Cell Biology Foundations: Syllabus, Course Structure, and Introduction to Cells

Course Overview

This course, Cell and Molecular Biology (BIOL 329), provides a comprehensive introduction to the structure, function, and evolution of cells. It covers foundational concepts in cell biology, including the origin of life, cellular metabolism, cell structure, and the diversity of cell types in both prokaryotic and eukaryotic organisms. The course also emphasizes the importance of cell biology in medicine, biotechnology, and research.

Course Structure and Grading

Grading Scale

Grade	Points	Percentage
A	810-900	90-100%
B	720-809	80-89%
C	630-719	70-79%
D	540-629	60-69%
F	0-539	Below 60%

Points Breakdown

Category	Points	Details
Weekly Assignments	110	11 assignments × 10 points each. Lowest 1 score dropped.
iClicker Questions	110	Capped at 110 points. 5 points per class. 80% participation, 20% correctness.
Panopto Questions (Lecture Recordings)	20	Points earned for answering embedded questions from lecture videos.
Quizzes	60	4 quizzes × 20 points each. Lowest score dropped.
Exams	600	4 exams × 150 points each. 50 questions, 3 points per question, all multiple choice. Optional comprehensive final offered.
TOTAL POINTS	900

Course Schedule (Selected Topics)

• Introduction to Cells and Cell Research

• Chemical Basis of Life

• Genes and Genomes

• DNA Replication, Maintenance, and Repair

• RNA Synthesis and Processing

• Protein Synthesis and Regulation

• Endoplasmic Reticulum, Golgi Apparatus, and Lysosomes

• Mitochondria and Chloroplasts

• Cytoskeleton and Cell Movement

• Cell Signaling

• Cell Cycle, Renewal, and Death

• Cancer

Introduction to Cells and Cell Research

Learning Objectives

• Explain how the first cell originated.

• Describe the major steps in the evolution of metabolism.

• Illustrate the structures of eukaryotic and prokaryotic cells.

• Outline the evolution of eukaryotic cells and multicellular organisms.

Why Study Cell Biology?

Cell biology is fundamental to understanding life and has broad applications in medicine and research.

• Medical advances: Genome editing, gene identification for diseases, targeted cancer therapies, designer drugs, and stem cell therapies.

• Fundamental principle: Understanding how cells work is key to understanding life itself.

Unity and Diversity of Cells

Unity

• All cells use DNA as genetic material.

• All cells have plasma membranes.

• All cells share basic energy metabolism mechanisms and a common genetic code.

Diversity

• Single-celled organisms (e.g., Bacteria, Amoeba, Yeasts).

• Multicellular organisms (e.g., humans with 200+ cell types).

• Specialized functions (e.g., memory, sight, movement, digestion).

Origin of Life Timeline

• 3.8 billion years ago: First life emerged.

• Primitive Earth's atmosphere: Little to no free oxygen, mainly CO2 and N2, reducing conditions favorable for organic molecule formation.

Miller-Urey Experiment (1950s)

• Simulated primitive Earth conditions with electric sparks and a mixture of H2, CH4, NH3, and water.

• Resulted in spontaneous formation of amino acids, demonstrating that organic molecules could form under early Earth conditions.

The RNA World Hypothesis

RNA is hypothesized to be the first self-replicating biomolecule due to its ability to serve as a template, catalyze reactions, and enable base pairing.

• Evolution progression: RNA → RNA + amino acids (genetic code) → DNA replaces RNA as genetic material.

The First Cell

• Key components: Self-replicating RNA and a phospholipid membrane enclosure.

• Phospholipids are amphipathic molecules that spontaneously form bilayers, creating a stable barrier between internal and external environments.

Evolution of Metabolism

Stage 1: Glycolysis (Anaerobic)

• First energy-generating reaction: Breakdown of glucose to pyruvate.

• Energy yield: 2 ATP molecules, no oxygen required.

Stage 2: Photosynthesis

• Harnesses energy from sunlight, converts CO2 to organic compounds.

• Critical by-product: Free O2 released into the atmosphere.

Stage 3: Oxidative Metabolism

• Uses O2 for complete glucose breakdown: $\text{Glucose} + O_2 \rightarrow CO_2 + H_2O$

• Energy yield: 36-38 ATP molecules (18-19 times more efficient than glycolysis).

Prokaryotes vs. Eukaryotes

Prokaryotes

• Two domains: Archaea (extremophiles) and Bacteria (common prokaryotes).

• No membrane-bound nucleus, smaller and simpler than eukaryotes.

• Genome: 0.6-5 million base pairs, diameter: 1-10 μm.

Eukaryotes

• Contain a nucleus (5-20 μm diameter) with linear DNA molecules.

• Multiple membrane-bound organelles, often 1,000x greater volume than prokaryotes.

Comparison Table: Prokaryotic vs. Eukaryotic Cells

Feature	Prokaryote	Eukaryote
Nucleus	Absent	Present
Cell diameter	~1 μm	10-100 μm
Organelles	Absent	Present
DNA content	1-5 million bp	15 million - 5 billion bp
Chromosomes	Single circular	Multiple linear

Major Eukaryotic Organelles

Energy Metabolism

• Mitochondria: Site of oxidative metabolism and ATP production; found in almost all eukaryotic cells.

• Chloroplasts: Site of photosynthesis; found only in plants and green algae.

Metabolic Compartments

• Lysosomes: Digestion of macromolecules.

• Peroxisomes: Various oxidative reactions.

• Vacuoles (plants): Digestion and storage of waste products and nutrients.

Summary

• Life originated 3.8 billion years ago with self-replicating RNA in a membrane.

• Metabolism evolved from glycolysis to photosynthesis to oxidative metabolism.

• Two prokaryotic domains (Bacteria, Archaea) diverged early; eukaryotes evolved from Archaea with organelles from endosymbionts.

• Multicellularity evolved independently, leading to cell specialization.

• Understanding cells is fundamental to medicine, biotechnology, and agriculture.