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ES207: Human Form and Function 1 — Core Notes

Anatomy vs Physiology

  • Anatomy: investigates body structure; etymology implies to dissect.
  • Physiology: investigates processes and functions.
  • Human Physiology: studies the human organism.
  • Systemic Physiology: studies body organ-systems.
  • Cellular Physiology: studies body cells.

Structural and Functional Organization

  • Six levels from chemical to organism: 1 Chemical, 2 Cellular, 3 Tissues, 4 Organs, 5 Organ systems, 6 Organism.
  • Examples of components: mitochondria, nucleus, organelles; tissues, organs, organ systems.

Major Concepts and Life Processes

  • Characteristics of life (brief): organization, metabolism, responsiveness, growth, development, reproduction, homeostasis.
  • Homeostasis: maintenance of a constant internal environment; set point and normal range; variables include temperature, heart rate, BP, etc.
  • Negative feedback is the main homeostatic mechanism; components: receptor, control center, effector; steady state is a temporary new equilibrium under changed demands.

Directional Terms and Anatomical Position

  • Anatomical position: standing erect, face forward, palms forward.
  • Directional terms (essential):
    • Superior vs Inferior; Anterior (ventral) vs Posterior (dorsal);
    • Medial vs Lateral; Proximal vs Distal; Superficial vs Deep; Ipsilateral vs Contralateral.

Body Planes and Sectioning

  • Sagittal planes (left-right); Midsagittal plane (midline, equal left/right).
  • Transverse (horizontal) plane: superior vs inferior.
  • Frontal (coronal) plane: anterior vs posterior.

Body Cavities and Serous Membranes

  • Dorsal cavity: protects nervous system; includes cranial cavity and vertebral canal.
  • Ventral cavity: houses most internal organs; subdivided into Thoracic and Abdominopelvic cavities.
  • Serous membranes: parietal and visceral layers with a lubricating serous cavity.
    • Pericardial cavity (pericardium), Pleural cavities (pleura), Peritoneal cavity (peritoneum).

Major Body Systems (Overview of Organization)

  • Integumentary, Skeletal, Muscular, Nervous, Endocrine, Cardiovascular, Lymphatic/Immune, Respiratory, Digestive, Urinary, Reproductive, etc. (high-level reference for organ-system organization).

Cells, Membranes, and Transport

  • Cell membrane: phospholipid bilayer with hydrophilic heads and hydrophobic tails; selective permeability.
  • Movement through membrane:
    • Diffusion, Osmosis, Facilitated diffusion (no ATP).
    • Carrier-mediated transport; channels (leak vs gated).
    • Active transport requires ATP (e.g., Na+/K+ pump).
    • Vesicular transport: endocytosis and exocytosis.
  • Endocytosis types: receptor-mediated, phagocytosis, pinocytosis.
  • Endocytosis and exocytosis maintain intracellular environment and intercellular communication.

Diffusion, Osmosis, and Membrane Transport Details

  • Diffusion: movement down a concentration gradient; rate increases with gradient steepness and temperature.
  • Osmosis: diffusion of water across a selectively permeable membrane; osmotic pressure.
  • Solutions terminology: hypotonic, isotonic, hypertonic relative to cell cytoplasm.
  • Facilitated diffusion uses channels or carrier proteins; still concentration-gradient driven.

Active Transport and Energy Systems

  • Active transport: carrier-mediated, energy (ATP) required; moves substances against gradient.
  • Secondary active transport uses the gradient established by primary active transport.
  • Sodium-Potassium pump: maintains Na+ outside and K+ inside; essential for resting membrane potential.
  • Energy for exercise: interplay between anaerobic and aerobic pathways depending on duration/intensity.

Energy and Chemical Reactions

  • Energy is the capacity to do work; work = moving matter.
  • Kinetic energy: energy in motion; Potential energy: stored energy.
  • Chemical reactions: synthesis, decomposition, exchange; reversibility and equilibrium.
  • Activation energy and enzymes: enzymes lower activation energy; do not change end products; many enzymes end in -ase.
  • Rate factors: catalyst, reactant concentration, temperature.
  • ATP as the energy currency; ATP production routes:
    • Anaerobic: ATP-PC system and glycolysis (glucose → 2 pyruvic acid or 2 lactate); glycolysis yields 2 ATP per glucose; occurs in cytoplasm.
    • Aerobic: Krebs cycle + Electron Transport Chain; main ATP production, ~32 ATP per glucose.
  • Interplay: short, high-intensity activity relies more on anaerobic pathways; longer, moderate activity relies more on aerobic metabolism.

Tissues: Overview

  • A tissue is a group of cells with similar structure and function plus surrounding extracellular matrix; histology is the study of tissues.
  • Four primary tissue types: 4 types.

Epithelial Tissues

  • Characteristics: mostly cells, covers surfaces, avascular, regenerative, specialized cell connections.
  • Classification by layers and shape: simple, stratified, pseudostratified; squamous, cuboidal, columnar; transitional shapes.
  • Functions: protection, barrier, secretion, absorption; includes glands (exocrine and endocrine).
  • Notable types: Simple squamous, Simple cuboidal, Simple columnar, Pseudostratified columnar, Stratified squamous (keratinized and non-keratinized), Transitional epithelium.

Connective Tissues and Cartilage

  • Connective tissue characteristics: cells separated by extracellular matrix (ECM); ECM includes fibers and ground substance.
  • ECM components: protein fibers (collagen, reticular, elastic), ground substance, and fluid.
  • Loose connective tissue: areolar, adipose, reticular.
  • Dense connective tissue: dense regular (tendons/ligaments), dense irregular, elastic.
  • Cartilage: hyaline, fibrocartilage, elastic cartilage.
  • Bone and Blood: bone as mineralized matrix with osteocytes; blood as fluid connective tissue with plasma and formed elements.

Cartilage Details

  • Hyaline cartilage: most common; covers joint surfaces; flexible and supportive.
  • Fibrocartilage: strong, withstands compression; intervertebral disks, knee joints.
  • Elastic cartilage: with elastic fibers; external ear, epiglottis.

Bone and Other Connective Tissues

  • Bone: hard connective tissue; osteocytes in lacunae; compact and spongy bone; provides support and protection.
  • Blood: fluid connective tissue; transports gases, nutrients, wastes; immune function.

Muscle Tissue

  • Three types: 3 types: skeletal, cardiac, smooth.
  • Skeletal: voluntary, striated, attaches to bone.
  • Cardiac: involuntary, striated, branched with intercalated disks; pumps blood.
  • Smooth: involuntary, non-striated; lines hollow organs.

Nervous Tissue

  • Neurons: transmit electrical signals; dendrites, cell body, axon.
  • Glial cells: support, protection, and myelin formation.
  • Location: brain, spinal cord, nerves.

Integumentary System

  • Components: skin and accessory structures (hair, glands, nails).
  • Functions: protection, sensation, vitamin D production, temperature regulation, excretion (minor).
  • Skin layers: epidermis (keratinized stratified squamous) and dermis (dense connective tissue); subcutaneous tissue (hypodermis) lies beneath.
  • Epidermis strata: stratum corneum (dead keratinized cells) and deeper layers where mitosis occurs.
  • Dermis features: collagen and elastic fibers; cleavage (tension) lines; dermal papillae form fingerprints.
  • Skin color determinants: melanin, carotene, blood flow; melanin produced by melanocytes and transferred to epithelial cells; albinism is melanin production deficiency.
  • Glands: sebaceous, eccrine (thermoregulation, watery secretion), apocrine (puberty-related, odor with bacterial action).
  • Hair and nails: hair shaft, hair follicle, arrector pili; nails protect digits.
  • Skin cancers: basal cell carcinoma, squamous cell carcinoma, malignant melanoma.
  • Burns: first-degree (epidermis only), second-degree (epidermis and dermis), third-degree (full thickness); healing and grafts.
  • Vitamin D production: UV light initiates synthesis, liver and kidney conversions activate vitamin D for calcium absorption.
  • Temperature regulation: vasodilation and sweating promote heat loss; vasoconstriction conserves heat.

Skin Pathologies and Diagnostics

  • Diagnostic indicators: cyanosis (bluish skin from low O2), jaundice (yellow from liver dysfunction), rashes and lesions can indicate systemic issues.

Quick Reference for Key Numbers and Terms

  • Four tissue types: 4.
  • Three muscle types: 3.
  • Six structural levels: 6.
  • Enzymes typically end in -ase: suffix indicator.
  • ATP yield (aerobic): approximately 32 ATP per glucose.
  • Glycolysis yield: 2 ATP per glucose (anaerobic).
  • Cartilage types: 3 (hyaline, fibrocartilage, elastic).
  • Skin layers: epidermis and dermis; stratum corneum is the outermost epidermal layer.
  • Glands: eccrine and apocrine; sebaceous glands secrete sebum.
  • Burns: first-, second-, third-degree classifications by depth.
  • pH neutral value: 7 (isotonic reference).

Vitamin D, Temperature Regulation, and Excretion (Integumentary Focus)

  • Vitamin D supports calcium absorption; activation occurs in liver and kidneys.
  • Temperature regulation relies on dermal blood flow and sweat glands; excretion via sweat is minor.
  • Integumentary system provides diagnostic cues for systemic health (rashes, cyanosis, jaundice).