Cellular Energy: Photosynthesis Flashcards
Overview of photosynthesis
Using light energy from the sun which is trapped by the chlorophyll, water absorbed by the roots, and CO2 which enters through the stomata in the bottoms of the leaves, the chloroplasts and enzymes make glucose which is converted into starch (polysaccharide- which is stored in other parts of the plant) and give off oxygen into the air.
Fun fact! What do polysaccharides like starch do in iodine?
They turn it blue!
Chemical formula for photosynthesis
Photons+ 6 CO2+ 12 H2O—>(chloroplast/enzyme) C6H12O6+ 6 O2+ 6 H2O.
What is a photon?
It is a unit of light energy that can be absorbed by plant pigments.
Why does a leaf usually look green to humans?
It absorbs all wavelengths of light except green, which it reflects.
What part of the light spectrum can humans see?
The rainbow, no ultraviolet or anything else.
Where does photosynthesis occur?
In the chloroplasts of the leaves.
What happens during the light dependent reaction?
The electrons in the chlorophyll absorb photon energy and are excited to higher energy levels. As they return to normal (ground state), the energy is used to connect a phosphate to ADP to make ATP. This energy also splits water: H2O—> H + O2. The O2 is released.
When can plants photosynthesize?
Anytime there is sunlight.
What is the light independent reaction/Calvin cycle?
The ATP made in the light dependent reaction makes the hydrogen that was made when the water split combine with CO2 to make glucose (C6H12O6).
How is the glucose made in the Calvin cycle stored?
As starch or cellulose.
What is one adaption of plants to conserve water?
They can close their stomata on the undersides of their leaves to prevent water from escaping.
What is the “stack of coins” called that is where the light hits inside the chloroplast?
Thylakoid.
What light is best for plants to photosynthesize? Which is worst?
Best= red or blue, worst= green.
