STRUCTURES AND

FUNCTIONS OF THE LEAF

What is the Leaf’s Job?

The leaf is the main food-making part of the plant.

Think of the leaf as a factory that makes food, or sugar, for the plant.

The Leaf’s Structures

Veins in the plant carry water to the leaf.

Epidermis- the leaf’s top and bottom, outermost protective layer that keeps the leaf from losing water.

Epidermis

The Stomata Stomata- pores in the bottom of leaves that

open and close to let in air or give off water vapor.

The stomata is the entrance/exit to the leaf. Carbon dioxide comes in. Extra water vapor and oxygen go out.

View this segment to see “How a Plants Gets Air.”http://www.unitedstreaming.com/search/assetDetail.cfm?guidAssetID=05D365B6-A1A5-4BC8-8A8A-B6595F48077C

Chlorophyll

Chlorophyll is a green substance made inside the middle of the leaf.

Chlorophyll gives plants their green color.

It also traps the energy

from sunlight.

Photosynthesis Photosynthesis-

when plants use energy from sunlight to make food from water and carbon dioxide.

Oxygen is released as the waste product.

3 Ingredients for Photosynthesis

Water, Carbon dioxide, Sunlight

Water is absorbed by the roots and is sent through the stem to the leaf.

Carbon dioxide enters the leaf through the stomata.

Chlorophyll in the leaf traps sunlight.View this segment on “Photosynthesis.”http://www.unitedstreaming.com/search/assetDetail.cfm?guidAssetID=6B4E1452-2067-4495-807D-9A4E722D8CAC

Sweating It Out

Transpiration- a plant’s release of excess water through the stomata.

This is why plants “dry up” and die when not watered properly.

A Little Energy Boost

Respiration- the plant’s sugars, or food, is broken down by oxygen. This gives the plant energy.

This is sort of like how our bodies break down food to give us energy.