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Photosynthesis Biolab - The second mobility in slovakia

What is photosyntesis?

this word can be separated to make two smaller words

photo - which means light

SYNTHESIS - WHICH MEANS PUTTING TOGETHER
Did you know that trees and plants can make their own food, but animals can't?
Photosyntesis is the process by which plants make their own food
To make food plants need
CARBON DIOXIDE
CO2 from the air passes through small pores in the leaves, which are called stomata
WATER
Water is absorbed by the roots and passes through vessels in the stem on its way to the leaves
SUNLIGHT
Sunlight is absorbed by a green chemical in the leaves

Photosynthesis takes place in the leaves of plants. The leaves are made up of very small cells. Inside these cells are tiny structures called

chloroplasts

each chloroplast contains a green chemical called

chlorophyll

which gives leaves their green colour

Let's sum up the knowledge about photosyntesis

plants need carbon dioxide, water and sunlight to make their food

the food they make is called glucose

in addition to glucose, plants also produce oxygen

Why is photosynthesis important?

1. provides food and energy for animals

2. produces oxygen and removes carbon dioxide from the air

What did you learn from previous labwork in Spain?

Today we're going to continue with this topic and the aim of todays labwork is

The epidermis structure of the leaf

Vocabulary you have to know

monocots - monocotyledons - they have only one cotyledon in embryo, leaf veins are parallel, roots - taproot system (grains, daffodils, banana, onions, grass...)

dicots - dicotyledons - dicot embryo has two cotyledons, leaf veins are reticulated (branched), fibrous roots (legumes, lettuce, tomato...)

stomata - is a pore, found in the epidermis of leaves, that is used to control gas exchange

Stomata open and close to allow the intake of carbon dioxide and the release of oxygen.

Stomata open when there is sunlight. Therefore, stomata are usually open during the day and closed at night

Dicotyledons usually have more stomata on the lower epidermis than the upper epidermis.

Monocotyledons have the same number of stomata on the two epidermes.

Structure of the leaf
Blade - the main part, veins - carry water &minerals to the leaf and the food the leaf makes away from the leaf,petiole - connects the leaf to the branch
Internal structure of a leaf

material tools

leaves of monocots and dipcots plants
microscope
glass microscope slides and cover glasses
dropper
preparation needle
scalpel
tweezers
PROCEDURE

1. get the upper and lower part of the leaf epidermis

2. fold the leaf and catch and loose part of epidermis

3. replace this part of epidermis by use of tweezer

4. drip a drop of water on the glass microscope slide

5. move the part of epidermis on the glass microscope slide and cover with cover glass - prepare microscope preparation

6. observe with microscope

TASKS

1. find out the structure of the upper and lower epidermis of monocots and dicots and draw it

2. find out and describe internal structure of the leaf and write the names of marked parts in the picture

3. find out where are stomata situated and write what is their importance, try to draw stomata

4. conclusion - explain the difference between monocots and dicots regard to the leaf epidermis and describe the layout of the cells in leaf blade and point out the stomata importance