part 1 cell bio

Cell Structure, Function, and Principles of Development

Bacterial Cells Introduction

  • Overview of cell and developmental biology.

  • Reference to diagrams depicting bacterial (Fig. 27.2) and animal cells (Fig. 6.8).

Instructor Background

  • Dennis O. Clegg:

    • BS and PhD in Biochemistry.

    • Postdoctoral research in Neuroscience.

    • Professor since 1988.

    • Expertise in stem cell biology, neuroscience, bacterial behavior, and plant biochemistry.

Regenerative Patch Technologies, LLC

  • Co-Founder of biotechnology startup focused on cell-based implant technology for retinal disease treatment.

  • Founded by Drs. Mark Humayun, David R. Hinton, and Dennis O. Clegg.

  • The technology related to the CPCB-RPE1 implant is exclusively licensed from prominent California universities.

Schedule of Lectures

  • Lectures 2 and 3 on the following dates will be asynchronous; materials will be available on Canvas.

Office Hours

  • Held in-person post-lecture outside Campbell Hall at 9:00 AM.

  • Virtual office hours on Fridays from 9:30 to 10:30 AM on Zoom.

  • Specific Zoom links and dates provided for office hours.

Quizzes Schedule

  • Quiz 6 opens at noon on November 21, closes at midnight on November 25.

  • Quiz 7 opens at noon on December 5, closes at midnight on December 9.

Final Exam

  • Scheduled for December 12 at 8:00 AM.

  • The exam will exclusively cover lecture content, with assigned readings for comprehension enhancement.

Learning Objectives for Cell and Developmental Biology

  1. Identify how macromolecules comprise cells and tissues.

  2. Understand the structure and functions of various cell parts.

  3. Explore experimental methodologies in cellular studies.

  4. Analyze how cellular defects can lead to diseases.

  5. Grasp fundamental principles of biological development.

  6. Investigate potential therapeutic applications of cells.

Case Study: Traumatic Spinal Cord Injury of Jake Javier

  • Incident description: Jake suffered a spinal injury from hitting his head at the pool.

  • Experience of profound helplessness followed by drowning fears.

  • Explanation of spinal cord neuron functions: communication from brain to body and sensory feedback.

  • Notable fact: Neurons in the central nervous system have a limited capacity for regeneration.

Research on Functional Recovery Post-Injury

  • Research conducted by Yang D. Teng et al. on polymer scaffolds infused with neural stem cells for spinal cord injury therapy.

  • Published findings in Proceedings of the National Academy of Sciences USA, 2002.

Clinical Trial Example

  • Kris Boesen, paralyzed after a car accident, regained limited hand and arm function post neural stem cell therapy.

  • Alternatively sourced stem cells from human embryonic cells were part of the patient’s treatment at USC.

Biological Scale

  • Illustration of various biological scales (Fig. 6.2):

    • Human height: 10 m

    • Length of some nerve/muscle cells: 1 m

    • Chicken egg: 1 cm

    • Human egg: 100 μm

    • Most cells: 10 μm

    • Viruses: 100 nm

    • Proteins: 10 nm

    • Atoms: 0.1 nm

Historical Context of Cell Discovery

  • Robert Hooke (1605-1703): Coined the term “cell.”

    • Observed cork cells, which are actually cell walls, not living cells.

    • Cork cell walls are made primarily of cellulose with suberin.

  • Antoni van Leeuwenhoek (1632-1723): First to observe bacteria and sperm cells, described them as “animalcules.”

Human Body Cell Count

  • Approximately 37.2 trillion cells.

  • Exploration of various cell types within the human body.

Transcriptomic Diversity in Human Brain Cells

  • Research on single-nucleus RNA sequencing reveals extensive diversity across approximately 3 million brain cells, identifying 3,313 cell types in total.

Microscopy Techniques Overview

  • Essential methods in modern microscopy:

    • Brightfield

    • Phase contrast and differential interference contrast

    • Fluorescence microscopy

    • Electron microscopy (e.g., SEM, TEM)

  • Differences in live vs. fixed samples.

Diffusion Principles in Cell Structure

  • Definition: Random motion of molecules due to kinetic energy.

  • Key processes in efficiency of nutrients and waste movement dependent on cell size and surface-to-volume ratio.

Prokaryotic vs. Eukaryotic Cells

  • Overview of features:

    • DNA, membrane-bound cells, ribosomes present in both.

    • Variations in structure, size, and function.

    • Importance in health and disease context, particularly infectious disease.

Antibiotic Mechanism: Penicillin

  • Discovered by Alexander Fleming in 1928; effective against bacterial infections by targeting bacterial cell walls (peptidoglycan).

Insulin: Overview and Discovery

  • Discovered in the 1920s; significant medical advancement for diabetes treatment.

  • Understanding its secretion pathway and role in glucose metabolism.

Endomembrane System Details

  • Components:

    • Rough and Smooth ER distinctions, functions including protein synthesis and lipid metabolism.

    • Golgi complex functions in modification and transport of proteins.

Lysosomal Functionality and Diseases

  • Lysosomes: Recycling center of the cell housing digestive enzymes.

  • Example Disease: Tay-Sachs Disease connected to lysosomal deficiencies.