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.