photosynthates.