Biology Chapter 8
How is ATP produced in the light reactions?
A gradient H+ ions build up in the lumen of the thylakoids. It's used to power the synthesis of ATP from ADP and inorganic phosphorus using ATP synthase.
Summarize the process of photosynthesis as a chemical equation:
6 CO2 + 6 H20 + light = C6H12O6 + 6 O2
What is the main product of the Calvin cycle?
A 3-carbon molecule that is the building block of sugars such as glucose.
What products of the light-dependent reactions are used in the light-independent reactions?
ATP and NADPH.
What is the name of the enzyme involved?
ATP synthase.
What compound do cells use to store and release energy?
ATP.
What components make up the compound ATP?
Adenosine, ribose, and phosphate groups.
Why is water needed as a reactant in the light reactions?
Because it is a reactant in the equation.
Why do plants appear as green?
Because it is the color that plants don't absorb much of so they are reflected by the plant leave and which we perceive as green.
Why are decomposers, such as mushrooms, considered heterotrophs and not autotrophs?
Because mushrooms obtain energy from the food that they eat.
Most cells have only small amount of ATP so it is not a good molecule to store large amounts of energy over the long term. What do cells use instead for generating needed energy?
Carbohydrates.
Summarize the process of photosynthesis in words:
Carbon dioxide + water + light = sugars + oxygen
In what organelle does photosynthesis take place?
Chloroplast.
How do plants capture energy from sunlight?
Energy is captures by pigments such as chlorophyll.
Where does the CO2 used in the Calvin cycle come from?
From the atmosphere through the leaf's stomata.
Where does the ATP and NADPH used in the Calvin cycle come from?
From the light-dependent reactions that take place in the thylakoid membrane.
Where is the energy stored in the molecule ATP?
In the phosphate bonds.
Where do the light-independent reaction occur?
In the stroma.
Where do the light reaction take place?
In the thylakoid membranes.
What are reactants (inputs) and products (outputs) of photosynthesis?
Inputs: Carbon Dioxide, light, and water Outputs: Sugars and oxygen
What is the role of light in photosynthesis?
Light energy absorbed by pigments produces high-energy (H+) electrons that are used to convert NADP+ and ADP into NADPH and ATP, trapping the energy in chemical form.
What are the two products of the light reactions?
NADPH and ATP.
What is the name of the carrier used in photosynthesis?
NADPH and ATP.
What does the sunlight that is absorbed by pigments in the chloroplast provide to the light reactions?
Sunlight provides the energy to split water molecules that provide electrons to the chlorophyll pigments.
What happens to the ATP molecules produced?
The ATP produced is made on the stromal side of the thylakoids where it is used in the Calvin cycle to make sugars from CO2.
What two processes make up photosynthesis?
The light-dependent and light-independent reactions.
What are electron carrier molecules?
These are various proteins that undergo a series of oxidation and reduction reactions to pass through the ETC until NADPH is produced.
Summarize what happens in the light-dependent reactions:
These reactions use energy from the sunlight to produce oxygen and convert ADP and NADP+ into the energy carriers ATP and NADPH.
What does water specifically provide to these reactions?
Water is split to provide high-energy electrons, H+ ions, and oxygen.