Lecture Review on Macromolecules and Cell Biology

Midterm Information

  • Midterm grades are due on Friday, at the end of week four of an eight-week class.

  • The midterm will consist of two test grades, covering units one and two.

  • Adjustments may be made to course content to fit eight-week schedule due to previous disruptions (1 week off).

  • Past due assignments can still be submitted, but there may be a late penalty.

Technical Issues and Communication

  • Instructors encourage students to communicate if they experience technical difficulties.

  • Video quizzes available on various topics, such as proteins and nucleic acids, and results should be visible to the instructor.

  • Video quizzes automatically update in the Canvas system, which may cause delays.

  • Assignments due:

    • Scientific method (before chapter three)

    • Test for sugars and microscopic water (due Sunday)

    • Connect assignment for chapter three.

Current Week's Agenda

  • Focus this week on proteins, nucleic acids, and organelles.

  • Students will finish a specific sheet related to these topics.

  • Review of organelles and preparation for the upcoming Unit 2 test scheduled for Tuesday.

Upcoming Tests

  • Tests have been rescheduled; next test on Unit 3 after the Unit 2 test scheduled for Tuesday.

  • All tests will include study guide questions and practice tests.

  • Functional groups will be featured on tests, which will include: hydroxyl, carboxyl, amino, and phosphate.

Functional Groups

  • The matching section for the test will have functional groups and their corresponding structures.

  • Reactions associated with functional groups include:

    • Dehydration Reaction: Combines two monomers by removing water.

    • Hydrolysis Reaction: Breaks polymers apart by adding water.

    • Important for digestion processes in the body.

Proteins

  • Monomer: Amino acid, characterized by the amino functional group.

  • Structure of Amino Acids:

    • Central carbon, amino group, carboxyl group, and a variable R group.

    • 20 different amino acids exist, each with unique properties determined by their R groups.

  • Peptide Bonds: Form between amino acids to create proteins.

  • Types of proteins and their functions:

    • Antibodies (immune response)

    • Enzymes (catalysts for chemical reactions)

    • Motor proteins (muscle contraction, e.g., actin and myosin)

    • Transport proteins (movement across membranes).

  • Protein Structure:

    • Primary: Sequence of amino acids.

    • Secondary: Hydrogen bonding that shapes the structure into alpha helices or beta sheets.

    • Tertiary: Three-dimensional structure.

    • Quaternary: Structure involving more than one polypeptide chain.

Nucleic Acids

  • Function: Carry genetic information (DNA and RNA).

  • Monomer: Nucleotide

    • Components: phosphate group, sugar, nitrogenous base (Adenine, Cytosine, Guanine, Thymine, Uracil).

  • The relationship between nucleic acids and proteins is crucial for gene expression and cellular function.

Lipids

  • Categorized as fats, lipids encompass various classes of molecules:

    • Closest monomer: Fatty acid.

    • Triglycerides: Composed of three fatty acids and glycerol, used as an energy source.

    • Steroids: Important for cell communication, e.g., cholesterol, testosterone, and estrogen.

    • Waxes: Provide protection (e.g., plant leaves, skin).

  • Atoms in lipids typically include carbon, hydrogen, and oxygen.

  • Types:

    • Saturated Fats: Solid at room temperature, found in animal fats.

    • Unsaturated Fats: Liquid at room temperature, found in plant oils.

    • Trans Fats: Artificially created, associated with health risks.

Cell Theory

  • States:

    1. The cell is the smallest unit of life.

    2. All living things are composed of cells.

    3. Cells arise from other cells.

  • All cells share common features:

    • Genetic material, ribosomes, cytoplasm, and cell membrane.

Prokaryotes vs. Eukaryotes

  • Prokaryotic Cells: Smaller, simpler, lack membrane-bound organelles, e.g., bacteria.

    • Nucleoid region contains their genetic material.

  • Eukaryotic Cells: Larger, complex, contain a nucleus and membrane-bound organelles.

    • Organelles include:

    • Nucleus (control center for cell function).

    • Ribosomes (protein synthesis).

    • Endoplasmic Reticulum (rough for protein synthesis, smooth for lipid synthesis).

    • Golgi Apparatus (protein processing and shipping).

    • Lysosomes (digestion of macromolecules).

    • Mitochondria (energy production), inherited maternally.

    • Chloroplasts (in plants, for photosynthesis).

Endomembrane System

  • Flow of proteins from nucleus to ribosome to rough endoplasmic reticulum, Golgi apparatus, and potentially to lysosomes or the cell membrane.

  • Vesicles transport proteins between organelles.