PHOTOSYNTHESIS

What do you need for Photosynthesis?

Four things are needed for photosynthesis:

Travels up from the roots

WATER

CARBON DIOXIDE

Enters the leaf through small holes on the underneath (stoma)

SUNLIGHT

Gives the plant energy

CHLOROPHYLL

The green pigment where the chemical reactions happen

PHOTOSYNTHESIS

What does photosynthesis

make?

PHOTOSYNTHESIS

Oxygen (waste)

Food for plant (glucose)

PHOTOSYNTHESIS

waterwater+Carbon Carbon dioxidedioxide

sugasugarr

+Oxygen

PHOTOSYNTHESIS

Oxygen (waste)

Food for plant (glucose)

The sun

Carbon dioxide from the air

Water from the soil

Where does PHOTOSYNTHESIS take

place?

Plant CellPlant Cell

Cell wall

nucleus

Cell membrane

vacuole

Chloroplasts!!

PHOTOSYNTHESIS

Chloroplasts are the GREENGREEN parts of a plant cell.

They contain a chemical called CHLOROPHYLL.CHLOROPHYLL.

Chlorophyll is a catalyst.catalyst.

A catalyst speeds up a chemical reaction, but doesn’t get used itself.

Checking for Understanding

• In which organelle or cell structure does photosynthesis occur?

A. cell wallB. cell membraneC. Golgi apparatusD. chloroplast

Four factors affect Four factors affect photosynthesis:photosynthesis:1. Light – if there is more light photosynthesis

happens faster

2. Water – if there is not enough water photosynthesis slows down

3. Temperature – the best temperature is about 300C – anything above 400C will slow photosynthesis right down

4. CO2 – if there is more carbon dioxide photosynthesis will happen quicker

Energy and Living Things

• Autotrophsorganisms that can make their own energy or food

Energy and Living Things

• Heterotrophsorganisms that must obtain energy or food from other organisms

Checking for Understanding

• What’s the ultimate source of energy for plants?

• How do heterotrophs obtain energy?

Photosynthesis

• The key cellular process that produces energy.

• Autotrophs like plants use energy from sunlight to convert water, carbon dioxide into oxygen and high energy carbohydrates.

What plants do

6CO2 + 6H2O C6H12O6 + 6O2

Carbon dioxide plus water in the presence of sunlight yield sugars/carbohydrates and oxygen.

Checking for Understanding

• In addition to chlorophyll and light, photosynthesis requires

A. water and oxygenB. water and sugarsC. oxygen and CO2

D. Water and CO2

• The products of photosynthesis are

A. sugars and oxygen

B. sugars and CO2

C. water and CO2

D. hydrogen & oxygen

How plants do it, an overview.

• The capture the energy of the sunlight with absorbing pigments.

• Pigments are housed within plant cell organelles– Chloroplasts

• Most common plant pigment is CHLOROPHYLL

Hopefully now you can be like this student.

And not like this one!