Question

Explain how broad thin leaves are better adapted for photosynthesis compared to thick and stubby leaves.

Answer 1

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.

Broad and thin leaves have maximum surface area for absorption of CO2 and collection of sunlight. where as thick and stubby leaves are poor in these functions.

The tissue of the leaf that is especially adapted for photosynthesis :Spongy Mesophyll: this tissue contains large air spaces which are linked to the atmosphere outside the leaf through microscopic pores called stomata on the lower surface. Spongy mesophyll cells also contain chloroplasts and hence occurs .

Its main functions are photosynthesis and gas exchange. A leaf is often flat, so it absorbs the most light, and thin, so that the sunlight can get to the chloroplasts in the cells. Most leaves have stomata, which open and close. They regulate carbon dioxide, oxygen, and water vapour exchange with the atmosphere.

Adaptation	Function
Large surface area	Most leaves are broad and so have a large surface area allowing them to absorb more light.
A thin shape	A thin shape means a short distance for carbon dioxide to diffuse in and oxygen to diffuse out easily.
Chlorophyll	This chemical gives the leaves their green colour and transfers light energy to chemical energy.
Veins	Networks of veins support the structure of the leaf and transport substances to and from the cells in the leaf.
Stomata	These are small holes on the underside of the leaf that allow gases to diffuse in and out.