General Biology 110: Comprehensive Science Section Review

Page 1: Introduction to General Biology 110

This section, led by Dr. Moayad, focuses on assessing student understanding of fundamental biological concepts through a series of review questions.

Page 2: Cell Structures and Basic Metabolism

  • Plant Cells: Identified by the presence of a cell wall and chloroplasts.
  • Cellular Respiration: The process of acquiring energy by breaking down organic molecules.
  • Plasma Membrane: Primarily functions in regulating the entrance and exit of substances.
  • Bacterial Cells: Characterized by lacking a nucleus, though they contain cytoplasm, ribosomes, and flagella.

Page 3: Organelle Specialization and Initial Metabolic Steps

  • Smooth Endoplasmic Reticulum (ER): Responsible for lipid production.
  • Golgi Apparatus: Modifies molecules and adds carbohydrate chains to proteins to form glycoproteins.
  • Ribosomes: Perform protein synthesis.
  • Glycolysis: The first step of cellular respiration; it takes place in the cytoplasm (outside the mitochondria).

Page 4: Photosynthesis and Respiration Products

  • Glycolysis Result: Produces two pyruvate molecules (pyruvic acid).
  • Photosynthesis Stages: Solar energy is absorbed during the light reaction, while CO2CO_2 is absorbed during the Calvin cycle.
  • Final Products:   - Cellular Respiration: ATPATP, CO2CO_2, and water.   - Photosynthesis: Glucose and oxygen (O2O_2).
  • Vacuoles: Organelles containing powerful digestive enzymes (specifically in plant cells).

Page 5: Cell Differentiation and Membrane Composition

  • Rough ER: Distinguished by attached ribosomes.
  • Prokaryotes vs. Eukaryotes: The presence of a nucleus is the primary distinction.
  • Plant vs. Animal Cells: Distinguished by the cell wall.
  • Plasma Membrane Structure: Composed of a phospholipid bilayer and embedded proteins. Phospholipids are amphipathic, containing both hydrophilic and hydrophobic regions.

Page 6: Membrane Transport Mechanisms

  • Fluid Model: The membrane is considered fluid due to its lipid components.
  • Aquaporins: Specialized channel proteins for water transport.
  • Active Transport: Requires energy to move substances, unlike passive transport or osmosis.
  • Isotonic Solution: Concentrations of solute are equal inside and outside the cell.
  • Bulk Transport: Endocytosis and exocytosis move very large molecules into or out of the cell.

Page 7: Movement and Concentration Gradients

  • Exocytosis: Substance exit; Endocytosis: Substance entry.
  • Passive Transport: Movement (like diffusion and osmosis) that does not require energy.
  • Active Transport: Movement from lower to higher concentration (against the gradient), such as the sodium-potassium pump in nerve cells.
  • Osmosis: Specifically defined as the diffusion of water.

Page 8: Specialized Proteins and Solution Effects

  • Channel Proteins: Allow ions/molecules to cross reaching the inner mitochondrial membrane or plasma membrane.
  • Carrier Proteins: Assist in transporting ions like sodium and potassium across the membrane.
  • Phagocytosis: A process where the cell engulfs viruses or food particles.
  • Hypotonic Solution: Causes cells to intake water and swell.

Page 9: Viral Reproduction and Cycles

  • Virus Characteristics: Contain either DNA or RNA and replicate only inside a host cell.
  • Lytic Cycle: Reproductive cycle that destroys the host cell.
  • Lysogenic Cycle: The viral genome integrates into the host DNA.
  • Isotonic State: Water does not move in or out of the cell.

Page 10: Bacterial Classification and Exchange

  • Taxonomy: Bacteria are prokaryotes; protists are eukaryotes.
  • Genetic Exchange:   - Conjugation: Via a pilus filament.   - Transduction: Via bacteriophages.
  • Tobacco Mosaic Virus (TMV): Cannot infect humans due to differences in human cell receptors.
  • Flagella: Used for movement in bacteria.

Page 11: Bacteria, Archaea, and Viral Defense

  • Gram Staining: Gram-positive bacteria appear purple; Gram-negative appear pink.
  • Viral Defense: Bacteria use restriction enzymes to cut foreign phage DNA.
  • Archaea: Extremophiles that survive harsh conditions due to unusual lipids in their plasma membrane.

Page 12: Microbiology Fundamentals

  • Prophage: Viral genome integrated with bacterial DNA.
  • Classification: Viruses are categorized by nucleic acids and outer envelopes.
  • Binary Fission: The method of bacterial asexual reproduction.
  • Viral Structure: Consists of a protein coat (capsid) and nucleic acids.

Page 13: Fungal Anatomy and Physiology

  • Fungi Characteristics:   - Multicellular body called a mycelium.   - Network of filament tissue called hyphae.   - Cell walls containing chitin.   - Energy stored as glycogen.
  • Phylogeny: Bacteria and Archaea are both prokaryotes.

Page 14: Fungal and Protist Lifestyles

  • Fungal Nutrition: Occurs through absorption (heterotrophic).
  • Reproduction: Both sexual and asexual; fragmentation is a common asexual method.
  • Protists: Examples include diatoms; many protozoans ingest food via endocytosis.

Page 15: Specialized Reproductive Methods

  • Yeast: Unicellular fungi that reproduce asexually via budding.
  • Fungal Spores: The primary means of reproduction for many fungi.
  • Mosaic Model: The plasma membrane is considered mosaic due to its protein components.

Page 16: Plasma Membrane Interactions

  • Diffusion: Oxygen may pass the membrane via simple diffusion.
  • Hypertonic Solution: Outside concentration is higher than inside, causing cells to shrink.
  • Receptor Proteins: Bind specific molecules to trigger cellular responses.
  • Lysosomes/Vacuoles: Plant vacuoles and animal lysosomes contain digestive enzymes for recycling non-functional organelles.

Page 17: Viral and Bacterial Structures

  • Lytic Cycle Steps: Attachment, Penetration, Biosynthesis, Assembly, and Release.
  • Bacterial Envelope Layers (Inside to Outside): Plasma membrane ightarrow Cell wall ightarrow Glycocalyx.

Page 18: Cellular Internal Components

  • Nucleoid: The region where the bacterial chromosome is located.
  • Rough ER: Functions in adding carbohydrate chains to proteins.
  • Endocytosis: The specific term for large molecules entering the cell.

Page 19: Pro- and Eukaryotic Distinctions

  • Plasmid: Extra-chromosomal circular supercoiled DNA in bacteria.
  • Nucleus: Only present in eukaryotic cells; absent in prokaryotes (Bacteria and Archaea).
  • High External Concentration: Termed a hypertonic solution.

Page 20: Molecular Biology and Respiration Sequences

  • Phospholipids: Hydrophilic head and hydrophobic tail.
  • Cellular Respiration Sequence: Glycolysis ightarrow Preparatory reaction ightarrow Citric acid cycle ightarrow Electron transport chain.
  • Polymerase: Enzyme required to produce viral DNA/RNA.

Page 21: Enzymes and Cell Solutions

  • Peroxisomes: Contain the enzyme catalase.
  • Cell Recognition Protein: Helps the body identify invading pathogens.
  • Cytolysis: Occurs in a hypotonic solution as the cell swells and bursts.
  • Heterotrophic Bacteria: Beneficial for breaking down organic molecules.

Page 22: Transport and Model Review

  • Facilitated Diffusion: A type of transport that does not require energy.
  • Fluid Mosaic Model: Describes the plasma membrane structure.
  • Pinocytosis: A specific type of endocytosis for liquid uptake.

Page 23: Proteins and Permeability

  • ATP Production: The Electron transport chain phase produces the most ATPATP.
  • Membrane Permeability: Small, non-charged molecules cross the plasma membrane most quickly.
  • Aquaporin: The specific channel protein for water movement.
  • Golgi Apparatus: Crucial for modifying and packaging proteins for secretion.

Page 24: Blood Groups and Membrane Selectivity

  • Blood Groups: Human A,B,OA, B, O blood groups are based on carbohydrate chains in the plasma membrane.
  • Selectively Permeable: Describes a membrane that allows only certain substances to pass.
  • Naked Virus: A virus that lacks an outer envelope.

Page 25: Bacterial and Fungal Components

  • Peptidoglycan: The molecule that strengthens the bacterial cell wall.
  • Glycocalyx: A polysaccharide layer outside the bacterial cell wall (capsule).
  • Simple Diffusion: Molecules like oxygen cross the membrane this way.

Page 26-29: Final Summaries

  • Capsid: The protein coat of a virus.
  • Lysosomes: Contain powerful digestive enzymes in animal cells.
  • Bacterial Reproduction: Primarily asexual through binary fission.
  • Protists: All protists are eukaryotes.
  • Bacterial Cell Wall: Functions Primarily to maintain the cell's shape.
  • Photosynthesis Start: Begins with the light reaction.