AP Biology Unit 1 Review

Introduction

• AP Bio is a complex course requiring mastery of numerous topics.
• Key topics for Unit 1:
  • Chemistry of water and hydrogen bonding
  • Carbon, elements of life, and functional groups
  • Monomers and polymers
  • Four major biological molecules: carbohydrates, lipids, proteins, nucleic acids.

Chemistry of Water and Hydrogen Bonding

• Hydrogen Bonding

  • Water is a polar molecule due to unequal electron sharing between oxygen and hydrogen.
  • Hydrogen bonds form between molecules, not within them.
  • Essential in DNA, RNA, proteins.

• Properties of Water

  • Cohesion: Hydrogen bonds between water molecules, responsible for high heat of vaporization, specific heat, and surface tension.
  • Adhesion: Water sticking to other substances (e.g., plant xylem).
  • Surface Tension: Water molecules create a net that can support small objects.

• pH and Ion Concentration

  • Acids have more hydrogen ions; bases have more hydroxide ions.
  • Important for understanding biological processes.

Elements of Life

• CHNOPS: Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur.
• Carbon is central to biological molecules.
• Phosphorus is key in ATP.

Monomers and Polymers

• Monomers and Polymers

  • Biomolecules (carbohydrates, proteins, nucleic acids) built from monomers.
  • Monomer example: glucose.

• Dehydration Synthesis and Hydrolysis

  • Dehydration synthesis combines monomers by removing water.
  • Hydrolysis breaks polymers by adding water.

Functional Groups

• Important Functional Groups
  • Phosphate groups (energy exchange in ATP)
  • Methyl groups (silence DNA)
  • Hydroxyl, Carbonyl (polarity)
  • Carboxyl, Amino (essential in amino acids)
  • Sulfhydryl (protein structure)
  • Acetyl (activates DNA)

Carbohydrates and Lipids

• Carbohydrates

  • Monosaccharides like glucose are energy sources.
  • Polysaccharides: Starch (energy), Cellulose (structure).

• Lipids

  • Nonpolar, hydrophobic molecules.
  • Functions: energy storage, waterproofing, membrane structure.

Proteins

• Structure of Proteins

  • Monomer: amino acid, includes amine group, carboxyl group, R group.
  • Four levels of structure: Primary (sequence), Secondary (alpha helix, beta sheet), Tertiary (R group interactions), Quaternary (multiple polypeptides).

• Example: Hemoglobin

  • Quaternary structure, key to oxygen transport.
  • Sickle cell disease caused by a mutation altering protein properties.

Nucleic Acids

• Importance

  • DNA/RNA are genetic material carriers.
  • DNA: hereditary material, RNA: involved in protein synthesis.

• Structure

  • Monomers: nucleotides (sugar, phosphate, nitrogenous base).
  • DNA bases: adenine, thymine, cytosine, guanine.
  • RNA bases: adenine, uracil, cytosine, guanine.
  • DNA is anti-parallel, with hydrogen bonds between bases (A-T, C-G).

• ATP

  • Nucleotide monomer, crucial for cellular energy.

Conclusion

• Comprehensive understanding of these topics is crucial for success in AP Biology exams.
• Learn-Biology.com offers resources to aid in study and exam preparation.