Photosynthesis Flashcards
What does ATP stand for?
Adenosine triphosphate
What does ADP stand for?
Adenosine diphosphate
What is ATP?
The energy molecule used in all living things
What type of reaction is ATP formation?
Endergonic reaction
What is the addition of a phosphate molecule to ATP called?
Phosphorylation
What is the removal of a phosphate molecule from ATP called?
Dephosphorylation; gives off energy
What does ETS stand for?
Electron Transport System
Where is the ETS always found?
Membranes
What is oxidation?
Loss of electrons; more positive charge
What is reduction?
Gaining of electrons; less positive charge
What can all autotrophs/producers/self feeders carry out?
Photosynthesis
What does photosynthesis do?
Harnesses sunlight and converts it into a form of useable energy (glucose and starch)
What is the formula for photosynthesis?
CO2 + H2O + light —-> C6H12O6 + O2 + H2O
Where does photosynthesis occur in plants?
Chloroplasts of plant cells; within the thylakoid membrane and stroma
What do chloroplasts contain?
The photosensitive pigment chlorophyll
What are carotenoids?
Other accessory pigments
What is the stroma?
Interior space of the chloroplast; dark reaction
What is the thylakoid disk?
A photosynthetic membrane; light reaction
What are grana?
Stacks of thylakoid disks
What are lamellae?
Unstacked thylakoids between grana
What is the first stage of light reactions?
Solar energy is captured and transferred to the electrons, water is split
What is photolysis?
The splitting of water with light
What is the formula for photolysis?
2H2O + light —> 4H + 4e- + O2
What are the clusters of chlorophyll within the thylakoid membrane called?
Photosystems
What happens when light hits photosystem 2?
Energy is absorbed and electrons are promoted to an electron acceptor at a higher energy level
What happens as electrons fall down the electron transport chain?
Energy is released and can be used to make ATP
What is NADP+ ?
A cofactor that aids in photosynthesis
What does NADP+ serve as?
An electron acceptor and transporter
What happens when NADP+ picks up hydrogen?
Becomes NADPH
What are the three roles/destinations of NADPH?
- Directly sent to stroma to be used in dark reaction
- Transports e- (ETS of cyclic photo-phosphorylation)
- Transports H+ (ATP synthase of chemiosmosis)
What is the second stage of light reactions?
Electron transfer and the production of ATP
What is ATP made from?
ADP + phosphate
How is ATP made?
Cyclic photo-phosphorylation and chemiosmosis
What is cyclic photo-phosphorylation?
The movement of electrons through an ETC; as electrons move down through an ETC enough energy is produced to phosphorylate ADP and ATP
What is chemiosmosis?
The movement of H+ ions down the concentration gradient, across the membrane, through an ATP synthase complex. As they do this ATP is produced. (facilitated diffusion)
What is the third stage of photosynthesis?
The Calvin Benson cycle and carbon fixation
Where does the dark reaction take place?
The stroma
What does the Calvin Benson cycle use to produce glucose?
ATP, high energy electrons, NADPH, CO2
What is RuBP?
Ribulose biphosphate; a 5 carbon sugar that acts as a CO2 acceptor
What is the resulting 6 carbon sugar split into?
Two 3 carbon PGA molecules
Using H from NADPH, what is PGA converted into?
PGAL
What can PGAL be used to produce?
Glucose, starch, sucrose, glycerol, or cellulose; or it will be recycled
How many times must the Calvin Benson cycle turn to produce one glucose molecule?
Six times
What is O2 produce from?
Photolysis
What does an endergonic reaction mean?
Energy must be added
How many times must the Calvin Benson cycle turn to produce each PGA molecule?
Three times
