Adaptations for photosynthesis Lesson objectives :- 1.Know how plants optimise their rate of photosynthesis 2.Recap the structure of plants 3.Adapt a plant yourselves

The leaf is the main site of photosynthesis. carbon dioxide water oxygen light energy chlorophyll glucose light energy chlorophyll carbon dioxide wateroxygen

What are good features to have for photosynthesis

Leaves Obviously all plants have leaves, but what are they used for? Leaves contain chloroplasts which is where photosynthesis occurs. They also contain Stomata: this is where gases are exchanged

Stomata Stomata are found on the underside of the leaf. Its here that carbon dioxide is let in, and oxygen is let out. Water vapour is also lost through the Stomata Stoma

So leaves need Sunlight to carry out photosynthesis. Which leaf do you think will be able to get the most sunlight? A B

Plants that grow in dark shady environments often tend to have very big and broad leaves. This helps them to catch more sunlight

Controlling water losses A lot of people make the mistake and assume cacti don’t have leaves They are wrong the spikes are the cacti leaves. Remember the stomata The little holes

In Cacti they are located in the spikes. Though there are not too many stomata, in-case too much water is lost!! Cacti spikes aren’t green though, this means that there are no chloroplasts, so no photosynthesis can occur there. It only occurs in the stem

Roots Root hairs Fragile parts of cells that grow from the main root They massively increase the surface area for absorption

A plant's taproot is a straight tapering root that grows vertically down. It forms a centre from which other roots sprout. The taproot is why dandelions are hard to uproot — the top is pulled, but the long taproot stays in the ground, and re-sprouts. There are many different types of root.

Cacti and other desert plants have shallow roots that are useful for catching a lot of falling rain water.

Design your own plant Include diagrams of what it looks like, and label what its adaptations are for being good at photosynthesis. Also include a description of the habitat it exists in and say how it is adapted to that location. E.g.

The Death Bottle Plant Flower with bright patches to attract insects Cannon to fire beetles and seeds Nice big tap root Death bottles