Biochemistry Key Concepts: Definitions and Terminology
Biochemistry Key Concepts
Lesson 1, 2, and 3:
- Hydrolysis reaction: The cleavage of an element by the addition of the elements of water.
- Amphipathic compounds: Molecules with both polar and nonpolar regions.
- Hydrophobic molecules: Molecules that are not dissolved in water.
- Condensation reaction: The formation of cellular polymers from their subunits by simple reversal of hydrolysis.
- Functional groups: Added groups that confer specific chemical properties on the molecule.
- pH scale: It is a convenient means
Glycolysis and the Krebs Cycle: A Detailed Breakdown
Glycolysis
Glycolysis is the first step in cellular respiration. It is the process of breaking down glucose to make pyruvate. Glycolysis does not require oxygen (O2) and occurs in the cytosol.
Aerobic Respiration (Presence of Oxygen)
- Glycolysis
- Pyruvate oxidation, Krebs cycle
- Electron transport chain (ETC), oxidative phosphorylation
Anaerobic Respiration (Absence of Oxygen)
- Glycolysis
- Alcoholic fermentation (yeast)
- Lactic acid fermentation
Glycolysis Summary
- Glucose is broken down into 2 pyruvate molecules.
Water Resources Management in Disaster Areas: 2008 EES Summer School
EES Summer School: Ecological Management of Disaster Areas 2008
Water Resources Management
Questions:
1. What is the Hydrological Cycle and How Can Water Balance Be Quantified?
Caused by solar energy.
C: ocean → evaporation → precipitation → runoff (→ evaporation) → infiltration (→ ocean) → subsurface runoff → ocean
Annual Water Balance in the World:
Quantification: Precipitation (P) = Evapotranspiration (E) + Runoff (R)
520 (km3) = 484 + 36
Some Points:
- Water moves from one reservoir to another
Krebs Cycle and Glycolysis: Steps and Enzymes
Krebs Cycle (Citric Acid Cycle)
Step 1: Formation of Citrate
- Substrate: Acetyl CoA
- Enzyme: Citrate synthase
- Cofactor: None
- Product: Citrate
Step 2: Isomerization of Citrate
- Substrate: Citrate
- Enzyme: Aconitase
- Cofactor: None
- Product: Isocitrate
Step 3: Oxidative Decarboxylation of Isocitrate
- Substrate: Isocitrate
- Enzyme: Isocitrate dehydrogenase
- Cofactor: NAD+
- Product: Alpha-ketoglutarate, NADH, CO2
Step 4: Oxidative Decarboxylation of Alpha-ketoglutarate
- Substrate: Alpha-ketoglutarate
- Enzyme: Alpha-ketoglutarate
TCA Cycle: A Key Metabolic Pathway in Cellular Respiration
The Tricarboxylic Acid (TCA) Cycle
The Tricarboxylic Acid (TCA) cycle, also known as the citric acid cycle or Krebs cycle, is a central metabolic pathway that plays a crucial role in the aerobic respiration of eukaryotic cells and many bacteria. It is named after Sir Hans Krebs, who elucidated its key features in the 1930s and 1940s. The TCA cycle takes place in the mitochondria of eukaryotic cells and the cytoplasm of prokaryotic cells.
Detailed Description of the TCA Cycle
- Acetyl-CoA Entry:
- The TCA
Cellular Respiration: Glycolysis, Krebs Cycle, and More
Glycolysis
Glycolysis (ATP Expenditure)
- Phosphorylation: Glucose + ATP – (Hexokinase) -> ADP + Glucose-6-Phosphate
- Glucose-6-Phosphate <- (Phosphohexose Isomerase) -> Fructose-6-Phosphate
- Phosphorylation: Fructose-6-Phosphate + ATP – (Phosphofructokinase-1) -> Fructose-1,6-Bisphosphate + ADP
- Fructose-1,6-Bisphosphate <- (Aldolase) -> Glyceraldehyde-3-Phosphate + Dihydroxyacetone Phosphate
- Dihydroxyacetone Phosphate <- (Triose Phosphate Isomerase) -> Glyceraldehyde-3-Phosphate
Energy
Read More