Metabolic Processes Flashcards
(19 cards)
What is Cellular Respiration?
A catabolic process that breaks down glucose to produce ATP (energy). It occurs in most eukaryotic cells and includes glycolysis, pyruvate oxidation, Krebs cycle, and oxidative phosphorylation.
What is Photosynthesis?
An anabolic process in plants, algae, and some bacteria that converts light energy into chemical energy stored in glucose. It includes the light-dependent reactions and light-independent reactions (Calvin cycle).
Cellular Respiration Breakdown Reactants:
Glucose (C₆H₁₂O₆)
Oxygen (O₂)
Cellular Respiration Breakdown Products:
Carbon dioxide (CO₂)
Water (H₂O)
Energy (ATP)
Cellular Respiration Breakdown Stages:
Glycolysis, Pyruvate Oxidation, Krebs Cycle, Oxidative Phosphorylation
Glycolysis
Location: Cytoplasm
Reactants: Glucose
Products: 2 Pyruvate, 2 ATP (net), 2 NADH
Conditions: Anaerobic (doesn’t need O₂)
Pyruvate Oxidation
Location: Mitochondrial matrix
Reactants: 2 Pyruvate
Products: 2 Acetyl-CoA, 2 CO₂, 2 NADH
Conditions: Aerobic
Krebs Cycle (Citric Acid Cycle)
Location: Mitochondrial matrix
Reactants: 2 Acetyl-CoA
Products: 4 CO₂, 2 ATP, 6 NADH, 2 FADH₂
Conditions: Aerobic
Oxidative Phosphorylation (ETC & Chemiosmosis)
Location: Inner mitochondrial membrane
Reactants: NADH, FADH₂, O₂
Products: ~28–34 ATP, H₂O
Conditions: Requires oxygen
What is Fermentation?
Fermentation is a process that happens when there’s little or no oxygen. It helps keep glycolysis going by turning NADH back into NAD⁺, which is needed to keep making a small amount of energy (ATP).
Lactic Acid Fermentation (where, who, products)
- Cytoplasm of muscle cells (humans), bacteria
- Animals (during intense exercise), lactic acid bacteria
- 2 ATP, lactic acid
Alcoholic Fermentation (where, who, products)
- Cytoplasm
- Yeast, some bacteria
- 2 ATP, ethanol, CO₂
What are stomata?
Stomata are pores in plant leaves controlled by guard cells.
Functions of Stomata
- Allow CO₂ to enter for photosynthesis
- Release O₂ (by-product of photosynthesis)
- Control water loss (transpiration)
- They also close during drought to conserve water, which also limits photosynthesis due to less CO₂ entering.
Aerobic Respiration
Oxygen = Required
ATP yeild = High (~36–38 ATP)
End products = CO₂ , H₂O
Location = Mitochondria & cytoplasm
Organisms = Most plants, animals, fungi
Anaerobic Respiration/Fermentation
Oxygen = Not required
ATP yeild = Low (~2 ATP)
End products = Lactic acid or ethanol + CO₂
Location = Cytoplasm only
Organisms = Some bacteria, yeast, muscle cells
Light-Dependent Reactions
Location: Thylakoid membrane
Reactants: H₂O, light, NADP⁺, ADP
Products: O₂ , ATP, NADPH
Key Processes: Electron Transport Chain, Chemiosmosis, Photolysis (splitting water)
Light-Independent Reactions (Calvin Cycle)
Location: Stroma of the chloroplast
Reactants: CO₂, ATP, NADPH
Products: Glucose (C₆H₁₂O₆), ADP, NADP⁺
Doesn’t require light directly, but depends on ATP/NADPH from light reactions
Chemiosmosis (in Light and Light-Independent Reactions)
- H⁺ ions move through ATP synthase to generate ATP
- Driven by proton gradient across the membrane
