Thylakoids
in chloroplasts
saclike photosynthetic membranes
Granum
stack of thylakoids
Stroma
region outside the thylakoid membranes in the chloroplasts
Two stages of photosynthesis
light and dark reaction
When sunlight excites electrons in chlorophyll, how do the electrons change?
they gain a great deal of energy
carrier molecule
a compound that can accept a pair of high energy electrons and transfer them along with most of their energy to another molecule
carrier molecule involved in photosynthesis
NADP+
How does NADP+ become NADPH?
it accepts and holds 2 high energy electrons along with a hydrogen ion
Light dependent reactions...
convert ADP into ATP
they produce oxygen gas
where do the light-dependent reactions take place?
thylakoid membranes of chloroplasts
Light-dependent reactions also do this in their process...
high-energy electrons move through the electron transport chain from photosystem 2 to photosystem 1
photosythesis begins when pigments in photosystem 1 absorb light
difference in charges across the thylakoid membrane provides the energy to make ATP
pigmen
How does ATP synthase produce ATP?
ATP synthase bonds ADP and a phosphate group together to produce ATP
ATP
one of the principal chemical compounds that cells use to store and release energy
NADP+
a carrier molecule compound that accepts and hold 2 high energy electrons along with H+
ATP synthase
a protein that spans the membrane and allows H+ ions to pass through it
Calvin Cycle
plants use the energy that ATP and NADPH contain to build high energy compounds that can be stored for a long time
which part of photosynthesis is oxygen produced?
when the energy of the sun converts water and carbon dioxide into oxygen (and sugars)
difference between light-dependent reactions and the calvin cycle?
light dependent don't store as much energy as long as the calvin cycle does
what compounds are formed from the carbon dioxide in the calvin cycle?
sugars, lipids, amino acids, and other compounds
what does the calvin cycle use to produce high-energy sugars?
energy that ATP and NADPH contain
why are reactions of the calvin cycle also called light-dependent reactions?
they both use ATP, NADPH, and oxygen
Things that are in the Calvin cycle?
main products are 6 carbon dioxide molecules
carbon dioxide molecules enter the Calvin cycle from the atmosphere
energy from ATP and high-energy electrons from NADPH are used to convert 3-carbon molecules into higher energy forms
3 factors that affect the rate at which photosynthesis occurs?
shortage of water
temps. above or below 0 C and 35 C may damage enzymes which slow down the reaction
intensity of the light- to high (plant reaches max. rate of photosynthesis)
What is released when the chemical bond is broken between the second and third phosphates of an ATP molecule?
energy