Exam A Study Guide Flashcards

Tissue Types

  • Epithelial Tissue

    • Covers body surfaces, lines cavities and forms glands.
    • Functions: Protection, secretion, absorption, and filtration.
    • Examples: Skin surface, lining of the GI Tract.
    • Cells: Squamous, Cuboidal, Columnar
  • Connective Tissue

    • Supports, protects, and binds tissues and organs.
    • Functions: Structural support, storage, and immune defense.
    • Examples: Bone, blood, fat, and tendons.
    • Cells: Fibroblast, adipocytes, & macrophages.
  • Muscle Tissue

    • Responsible for movement.
    • Functions: Produces body movement, maintains posture, and generates heat.
    • Examples: Heart, biceps (skeletal), intestines (smooth).
    • Cells: Skeletal muscle Fibers, Cardiomyocytes, Smooth muscle cells.
  • Nervous Tissue

    • Detects stimuli and transmits impulses.
    • Function: Communication via electrical signals.
    • Examples: Brain, spinal cord, and peripheral nerves.
    • Cells: Neurons & glial cells

Epithelial Tissue

  • Functions

    • Protection, secretion, absorption, filtration.
  • Classification by Layers

    • Simple: One layer.
    • Stratified: Multiple layers.
    • Pseudostratified.
  • Classification by Shape

    • Squamous: Flat.
    • Cuboidal: Cube-shaped.
    • Columnar: Tall.

Glands

  • Sweat Glands: Cool the body through sweat.

  • Sebaceous Glands: Secrete sebum to lubricate skin/hair.

  • Ceruminous Glands: Produce earwax (cerumen) for protection.

  • Endocrine vs. Exocrine

    • Endocrine: Release hormones into blood (e.g., thyroid).
    • Exocrine: Release substances through ducts (e.g., sweat, salivary glands).
  • Secretion Methods

    • Merocrine: Secrete via exocytosis (e.g., sweat).
    • Apocrine: Secrete via partial cell loss (e.g., mammary glands).
    • Holocrine: Whole cell disintegrates to release contents (e.g., sebaceous glands).

Connective Tissue

  • Components

    • Cells (e.g., fibroblast).
    • Fibers (collagen, elastic, reticular).
    • Ground substance.
  • Protein Fibers

    • Collagen: Provides tensile strength.
    • Elastic: Provides flexibility/stretch.
    • Reticular: Provides a supportive mesh.
  • Types of Connective Tissue

    • Loose (areolar & adipose).
    • Dense (tendons).
    • Cartilage.
    • Bone.
    • Blood.
  • Types of Cartilage

    • Hyaline: Ends of bones, nose, trachea.
    • Elastic: External ear, epiglottis.
    • Fibrocartilage: Intervertebral disc, pubic symphysis.

Muscle Tissue

  • Skeletal Muscle

    • Voluntary, striated, multinucleated.
  • Cardiac Muscle

    • Involuntary, striated, intercalated discs, one nucleus.
  • Smooth Muscle

    • Involuntary, non-striated, one nucleus.

Nervous Tissue

  • Cells
    • Neurons: Transmit impulses.
    • Glial Cells: Support, protect, and nourish neurons.

Tissue Repair

  • Process: Inflammation --> Organization --> Regeneration or fibrosis.
  • Inflammation: Brings immune cells to start healing.
  • Best Healing Tissue: Epithelial and connective (like bone).
  • Worst Healing Tissue: Nervous and cardiac.

Skin Layers

  • Epidermis Layers (Superficial to Deep)

    • Stratum corneum: Dead keratinized cells.
    • Stratum lucidum: Only in thick skin.
    • Stratum granulosum: Keratinization begins.
    • Stratum spinosum: Desmosomes, strength.
    • Stratum basale: Mitotic layer, melanocytes.
  • Functions of the Skin

    • Protection, regulation, sensation, excretion, vitamin D synthesis.
  • Epidermis Cell Types

    • Keratinocytes.
    • Melanocytes.
    • Langerhans cells.
    • Merkel cells.

Dermis

  • Layers

    • Papillary: Loose connective tissue, capillaries, sensory neurons.
    • Reticular: Dense connective tissue, collagen, elastic fibers.
  • Cells of the Skin

    • Keratinocytes: Main structural cell, keratin production.
    • Melanocytes: Pigment production.
    • Langerhans: Immune defense.
    • Merkel Cells: Sensory.

Glands of the Skin

  • Sebaceous: Oil secretion (sebum).
  • Sweat
    • Eccrine sweat glands: Thermoregulation, watery.
    • Apocrine sweat glands: Found in armpits/groin, thicker sweat.
    • Acne: Inflammation of clogged sebaceous glands.
    • Composition of Sweat: Water, salts, urea, lactic acid.

Sensory Receptors of the Skin

  • Meissner Corpuscles: Light touch.
  • Pacinian Corpuscles: Deep pressure.
  • Merkel Discs: Steady pressure.
  • Free nerve endings: Pain & temperature.

Homeostatic Imbalances

  • Conditions like eczema, psoriasis, infections, or burns can change skin's appearance.

Burns

  • 1st Degree: Epidermis only (no pain).
  • 2nd Degree: Epidermis and part of dermis (blisters).
  • 3rd Degree: Full thickness; nerve damage, white/charred.
  • Why are 3rd-degree burns deadly? Fluid loss, infection risks, inability to regulate body temp.

Skin Cancers

  • Risk Factors: Overexposure to UV radiation, frequent irritation of skin.

  • Three Major Types

    • Basal cell carcinoma: Most common, least dangerous.
    • Squamous cell carcinoma: Can spread, more aggressive.
    • Melanoma: Arises from melanocytes, highly metastatic & deadly.