Bio Lecture 3

Introduction

  • The lab exam is not complete yet, and there is still next week for completion.

    • Open lab times will be available for students who need more information.

    • Reminder about the schedule and structure of the course.

Course and Exam Overview

  • Weather conditions are not expected to affect the upcoming lectures.

  • Next Wednesday, students will take the first exam, ending the current unit of study.

  • The previous week's lecture introduced the course materials, focusing on basic anatomy and terminology.

Content Review

Previous Topics Covered

  • Anatomical Terms Covered:

    • Basic anatomical terms, directional terms, anatomical position, body planes, body regions.

  • The material was introductory; most students have prior exposure before this course.

Upcoming Topics

  • Today’s focus:

    • Basic Cells

    • Basic Tissues

  • Followed by the next unit which will cover specific tissues and body systems in week four.

Lab Component

  • Current lab work focuses on gross anatomy.

  • Topics in Unit Two will include:

    • Upper extremity bones, muscles, blood vessels, nerves, skin, and joints.

First Exam Details

  • Scheduled for next Wednesday.

  • Format: 50 questions, 1 point each, totaling 100 points.

  • Content includes only three chapters: relevant material outlined.

  • Students must bring compatible devices for using the Respondus LockDown Browser.

    • Not allowed to take the exam on a cell phone; must use a tablet or laptop.

Device Issues

  • Options for those without a device:

    • Borrow from friends or family.

    • Check availability in the library.

    • Schedule use at the testing center, no walk-ins allowed.

Exam Preparation Recommendations

  • Advise to overprepare for the exam.

  • Exam performance can be adjusted since it only counts 3 points out of a total of 2000 course points.

  • Concerns about the volume of information and pace of the course.

Study Materials

  • Emphasis on SmartBook readings:

    • Optional but recommended for exam preparation.

    • Can help familiarize students with questioning styles relevant to exams.

Lecture Structure

Presentations of Material

  • Dr. Morford has recorded lectures for each chapter, providing detailed explanations.

  • Lectures in class will be focused on highlights and actionable content.

  • Students to feel free to ask questions throughout the session.

Cells and Tissues

General Concepts

  • Overview of the relationship between:

    • Cells > Tissues > Organs > Organ Systems > Organism (Human).

  • Cytology: The study of cells.

    • Basic cell functions discussed, highlighting:

    • Nutrient intake and waste disposal.

    • Structural integrity and reproduction.

Cellular Structures

  • Essential Parts of a Cell

    • Plasma Membrane, Cytoplasm, Nucleus (the three main components).

    • Differences between structures like membrane types in different cells (e.g., neuron).

Plasma Membrane

  • Alternate names: Plasma lemma, neurolemma (in neurons).

  • Characteristics of the plasma membrane:

    • Semi-permeable/selectively permeable, controlling material entry/exit.

  • Composition:

    • Phospholipid Bilayer: Polar heads (hydrophilic) and nonpolar tails (hydrophobic).

  • Role of Cholesterol and Proteins in membrane structure and function:

    • Integral Proteins (channels, receptors) and Peripheral Proteins (enzymes, signaling).

Cytoplasm

  • Three components:

    • Cytosol: Fluid part (mostly water).

    • Inclusions: Storage components (e.g., glycogen).

    • Organelles: Functional structures ('small organs')

  • Key organelles discussed:

    • Endoplasmic Reticulum (Rough and Smooth), Golgi Apparatus, Lysosomes, Mitochondria, Ribosomes, Cytoskeleton, Centrioles.

Organelles Explained

  • Endoplasmic Reticulum (ER):

    • Rough ER: Studded with ribosomes for protein synthesis.

    • Smooth ER: Synthesis of lipids, detoxification processes.

  • Golgi Apparatus: Processes, packages, and ships proteins.

  • Lysosomes: Garbage disposal; breakdown of waste within the cell.

    • Autophagy (self-eating) and Autolysis (self-destruction).

  • Mitochondria: ATP production (energy currency of the cell); has its DNA.

  • Ribosomes: Protein synthesis sites; can be free or attached to ER.

  • Cytoskeleton: Provides structure with microfilaments, intermediate filaments, and microtubules.

    • Key roles in cell shape, movement, and stability.

Cell Movement Structures

  • Cilia and Flagella

    • Flagella: Move the entire cell (e.g., sperm).

    • Cilia: Move substances across the cell surface (e.g., respiratory tract).

  • Microvilli: Increase absorption surface area without movement.

Nucleus Structure

  • Components: Nuclear envelope, nucleoli, chromatin.

  • DNA structure: Sugar-phosphate backbone, nitrogenous bases (A, T, C, G).

Tissue Types Overview

Tissue Classification

  • Histology: The study of tissues.

    • Four major types: Epithelial, Connective, Muscle, Nervous.

Epithelial Tissue

  • Definition and characteristics:

    • Avascular, cellularity, regenerates quickly.

    • Functional roles (protection, secretion, sensation).

    • Surface polarization: Apical (top) and Basal (bottom).

  • Connection features (junctions): Tight junctions, desmosomes, gap junctions.

Connective Tissue

  • Functions: Support, protection, storage, transport.

    • Distinguished by a matrix—characteristics determined by the type of connective tissue.

    • Major categories include Proper (Loose or Dense), Supporting (Cartilage, Bone), Fluid (Blood, Lymph).

Muscle Tissue

  • Types: Skeletal (voluntary, striated), Cardiac (involuntary, striated, intercalated discs), Smooth (involuntary, non-striated).

Nervous Tissue

  • Main cell types: Neurons (functional units), Glial cells (supportive role).

  • Neuron structure: Dendrites receive signals, cell body processes, axon transmits signal.