Photosynthesis Flashcards
What would happen to a plant without energy?
These biological processes would stop, and the plant dies
- photosynthesis
- active transport
- DNA replication
- cell division
- protein synthesis
What happens to the light energy during photosynthesis?
It gets converted to chemical energy in glucose
What is photosynthesis?
The process where energy from light is used to make glucose from water and carbon dioxide
What happens to the chemical energy produced by photosynthesis?
It is stored in the plant until it is released by respiration
What is a metabolic pathway?
A process that occurs in a series of small reactions controlled by enzymes. Photosynthesis is an example of metabolic pathway.
What is a photoautotroph?
An organism that can make its own nutrients by photosynthesis (any organism that carries out photosynthesis)
How does photosynthesis provide indirect evidence for evolution?
The process of photosynthesis is common in all photoautotrophic organisms
Describe the structure of chloroplasts
1) Small, flattened organelles
2) Surrounded by a double membrane
3) Thylakoids (fluid-filled sacs) stacked up into grana
4) Grana linked together by lamellae (bits of thylakoid membrane)
Give 3 photosynthetic pigments
1) chlorophyll a
2) chlorophyll b
3) carotene
What are photosynthetic pigments?
Coloured substances that absorb light energy needed for photosynthesis
Where are photosynthetic pigments found?
In the thylakoid membrane- attached to proteins
What is a photosystem?
The protein and pigment found in the thylakoid
How many photosystems are used by plants to capture light energy and what are they?
1) Photosystem I (PSI)
- absorbs light best at a wavelength of 700 nm
2) Photosystem II (PSII)
- absorbs light best at a wavelength of 680 nm
What is the stroma?
A gel-like substance containing enzymes, sugars and organic acids
Where is the stroma found?
It is contained within the inner membrane of the chloroplast and surrounding the thylakoids
