Question

Appreciate the structure of leaves

Answer 1

A leaf is a plant organ and is made up of a collection of tissues in a regular organisation. The major tissue systems present are:

The epidermis that covers the upper and lower surfaces

The mesophyll (also called chlorenchyma) inside the leaf that is rich in chloroplasts

The arrangement of veins (the vascular tissue)

Answer 2

Leaves enable photosynthesis to occur. Photosynthesis is the process by which leaves absorb light and carbon dioxide to produce carbohydrate (food) for plants to grow. Leaves are adapted to perform their function, eg they have a large surface area to absorb sunlight.
Plants have two different types of 'transport' tissue, xylem and phloem, that move substances in and around the plant. When water evaporates from the leaves, resulting in more water being drawn up from the roots, it is called transpiration.
Structure of a leaf
Functions of leaves
The function of a leaf is photosynthesis – to absorb light and carbon dioxide to produce carbohydrates. The equation for photosynthesis is:
Carbon dioxide and water → glucose and oxygen
Did you know:
* Leaves are the source of all of food on the planet
* Leaves recycle all of the world's carbon dioxide in the air
* Leaves contain the world's most abundant enzyme


Leaves are adapted in several ways to help them perform their function.
Features of leaves
Adaption
Purpose
Large surface area
To absorb more light
Thin
Short distance for carbon dioxide to diffuse into leaf cells
Chlorophyll
Absorbs sunlight to transfer energy into chemicals
Network of veins
To support the leaf and transport water and carbohydrates
Stomata
Allow carbon dioxide to diffuse into the leaf
Inside the leaf


The internal structure of the leaf is also adapted to promote efficient photosynthesis:
Structure of leaves
Adaption
Purpose
Epidermis is thin and transparent
To allow more light to reach the palisade cells
Thin cuticle made of wax
To protect the leaf without blocking out light
Palisade cell layer at top of leaf
To absorb more light
Spongy layer
Air spaces allow carbon dioxide to diffuse through the leaf, and increase the surface area
Palisade cells contain many chloroplasts
To absorb all the available light


Im not sure