1.1 Basic Biology Review

Amino Acids & Proteins

AA structure

• Central carbon surrounded by an amino group (H2N), a Carboxylic acid group (O=C-OH), an H, and a unique side chain

• r -group

• Methyl groups

AA Types

• Humans use about 20 AAs

• Essential, conditionally essential, Nonessential

Steps of Protein synthesis

• Transcription - genes are copied into mRNA

  • mRNA built by RNA polymerase

  • mRNA leaves nucleus and goes to ribosome

• Translation - mRNA turned into a protein

  • each codon of three bases codes for a specific AA

  • tRNA caries an amino acid and matches the anti-codon of three bases with the mRNA

  • Peptide bonds - bind AAs together to form proteins

  • ribosome moves along the mRNA until a complete chain of AAs is formed

  • chain of AAs folds up to form protein

Cellular Respiration (Aerobic)

Glycolysis

• glucose is converted into pyruvate

• Net yield +2 ATP

• pyruvate converted to acetyl CoA

Krebs Cycle / Citric acid

• CO2 & +2ATP

• Acetyl CoA broken down further into citric acid

• Citric acid is oxidized and energy is used to bind ADP and phosphate to make ATP and electron carriers (NADH & FADH2)

Electron Transport Chain

• electrons used to create proton gradient to pump protons across membrane

• Chemiosmosis - ATP synthase enzyme creates ATP

• +34 ATP

Other

• Proteolysis - the process by which proteins are broken down by HCL, pepsin & other digestive enzymes