#1 Intro to Anatomy Lect Notes

Introduction to Anatomy

Overview

  • Human Anatomy: Study of structures within the human body.

  • Gross Anatomy: Structures visible to the naked eye.

  • Histology: Study of tissues under a microscope.

Etymology and Terminology

  • Etymology: Understanding root meanings of anatomical terms aids learning.

    • Example: "Anatomy" (Greek: ana = up/apart, tome = cutting).

  • Grammar in Anatomy: Blueprints for combining words (nouns, adjectives).

    • Example: "Cranium" (noun) vs. "Cranial" (adjective).

  • Spelling: Precision needed due to similar terms in anatomy; e.g., conoid, coronoid, coracoid.

Levels of Organization

  • Structure hierarchy from smallest to complex:

    • Atoms ➜ Molecules ➜ Organelles ➜ Cells ➜ Tissues ➜ Organs ➜ Organ Systems ➜ Organism.

Basic Functions of Living Organisms

  • Functions include:

    • Responsiveness

    • Growth

    • Differentiation

    • Metabolism

    • Movement

    • Reproduction

    • Excretion

Identifying Body Systems

  • Tissues:

    • Epithelium

    • Connective

    • Muscular

    • Nervous

  • Integumentary: Skin, hair, nails.

  • Skeletal: Bones and cartilage.

  • Muscular: Skeletal, cardiac, smooth muscles.

  • Nervous: CNS and PNS.

  • Endocrine: Glands.

  • Cardiovascular: Heart and vessels.

  • Respiratory: Lungs and airways.

  • Digestive: Organs from mouth to anus.

  • Urinary: Kidneys and excretion organs.

  • Reproductive: Male and female structures.

Body Cavities

  • Dorsal Cavity: Cranial cavity (brain) and Spinal cavity (spinal cord).

  • Ventral Cavity: Thoracic (lungs and heart) and Abdominopelvic (digestive and reproductive organs).

Anatomical Position

  • Standard reference frame: Standing upright, arms at sides, palms forward.

  • Positions: Supine (lying back) vs. Prone (lying stomach).

Anatomical Directions

  • Terms used to describe location/movement:

    • Superior/Inferior

    • Anterior/Posterior

    • Dorsal/Ventral

    • Deep/Superficial

    • Distal/Proximal

    • Lateral/Medial

Summary of Cytology

  • Basic cell properties: structures, functions, and types indicated by names.

  • Importance of microscopy in examining cells and tissues.

  • Objectives: Understand terminology, body structure organization, body cavities, and cellular organization.

A. Cell Membrane

  1. Functions as almost everything!

  • Creates the cell boundary, separating the inside of the cell from the outside.

  • Allows for adhesion and attachments to other membranes.

  • Has receptors for hormones, neurotransmitters, and other signals for communication.

  • Has identifying markers to indicate function to other cells.

B. Special Features on Cells

  1. Cilia - hair-like structures that arise from the exposed (apical) end of some cells; role is for movement of substances across the surface of the cell, e.g., mucus.

  2. Microvilli - extensions of cell membrane to increase the surface area of the cell for exchange, e.g., to increase the rate of absorption.

  3. Flagellum - whip-like structure for the movement of the entire cell, e.g., spermatozoa.

II. Cell Membrane Permeability

  • What substances can move across the plasma membrane of a cell?

    1. Impermeable - restricts the passage of all molecules.

    2. Selectively permeable - lets certain molecules through but not others.

    3. Highly permeable - lets almost anything through the cell membrane.

III. Cell Attachments and Junctions

  1. Tight junction - near free surface (apical end) of epithelium, watertight seal.

  2. Desmosome - lightly tacks cells together, usually deep to the surface (basal end).

  3. Hemidesmosomes - tethers cells to basement membrane where cells are anchored.

  4. Gap junction - physical opening between two cells, permits direct communication of ions, etc.

IV. Cell Names

  • Names of cells often indicate their location and function.

  • In general, the term -cyte means a mature cell that resides in and maintains that tissue (e.g., a chondrocyte in cartilage).

  • Hepatocytes are found in the liver, neurons are for nervous system communication, and adipocytes are found in adipose tissue, where they store triglycerides (fat).

  • Various cell types can also have special endings; for example, the suffix (ending) -blast indicates a cell that makes or builds something (e.g., a fibroblast makes fibers).