Chapter 10: Plant Photosynthesis and Respiration

Study flashcards for Chapter 10 covering the essential vocabulary and concepts related to plant photosynthesis and respiration.

Photosynthesis

Converts light energy to a usable form.

Respiration

Releases stored energy from glucose.

Metabolism

Sum of all interrelated biochemical processes in living organisms.

Anabolism

Forming chemical bonds to build molecules.

Catabolism

Breaking chemical bonds to release energy.

Oxidation

Loss of electron(s) from a compound.

Reduction

Gain of electron(s) by a compound.

Light-dependent reactions

Reactions in thylakoid membranes that produce ATP and NADPH.

Light-independent reactions

Reactions in stroma that utilize ATP and NADPH to form sugars.

Chloroplasts

Organelles in plant cells where photosynthesis takes place.

Chlorophyll

Pigment that captures light for photosynthesis.

Carbohydrates

Molecules produced during photosynthesis that provide energy.

ATP

Adenosine triphosphate, energy currency of the cell.

NADPH

Molecule that carries electrons used in light-independent reactions.

Calvin cycle

Cycle in photosynthesis where carbon dioxide is fixed into sugars.

Photorespiration

Process that competes with photosynthesis by fixing oxygen instead of carbon dioxide.

C4 Plants

Plants that utilize a 4-carbon pathway for carbon fixation.

CAM Photosynthesis

Metabolism that allows plants to fix carbon dioxide at night.

Thylakoid membrane

Membrane system within chloroplasts where light-dependent reactions occur.

Phycobilins

Photosynthetic pigments found in cyanobacteria and red algae.

PEP carboxylase

Enzyme that catalyzes the conversion of CO2 to organic acids in C4 plants.

Electron transport system

Complex of proteins that transfer electrons to produce ATP.

Fermentation

Anaerobic process that converts glucose into energy without oxygen.

Aerobic respiration

Process that requires oxygen to release energy from glucose.

Anaerobic respiration

Process that occurs without oxygen to produce energy.

Citric Acid Cycle

Krebs cycle; a key metabolic pathway that generates energy through oxidation.

Chemiosmosis

Process by which ATP is produced in the mitochondria.

Glucose

Simple sugar that is a primary energy source for plants.

Ribulose bisphosphate (RuBP)

5-carbon sugar that combines with CO2 in the Calvin cycle.

Photosystem I

Complex that absorbs light and produces NADPH.

Photosystem II

Complex that absorbs light and produces ATP.

Carotenoids

Pigments that provide color and assist in photosynthesis.

NAD+

Oxidized form of NADH that acts as an electron carrier.

Aquatic Plants

Plants that may utilize alternative methods for carbon fixation.

Mesophyll cells

Cells in leaves where gas exchange occurs and photosynthesis takes place.

Light intensity

Amount of light available for photosynthesis.

Catalysts

Substances that speed up biochemical reactions without being consumed.

Chlorophyll a

Main pigment in photosynthesis that absorbs blue and red light.

Chlorophyll b

Accessory pigment that assists chlorophyll a in capturing light.

Reactants

Substances that undergo a chemical change during a reaction.

Products

Substances formed as a result of a chemical reaction.

Oxygen

Gas released as a by-product of photosynthesis.

Carbon Dioxide

Gas taken in by plants for photosynthesis.

Water

Required for photosynthesis; source of electrons.

Heat energy

Energy that may dissipate from excited electrons in pigments.

Transpiration

Process by which water vapor is lost from plants.

Glucose metabolism

Pathway of energy production via glucose breakdown.

Sulfate reduction

Process of converting sulfate to sulfide in some metabolic pathways.

Photosynthetic unit

Group of pigment molecules working together in photosynthesis.

Electron donor

Substance that donates electrons in oxidation-reduction reactions.

Photosynthesis efficiency

Measure of how effectively plants convert light energy into chemical energy.

Nitrogen fixation

Process of converting nitrogen gas into a biologically usable form.

Chemiosmotic phosphorylation

Mechanism of ATP generation using a proton gradient.

Respiratory substrates

Compounds, such as glucose, that are used in respiration.