Ch 1 A & P Flashcards
Generates the physical force to make the body structures move
Arranged in bundles
Contractile cells that provide the ability to move the body in three dimensions
Well supplied with blood vessels (lots of energy and waste requirements)
Muscle Tissue
Detects changes inside/outside the body
Initiates and transmits nerve impulses that coordinate body activities and help maintain homeostasis
Nervous Tissue
Integumentary system is comprised of:
Skin, Hair, Nails
Accessory structures
Covers body surfaces; lines body cavities, hollow organs, and ducts; and forms glands
Epithelial Tissue
Medical term for skin and main portion of the integumentary system
Epithelium
Protects and supports the body and its organs
- Binds organs together
- Stores energy reserves as fat
- Provides immunity
Connective tissue
Provide contact or adhesion between neighboring cells or between a cell and extracellular matrix
Maintain paracellular barrier of epithelia and control transport of materials or signals between cells
Cell Junctions
Cell junctions are dense in _______ tissues because the needs to maintain both strength and integrity in a wide variety of conditions
Epithelial
Form a barrier against water and antigens passing between individual epithelial cells
Tight Junctions
Cell-to-cell adhesions continuously assembled and disassembled so cells can respond to changes in their microenvironment
Adherens Junctions
Form stable adhesion junctions between cells
Desmosomes
Allows various molecules and electrical signals to pass freely between cells
Gap junctions
Facilitate the stable adhesion of basal epithelial cells to the underlying basement membrane
Hemidesmosomes
Two broad categories of epithelial tissue
Covering & Lining epithelium
Glandular epithelium
Covers external surfaces of the body and some internal organs
Lines body cavities, blood vessels, and ducts
Lines interior of respiratory, GI, urinary and reproductive systems
Integral part of sense organs for hearing, vision and touch
Covering and lining epithelium
Secreting portion of the glands, such as sweat glands
Glandular epithelium
Most superficial layer of cells
Apical layer
Deepest layer of the cell
Basal layer
Thin extracellular structure composed mostly of protein fibers
Located between the epithelium and underlying connective tissue layer
Helps to bind and support the epithelium
Basement membrane
Two ways of classifying epithelial tissue
Morphology
Stratification
Classification of epithelial cells based on shape
Morphology
Classification of epithelial cells based on number of layers
Stratification
Thin, flat shape allows rapid passage of substances through them
Can be keratinized or non-keratinized; wet or dry depending on their location
Squamous epithelium
Found in areas such as the lining of the esophagus, mouth and cervix
Squamous Epithelium
Tall as they are wide and shaped like cubes or hexagons
Frequently have microvilli at apical surface
Function in either secretion of absorption
Cuboidal epithelium
Found in areas such as the salivary glands and thyroid follicles
Cuboidal epithelium
Taller than they are wide
Protect underlying tissues
Apical surfaces may have cilia or microvilli
Often specialized for secretion and absorption
Columnar epithelium
Lines most organs of the GI tract, respiratory tract, and fallopian tubes
Columnar epithelium
Able to change shape from flat to cuboidal and back depending on tension and distention of tissue
Useful for organs such as the urinary bladder, when it is stretching (distend) to a larger size and as it collapses to a smaller size
Transitional epithelium
A single layer of cells that functions in a diffusion, osmosis, filtration, secretion and absorption
Simple epithelium
Simple epithelium that appears to be stratified because the nuclei lie at different levels and not all cells reach the apical surface
Pseudostratified epithelium
Specialized type of pseudostratified cells that secrete mucus and are an integral part of mucous membranes
Goblet cells
Cilia provide two forms of locomotion depending on the cell
Movement of the cell itself
Movement of particles or substance across or around the cell
Increase the surface area of a cell by multiplying the area from 2 dimensions to 3 dimensions
Enable the absorption and secretion of far more nutrients/material
Microvilli
Help anchor sperm to the egg and allow for easier fertilization
Act as an anchoring point and aid in the migration of WBCs
May sweep unwanted materials toward an absorptive area of the cell
Microvilli
Highly-insoluble fibrous protein with water proofing qualities and high friction resistance
Keratin
Epithelial cells infused with keratin in the stratum basale of the epidermis
Keratinocytes
Lose their nucleus and organelles to make room for keratin; they are no longer living cells
Keratinocytes
Found on wet/interior surfaces exposed to considerable wear and tear
Lining of mouth cavity, tongue, pharynx, esophagus, and vagina
Non-keratinized epithelium
Found on dry/outer surfaces where resistance to both friction and water is needed
Outer epidermis consists of keratinocytes that provide protection against water, friction, abrasion, and microorganisms
Keratinized stratified epithelium
Supports and physically connects other tissues/cells together to form the organs of the body
Connective tissue
More cells; Less extracellular space
Epithelial tissue
Less cells; More extracellular space
Connective Tissues
Three components of connective tissue
Resident cells
Extracellular Matrix
Protein fibers
Extracellular material produced by the connective tissue cells embedded within it.
Major component is ground substance crisscrossed by protein fibers
Matrix
Most common cells in connective tissue
Produce and maintain most of the tissue’s extracellular components
Synthesizes and secretes collagen and elastin
Fibroblasts
Fat cells or adipose cells or adipose tissue
Specialized for cytoplasmic storage of lipid as neutral fats, or less commonly for production of heat
Large population serves to cushion and insulate the skin and other organs
Adipocytes
Components of loose connective tissues, often located near blood vessels in the skin
Function in localized release of compounds important to inflammatory response, innate immunity, and tissue repair
Mast Cells
Most abundant protein in the body (25% of all protein)
Very strong and resistant to shear forces
Key element of all connective tissues, as well as epithelial basement membranes
Collagen fibers
Composed of elastin
Strength and elasticity
Have rubberlike properties that allow tissue containing these fibers to be stretched or distended and return to their original shape
Elastic fibers
Where are elastic fibers found?
Stroma of the lungs
Composed of glycogen and glycoprotein
Provide strength and support in the walls of small blood vessels
Supporting framework of many soft organs; most notably the immune system, liver, endocrine glands, spleen and lymph nodes
Reticular fibers
Lines entire GI, respiratory, reproductive, and much of the urinary system
Epithelial layer secretes mucous via goblet cells
- Prevents cavities from drying out
- Traps particles in the respiratory tract
- Lubricates and absorbs food as it moves through the tract, secretes digestive enzymes
- Helps bind the epithelium to underlying structures
Mucous membranes
Lines body cavity that doesn’t open directly to exterior and covers organs that lie within the cavity
Includes parietal, visceral, mesothelium, pleura, pericardium, peritoneum
Serous membranes
Lines joints
Composed of areolar connective tissue and adipose tissue with collagen fibers
No epithelial layer
Synovial membranes
Reduces frictions, lubricates and nourishes cartilage, and removes microbes/debris from the joint
Synovial fluid
Surface layer
Comprised of epithelial tissue
Epidermis
Lies inferior/deep to the epidermis
Comprised of connective tissue
Dermis
Lies inferior/deep to the dermis
Not part of the skin
Subcutaneous
Epidermis primarily consists of:
Continually regenerating keratinocytes
Lifecycle of keratinocytes
30 days
Thickness of eyelids
75-150 micrometers
Thickness of palms and soles
0.4 to 1.5 mm
Epidermis lacks any vascular structures and obtains all nutrients from the dermal vasculature by ________
Diffusion
Epidermis Layer
- Cells consist mostly of keratin
- Cells are shed and replaced from below
Stratum Corneum
Epidermis Layer
-Found only in palms and soles of hands and feet
Stratum Lucidum
Epidermis Layer
- Losing cell organelles and nuclei
- Infusion of waterproofing lipids
Stratum Granulosum
Epidermis Layer
-Cells beginning to flatten
Stratum Spinosum
Epidermis Layer
-Stem cell layer, new cells arise here
Stratum Basale
Layer of skin located between the epidermis and subcutaneous tissues
Dense irregular connective tissue and functions to cushion the body from stress and strain
Dermis