Key Concepts of AP Biology Unit 1

Sep 16, 2024

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.