Chapter 15- Autotrophic Nutrition Flashcards
Autotroph
An organism that manufactures its own organic molecules such as glucose, amino acids, and fats
Organic molecules contain potential energy in form of:
organic bonds
Photosynthesis
A metabolic process where solar energy is trapped, converted to chemical energy, and then stored in the bonds of plant organic nutrient molecules.
Plants use Co2 and water to make:
glucose and oxygen
Chloroplast
Specialized organelle in plants where photosynthesis takes place. Highly organized plastid containing the chlorophyll pigment
Do photosynthetic bacteria have chloroplasts?
No, but they have membranes that function in a similar manner.
Chloroplast is bounded by:
Two membranes and contains a network of membranes called thylakoid membranes.
Chlorophyll resides within the:
thylakoid membranes
Grana
Stacks of thylaoid membranes
Stroma
fluid matrix of the chloroplast
Cofactor of chlorophyll?
Magnesium
Why is chlorophyll green?
It absorbs light in red and blue wavelengths
Two types of chlorophylls?
A and B
Photosystem
light-capturing unit of the thylakoid membrane.
What is each photosystem composed of?
A number of chlorophyll molecules. In the center is a single chlorophyll molecule coupled to other proteins that is ultimately excited by the absorbed photon.
Photosystem I: Chlorophyll A molecule is called because—
it absorbs best at 700 nm
Photosystem II= 680 nm
Net reaction of photosynthesis:
6CO2 + 12 H2O + light energy —-> C6H12O6+ 6O2+ 6H20
Light reactions
Convert solar energy into chemical energy in the form of ATP (photophosporylation) and NADH. Must take place in light.
Dark reactions
Coupled to light reactions. They incorporate Co2 into organic molecules in a process called carbon fixation.
Carbohydrates are produced by reducing CO2