Photosynthesis

These flashcards cover key concepts, definitions, and processes related to photosynthesis as per the lecture notes.

What is photosynthesis?

The build-up of carbohydrates from carbon dioxide and water using radiant energy from the sun trapped by chlorophyll, releasing oxygen.

What are the main requirements for photosynthesis?

Carbon dioxide, water, radiant energy, chlorophyll, and enzymes.

Where does photosynthesis take place?

In the chloroplast.

What is the primary product of photosynthesis?

Glucose, which is stored as starch.

What are the two stages of photosynthesis?

The light phase (light-dependent) and the dark phase (light-independent).

What is the role of chlorophyll in photosynthesis?

To trap radiant energy from sunlight.

What happens during the light phase of photosynthesis?

Radiant energy is absorbed, converted into chemical energy, and used for photolysis and ATP formation.

What is photolysis?

The process where water molecules are split into energy-rich hydrogen atoms and oxygen atoms.

What occurs during the dark phase of photosynthesis?

Carbon dioxide combines with energy-rich H-atoms forming glucose, using energy from ATP.

What is the significance of photosynthesis to the environment?

It maintains oxygen and carbon dioxide levels and provides food for heterotrophic organisms.

How does light intensity affect the rate of photosynthesis?

An increase in light intensity generally increases the rate of photosynthesis until a limit is reached.

What is the optimal temperature for photosynthesis?

Plants photosynthesize optimally at 25°C.

What effect does carbon dioxide concentration have on photosynthesis?

Increasing carbon dioxide concentration increases the rate of photosynthesis.

What adaptations do leaves have for photosynthesis?

Transparent to allow light penetration, thin walls for gas exchange, and abundant chloroplasts to trap light.

What is the practical way to test for starch in a leaf?

Expose a leafy plant to sunlight, boil it to kill cells, soak it in alcohol, and test with iodine solution.