A&P 4 lecture slides Flashcards
Define Biological Tissues
collections of specialized cells & cell products performing a specific function
What are the four principal types of biological tissues
Epithelial
Connective
Muscle
Nerve
What is the Epithelial tissue
layers of cells that covers exposed surfaces; lines internal passageways & chambers; forms glands
What is Connective tissue function
fills internal spaces, provides structural support for other tissues, transports material, stores energy reserves especially in the form of lipids, protects delicate organs, defend the body from invading microorganisms, surround and interconnect other types of tissues
What is Muscle tissue function
specialized for contraction and produces movement
What is Neural tissue function
carries information rapidly from one part of the body to another by electrical-type nerve impulses
What are glands
structures that produce fluid secretions (attached to or derived from epithelia)
What are the Epithelium characteristics
Cellularity: cells bound together by cell junctions
Polarity: upper parts and lower parts of cell has distinct structures and functions
Attachment: by means of a basal lamina (or basement membrane)
Avascular: no blood vessels
Regeneration: stem cells constantly replenish old and damaged cells
What are the functions of the Epithelial tissue
Physical Protection: from abrasion, dehydration, or damage from chemical or biological substances
Absorption: selective absorption and secretion
Sensation: large sensory nerve supply
Specialized Secretions: glandular epithelium secretes onto surface or interstitial fluid or the blood circulation
List the three types of cell junctions and their functions
Tight junctions - interlocking membrane proteins; no passage of H20 & solutes between cells (digestive tract)
Gap Junctions - interlocking channel proteins; ions and small molecules can pass (coordinate beating of cilia)
Desmosomes - durable interconnections of most epithelial cells; connection to underlying cytoskeleton (hold the epithelial cells of the skin together
Epithelial cells are held together by
cell adhesion molecules (CAMs). These are transmembrane proteins forming junctions between cells
Two major types of glands and their functions
Endocrine Glands: release secretions (hormones) the bloodstream Exocrine Glands: release secretions into special ducts & open to epithelial surface
Three modes of secretion and how they happen
Merocrine secretion: secretion is released from vesicles by exocytosis
Apocrine secretion: the top portion of the cell accumulates vesicles and then breaks down
Holocrine secretion: the entire cell is packed with secretory vesicles and then the cell bursts
the cell in nerve tissue that transmits impulses is
The neuron
cells that help protect, nourish and support neurons are called
neuroglia
most neural tissue is found in
the brain and spinal cord (control centers)
Main tissue involved in repairing damaged tissue is
connective tissue
The main cells involved repairing damaged tissue is
Mast cells
What are the two phases in repairing damaged tissue
1) Inflammation
2) Regeneration
What are the three types of muscle tissues
Skeletal Muscle tissue
Cardiac muscle tissue
Smooth muscle tissue
What are some characteristics of Skeletal Muscle tissue
Vertical striations
Many nuclei
Long cylindrical fibers
Voluntary
Has satellite cells which can divide to produce new muscle fibers if the fibers have been damaged
Where are Skeletal Muscle tissue located and what are their functions
It’s combined with connective tissues and nervous tissues in skeletal muscles
Function is to move or stabilize the position of the skeleton; guards entrances and exits to the digestive, respiratory and urinary tracts; generates heat; protects internal organs
What are some characteristics of Cardiac Muscle tissue
Short branched cells
Usually one nucleus
Limited repairing ability, repairs are incomplete
Vertical striations
Intercalated discs (special cell junctions) between cells
Involuntary
Where are Cardiac Muscle tissue located and what are their functions
Located in the heart
Functions to circulate blood; maintains blood (hydrostatic) pressure
What are some characteristics of Smooth Muscle tissue
Short and spindle shaped cells
No vertical striations
Single and central nucleus
Can regenerate if damaged
Involuntary
Characteristics: Common to all Connective Tissues
Main cells are spaced apart from each other and are not joined closely together
Extracellular Matrix is found in the space between cells which is made up of ground substance and protein fibers
What is ground substance in the extracellular matrix
the fluid, jell-like or hard substance surrounding cells
clear viscous and colorless (a syrupy substance)
What are protein fibers in the extracellular matrix
long strands of protein fibers in the ground substance (collagen fibers, elastin fibers, reticular fibers)
Three major types of connective tissues and their functions
Connective tissue proper: binds, packs, and fills tissues (Loose and Dense)
Fluid connective tissue: circulating connective tissue (Blood and Lymph)
Supporting connective tissue: supports and protects (Bone and Cartilage)
Cells contained in connective tissue
fibroblasts are most common - produces protein fibers two of which are elastin and collagen (very plentiful)
may contain macrophages - fight infection
adipocytes - store triglycerides (fat)
mesenchymal cells - stem cells that can turn into adipocytes, bone cells, or cartilage cells
melanocytes - pigment producing cells
mast cells - cause inflammation and regeneration of damaged connective tissue
What are the two fluid connective tissue
Blood fluid in cardiovascular system
Lymph fluid in lymphatic system
What does blood fluid contain
Plasma – watery medium/ground substance
Formed Elements:
Red blood cells (erythrocytes; RBC)
White blood cells (leukocytes; WBC)
Platelets
What is lymph
extracellular fluid found in the lymphatic vessels
Lymph fluid components
mostly lymphocytes, macrophages and microphages
Function of lymph
Maintains levels of nutrients, removes wastes, and toxins; maintains blood volume, alerts immune system to infections in body
What are the two connective tissue proper
Loose and dense
What are the two supporting connective tissues
Cartilage & Bone
Describe cartilages extracellular matrix
a firm gel (ground substance) with embedded protein fibers
What are cartilage cells and where are they found
Chondrocytes are cartilage cells found in lacunae
Fibrous layer surrounding cartilage is called
perichondrium
Three types of cartilage are
Hyaline cartilage
Elastic cartilage
Fibrocartilage
Hyaline cartilage location and function
Located between tips of ribs and bones of sternum; covering bone surfaces at synovial joints; supporting larynx, trachea and bronchi; forming part of nasal septum
Function is to provide stiff but somewhat flexible support; reduces friction between bony surfaces
Elastic cartilage location and function
Located in auricle of external ear; epiglottis; auditory canal; cuneiform cartilages of larynx
Function is to provide support but tolerates distortion without damage and returns to original shape
Fibrocartilage location and function
Pads within the knee joint; between pubic bones of pelvis; intervertebral discs
Functions to resist compression; prevents bone to bone contact; limits relative movement
Membranes function
membranes separate tissues and form barriers
What are membranes
are compound tissues (have both epithelial & connective tissue together)
Four types of membranes and their locations
mucous membrane; lines digestive, unrainy, reproductive and respiratory tracts. Is moist, secretes mucous
serous membrane: lines the body cavities
cutaneous membrane: cutaneous membrane is the skin
synovial membrane; lines a joint cavity & provides synovial fluid to nourish and lubercate cartilage
What is fascia
sheets of connective tissue mostly made of collagen lying beneath the skin. It stabilizes, encloses, and separates muscles and other internal organs
Adipose tissue location and function (loose connective)
Located deep in the skin; buttocks; breasts; padding around eyeballs and kidneys
It provides padding and cushions shocks; insulates; stores energy reserves
Reticular tissue location and function (loose connective)
Locates in the liver, kidney, spleen, lymph nodes and bone marrow
Provides supporting framework
Dense regular connective tissue location and function
Located between skeletal muscles and skeleton(tendons); between bones or stabilizing potions of internal organs(ligaments); covering skeletal muscles; deep fascia
Provides firm attachment; conducts pull of muscles; reduces friction between muscles; stabilizes relative position of bones
Dense regular elastic tissue (connective) location and function
Located between vertebrae of the spinal column; ligaments supporting penis; ligaments supporting transitional epithelia; in blood vessel walls
Stabilizes positions of vertebrae and penis; cushions shocks; permits expansion and contraction of organs
Dense irregular connective tissue location and function
Located in capsules of visceral organs; periostea and perichondria; nerve and muscle sheaths; dermis
Provides strength to resist forces applied from many directions; helps prevent overexpansion of organs such as the urinary bladder
What are the three simple epithelium
Simple squamous epithelium
Simple cuboidal epithelium
Simple columnar epithelium
What are the three stratified simple epithelium
Stratified squamous epithelium
Stratified cuboidal epithelium
Stratified columnar epithelium
Simple squamous epithelium location and function
Locates in the mesothelia lining ventral body cavities; endothelia lining the heart and blood vessel; portions of kidneys tubules; inner lining of the cornea; alveoli of lungs
Functions to reduce friction; controls vessel permeability; performs absorption and secretion
Simple cuboidal epithelium location and function
Located in the glands; ducts; portions of the kidney tubules; thyroid gland
Functions is limited protection, secretion, absorption
Simple columnar epithelium location and function
Located in the lining of the stomach, intestine, gallbladder, uterine tubers and collection ducts of kidneys
Function is protection, secretion and absorption
Also contains microvilli
Stratified squamous epithelium location and function
Located in the surface if the skin, lining of the mouth, throat, esophagus, rectum, anus and vagina
Function is to provide physical protection against abrasion, pathogens and chemical attack
Transitional epithelium location and function
Located in the urinary bladder, renal pelvis; uterus
Function is it permits expansion and recoil after stretching
Pseudostratified ciliated columnar epithelium location and function
Located in the lining of the nasal cavity, trachea and bronchi; portions of the male reproductive tract
Function is protection and secretion
Also contains cilia
