Chapter 4 Flashcards
Histology
The study of tissues
Simple epithelium
Contains one layer of cells and all cells touch the basement membrane
Stratified epithelium
Contains more than one layer. Some cells rest on top of others and don’t touch basement membrane
Simple squamous epithelium
Single row of thin/flat cells. Permits rapid diffusion or transport of substances
Secretes serous fluid and found non the inside of tubes, alveoli, glomeruli, endothelium, and serosa
Simple cuboidal epithelium
Job: absorption and secretion, mucus production and movement
Found in: liver, thyroid, mammary and salivary glands, bronchioles, and kidney tubules
Simple columnar epithelium
Brush the border of microvilli and can be ciliated in some organs. May posses goblet cells.
Job: absorption and secretion; mucus secretion
Found in: lining of Gl tract, uterus, kidney and uterine tubes
Psuedostratified epithelium
Has nuclei at several layers with cilia and goblet cells
Job: secretes and propels mucus
Found in: respiratory tract and portions of male urethra
Keratinized stratified squamous
Resists abrasion; retards water loss through skin; resists penetration by pathogenic organisms
Cells on its apical surface give it its name
When cells are keratinized they are dead (no nucleus)
Found in: epidermis; Palms and soles
Non-keratinized stratified squamous
Same as keratinized but without dead cells ( resists abrasion and penetration of pathogens)
Found in: tongue, oral mucosa, esophagus and vagina
Apical cells are what name them
Stratified cuboidal
Surface cells are square or round
Secretes sweat; sperm production and produces ovarian hormones
Found in: sweat glands ducts, ovarian follicles and seminiferous tubules
Transitional epithelium
Multilayered epithelium surface cells that change from rounds to flat when stretched
Allows for filling of urinary tract
Found in: ureter and bladder
Connective tissue
Less cellular than epithelial
Contains collagen
Ground substance between cells
Types of fibrous connective tissue
Loose connective tissue
Dense connective tissue
Areolar tissue (loose connective)
Loosely organized fibers, abundant blood vessels, and a lot of seemingly empty space
Underlies all epithelia, in serous membranes, between muscles, passageways for nerves and blood vessels
Reticular tissue (loose connective)
Mesh of reticular fibers and fibroblasts
Forms supportive stroma (framework) for lymphatic organs
Found in lymph nodes, spleen, thymus and bone marrow
Dense regular Connective
Densely packed parallel collagen fibers and has compressed b
Fibroblast nuclei
Found in tendons and ligaments
Dense irregular connective
Densely packed randomly arranged collagen fibers and few visible cells
Withstands unpredictable stresses
Deeper layer of skin; capsules around organs
Adipose tissue
Empty looking cells with thin margins; nucleus pressed against cell membrane
Job: energy storage, insulation, cushioning
Hyaline cartilage
Usually covered by perichondrium
Eases joint movement, holds airway open, moves vocal chords during speech
Found in: articular cartilage, costal cartilage, trachea, larynx, fetal skeleton
Elastic cartilage
Cartilage containing elastic fibers
Covered with perichondrium
Provides flexible, elastic support
Found In: external ear and epiglottis
Fibrocartilage
Never has a perichondrium
Resists compression and absorbs shock
Found in: pubic symphysis, menisci, and intervertebral discs
Bone tissue (compact bone)
Osteocytes: mature bone cells that occupy the Lacunae
Osteon: structural unit in compact bone
Periosteum: tough fibrous connective tissue covering of the bone as a whole
Bone matrix
Blood Tissue
Fluid connective tissue
Transports cells and dissolved matter from place to place
Plasma
Bloods liquid ground substance
Formed elements in blood
Cells and cell fragments
Erythrocytes
Red blood cells
Transport O2 and CO2
Leukocytes
White blood cells
Defense against infection and other diseases
Platelets
Cell fragments involved in clothing and other mechanisms
Excitability
A characteristic of all living cells
Developed to highest degree in nervous and muscular tissues
Membrane potential
Electrical charge difference ( voltage ) that occurs across the plasma membranes is the basis for their excitation
Responds quickly to outside stimulus by means if changes in membrane potential
Nerves: changes result in rapid transmission of signals to other cells
Muscles: changes results in contraction, shortening of the cell
Nervous tissue
Specialized for communication by electrical and chemical signals
Consists of neurons and neuroglia
Skeletal muscle
Long threadlike cells - muscles fibers
Multiple nuclei adjacent to plasma membrane
Most attach to bone but also in tongue, upper esophagus, facial muscles, and some sphincter muscles (ring like or cuff like muscles that open and close body passages
It is voluntary ( conscious control over skeletal muscles
Cardiac muscle
Only in the heart
Contains one centrally located nucleus surrounded by light staining glycogen
Intercalated discs join cardiocytes end to end
Striated and involuntary ( not under conscious control)
Smooth muscle
Lacks stations and is involuntary
Propels content through an organ, regulates diameter of blood vessels
