Week 9 SG

W9.1 - Cell-Cell Interactions and Chemical Signals in Animals

• Learning Outcome: Understand the differences between the extracellular matrix (ECM) of animal cells and plant cell walls.
  • Functions of Extracellular Regions:
  • Communicate environmental signals to the cell.
  • Serve protective functions.
  • Comparative Analysis:
  • Growing vs Mature Plant Cells:
    • Investigate how cell wall properties relate to function.
  • Types of Animal Cells:
    • Compare different ECM properties and their functional roles.

Chapter 11 - Cell Connectivity and Communication

Section 11.2: Adjacent Cells Connect and Communicate

• Key Terms:
  • Epithelium/Epithelia: Tissues forming protective barriers.
  • Tight Junctions: Seal adjacent cells together, preventing leakage.
  • Desmosomes: Anchoring junctions providing mechanical strength.
  • Cell Adhesion Proteins: Involved in homotypic interactions.
  • Gap Junctions: Allow direct communication between adjacent animal cells.
  • Plasmodesmata: Channels for communication between plant cells.
• Learning Outcome: Differentiate the functions of tight junctions, desmosomes, gap junctions, and plasmodesmata.
  • Considerations:
  • Type of association (tight vs loose) between cells.
  • Types of information communicated.

Section 11.3: Distant Cell Communication

• Key Terms:
  • Signaling Molecules:
    • Lipid soluble vs lipid insoluble.
  • Hormones: Chemical messengers.
  • Signal Receptor: Molecule that receives signals.
  • Signal Transduction: Process of converting a signal into a cellular response.
  • Signal Amplification: Magnifying the signal's effect.
  • Second Messenger: Molecules that mediate signaling pathways following receptor activation.
  • Phosphorylation Cascade: Chain of events where one protein kinase activates another.
  • Kinases and Phosphatases: Enzymes that add or remove phosphate groups, respectively.
  • Signal Response: Outcome of the signaling process.
  • Loss of Function vs Gain of Function: Understanding mutations in signaling pathways.
• Learning Outcome: Diagram a signaling transduction mechanism and predict outcomes from network perturbations.
  • Key Questions:
  • How external signals become internal cell responses?
  • Mechanisms involved (e.g., enzyme activities, transcription regulation).

Chapter 46 - Chemical Signals in Animals

Section 46.1: Cell-to-Cell Signaling Overview

• Key Terms:
  • Autocrine: Signals affect the issuing cells themselves.
  • Paracrine: Signals affect nearby cells.
  • Endocrine: Hormonal signals that travel long distances in the bloodstream.
  • Homeostasis: Maintaining stable internal conditions.
  • Feedback Mechanisms: Negative vs positive feedback in physiological systems.
• Learning Outcome: Describe autocrine, paracrine, and endocrine signaling types.

W9.2 - The Cell Cycle and Control of Gene Expression in Eukaryotes

• Main Focus: Understanding repercussions of uncontrolled cell division leading to cancer.

Readings and Key Concepts

• Ch 12 - The Cell Cycle:
  • M-phase Promoting Factor (MPF): Initiates cell division.
  • Cyclins: Regulatory proteins involved in cell cycle control.
  • Cell Cycle Checkpoints: G1, G2, and M-phase check the integrity before proceeding.
  • Apoptosis: Programmed cell death.
  • Tumors: Understanding benign vs malignant.

Concepts Related to Cancer

• Angiogenesis and Metastasis: Cancer cells stimulate blood vessel growth to spread.
• Growth Factors: Their roles in cancerous development.
• Learning Outcomes for Cell Cycle Control:
  • Explain cell cycle checkpoints.

Gene Regulation and Cancer

• Ch 19 - Gene Expression Control:
  • Oncogenes: Mutated genes promoting cancer in gain-of-function scenarios.
  • Tumor Suppressors: Genes that prevent unchecked cell division.
• Learning Outcomes:
  • Predict outcomes based on gene classifications and scenarios.