Exam 4 and Final Exam Review

Exam Review Overview

  • Exam 4 and Final Exam Review

  • Course: BSC 2010

  • Instructor: Marks

Schedule

  • Final Review Units:

    • Unit 1

    • Unit 2

    • Unit 3

  • Exam 4 Review:

    • Unit 4

Chapter 2: Chemical Context of Life

  • Focus on 3 questions related to the content.

Atomic Structure

  • Atomic Mass = # of neutrons + # of protons

    • Measured in atomic mass units (amu)

  • Atomic Number = # of protons

    • Protons define the element.

      • Example: an atom with 1 proton is hydrogen.

Subatomic Particles

  • Particles within an atom:

    • Electron:

      • Mass = ~0, Charge = -1, Location = orbitals.

    • Proton:

      • Mass = 1 amu, Charge = +1, Location = nucleus.

    • Neutron:

      • Mass = 1 amu, Charge = 0, Location = nucleus.

Electrons

  • Arrangement:

    • Electrons occupy shells/orbitals around the nucleus

    • First shell: 2 electrons; subsequent shells: 8 electrons.

  • Valence Electrons:

    • Electrons in the outer shells determine bonding capabilities.

    • Can form single, double, or triple bonds with other atoms' valence electrons.

Bonds

  • Covalent Bonds: Non-metal + Non-metal

    • Electrons are shared between atoms.

    • Atoms may have differing electronegativities leading to polarity.

  • Polar Bonds:

    • Electrons are attracted more to one atom (H-N, H-O-H).

  • Nonpolar Bonds:

    • Electrons are shared equally (C-H, H-H).

Hydrogen Bonds

  • Definition:

    • Interactions occur between the partial negative charge of oxygen and the partial positive charge of hydrogen in polar covalent bonds in water.

Chapter 3: Water and Life

  • Addressed in 4 questions related to water's properties and behavior.

Properties of Hydrogen Bonds

  • Heat Capacity:

    • Hydrogen bonds grant water its capacity to resist temperature changes.

    • More heat is necessary to break these bonds and change temperature.

Polarity in Solutions

  • Dissolution:

    • Polar substances dissolve in polar solvents due to partial charge interactions.

    • Nonpolar molecules do not dissolve in polar solutions.

Molarity and Molar Mass

  • Molarity (M):

    • M = mol/L

  • Molar Mass:

    • Measurement in g/mol.

    • Conversion between moles, molarity, and molar mass.

    • Use logic to verify calculations.

Acids and Bases

  • Acids: Donate protons (H+).

    • pH decreases (1-6 range).

  • Bases: Accept protons (H+).

    • pH increases (8-14 range).

  • Water Ionization:

    • In water: [H+][OH-]= 14.

Chapter 4: Carbon and the Molecular Diversity of Life

  • Cover 3 questions related to carbon's properties and versatility in biomolecules.

The Carbon Atom

  • Valence Electrons:

    • 4 unpaired electrons allow for complex bonding and molecular diversity.

Hydrocarbons

  • Composed solely of H and C.

  • Hydrocarbons are nonpolar and do not mix with polar water.

Functional Groups

  • Hydroxyl: ( -OH) Polar.

  • Methyl: (R-CH3) Nonpolar.

  • Carbonyl: (R-C=O) Polar.

  • Carboxyl: (R-COOH) Acidic, releases H+.

  • Amino: (R-NH2) Basic, accepts protons.

  • Phosphate: (R-PO4) Acidic.

  • Sulfhydryl: (R-SH) Polar.

Chapter 5: Structure and Function of Large Biological Macromolecules

  • Focused on 4 questions surrounding macromolecule functions.

Polymers

  • Monomer: Single unit.

  • Polymer: Multiple linked monomers.

  • Synthesis and Breakdown:

    • Dehydration Synthesis: Removes water to link monomers.

    • Hydrolysis: Adds water to break bonds.

Lipids

  • Characteristics:

    • Do not form polymers, consist of long, nonpolar hydrocarbons.

    • Includes fatty acids (hydrocarbon + carboxyl).

    • Phospholipids: Amphipathic traits due to polar heads and nonpolar tails.

Carbohydrates

  • Composed of C, H, O; typically in ring formation.

  • Can form polysaccharides due to glycosidic linkages.

Proteins

  • Made of amino acids and form polypeptides.

  • Amino acids categorized by R-groups.

Nucleic Acids

  • Composed of nucleotides with phosphate, sugar, and nitrogenous bases.

Chapter 7: Membrane Structure and Function

  • Addressed in 5 questions regarding cellular membranes.

Cell Membranes

  • Plasma Membrane: Phospholipid bilayer; semi-permeable.

  • Permeability:

    • Nonpolar: passes easily (O2, CO2).

    • Polar: passes slowly (water).

    • Charged: cannot pass (ions).

Tonicity

  • Water Movement:

    • High concentration attracts water; solutes diffuse to lower concentration.

  • Types:

    • Hypertonic: cell shrinks.

    • Isotonic: normal cell shape.

    • Hypotonic: cell swells.

Active and Passive Transport

  • Passive Transport: No energy required (Diffusion, Facilitated diffusion).

  • Active Transport: Energy required to move substances against gradient (sodium-potassium pump).

Chapter 8: Intro to Metabolism

  • Planned for 4 questions on metabolism pathways.

Pathways

  • Catabolic Pathways: Release energy by breaking down molecules.

  • Anabolic Pathways: Consume energy to build molecules.

Chapter 9: Cellular Respiration and Fermentation

  • Look at 7 questions on respiration processes.

Redox Reactions

  • Oxidation: Loss of electrons (reducing agent).

  • Reduction: Gain of electrons (oxidizing agent).

Glycolysis

  • Splits glucose into pyruvate; has energy investment and payout phases.

Citric Acid Cycle

  • Completes pyruvate breakdown; produces ATP, NADH, and FADH2.

  • Total per glucose: 2 ATP, 6 NADH, 2 FADH2.

Oxidative Phosphorylation

  • Electron Transport Chain: Moves electrons from NADH and FADH2.

  • Chemiosmosis: H+ ions move through ATP synthase to generate ATP.

Chapter 10: Photosynthesis

  • Questions surrounding photosynthetic processes.

Light Reactions

  • Goals: Split H2O, release O2, generate ATP/NADPH.

  • Steps involving photosystem II & I; energy transformation occurs.

Calvin Cycle

  • Occurs in the stroma, inputs CO2, ATP, and NADPH; outputs include ADP, NADP+, G3P.

Cancer and Gene Regulation

  • Focus on regulation mechanisms across cellular growth and differentiation.

Gene Regulation

  • Allows cells to express different genes based on their function.

Cancerous Cells

  • Malfunction in gene regulation leads to cancer.

  • Oncogenes: Promote cell division.

  • Tumor suppressor genes: Inhibit cell division.

Cellular Differentiation

  • Early development relies on cytoplasmic determinants in embryos.

Eukaryotic Gene Expression Regulation

  • Factors include histones and modifications that affect accessibility of the gene.

Operons

  • Groups of genes regulated as a unit, controlled by a single promoter.

  • Repressor Proteins: Turn off operons.