C3, C4 & CAM Plants

What is carbon first incorporated into in C3 plants?

A 3-carbon compound

What is carbon first incorporated into in C4 plants?

A 4-carbon compound

Which plant type would have stomata open during the day?

C3 & C4 plants

In C3 plants, what enzyme is involved in the uptake of CO2?

RUBISCO

Where does photosynthesis take place in C3 plants?

Throught the leaf

True or false: Most plants are C4 plants

False.

In C4 Plants, what enzyme is involved in the uptake of CO2?

PEP Carboxylase

After PEP Carboxylase takes in the CO2, what happens?

The CO2 is delivered directly to RUBISCO

Examples of C3 Plants

Most plants

Examples of C4 plants

Corn, summer annual plants

Why is C4 photosynthesis good for high light intensity and high temperatures?

1. CO2 is delivered directly to RUBISCO, not allowing it to grab oxygen and undergo photorespiration.

2. Has better Water Use Efficiency because PEP Carboxylase brings in CO2 faster and so does not need to keep stomata open as much (less water lost by transpiration) for the same amount of CO2 gain for photosynthesis.

What does CAM stand for?

Crassulacean Acid Metabolism

In CAM plants, in what form would you find CO2 prior to photosynthesis?

As an acid

When are the stomata open in a CAM plant?

At night

During the night, what happens to the CO2 in a CAM plant?

It is converted into an acid and stored

What happens to the acid stored during the night in CAM plants?

It is broken down and released to RUBISCO to be used during photosynthesis

In which plant family was CAM photosynthesis first found?

Crassulaceae

In what type of conditions would you find a CAM plant?

Arid

What is CAM-idle?

When conditions are extremely arid, a CAM plant can keep its stomata closed night and day.Oxygen given off in photosynthesis is used for respiration and CO2 given off in respiration is used for photosynthesis. The plant cannot CAM-idle forever.

What is a benefit of CAM-idling?

A plant can survive dry spells and recover very quickly when water is available again

Examples of CAM plants

Succulents, agaves, orchids, bromeliads