Chapter 4 Tissues

Four Tissue Types

Epithelial

Connective

Muscle

Nervous

Cell Junctions

contacts points between plasma membranes of tissue cells

What are the parts of cell junctions

tight junctions

gap junctions

adherens junctions

desmosomes

hemidesmosomes

Protein Belts

extend between 2 neighboring cells

Tight Junctions

prohibit passage of substances between cells and prevent contents of certain organs from leaking

found in the stomach intestines, and urinary bladder

Gap Junctions

gap between cells - allows cells to communicate

seen in nerves and muscles allowing impulses to spread

found in the heart, GI Tract, and Uterus

Neurons

Adherens Junction

help epithelial surfaces resist separation during contractile activities

when good moves through the intestines

contain plaque

Desmosomes

similar to adherens junctions prevent epidermal cells from separating under tension and cardiac cells from pulling apart during contraction

Hemidesmososmes

these anchor cells to the basement membrane not to each other

Epithelial Cells rest

on the Basement Membrane

The Two layers of an epithelial cells are

the basal lamina and the reticular lamina

Epithelial Tissue classifications

either simple(one layer) or stratified (two or more layers)

shape:

squamous, cuboidal, columnar

Simple

diffusion, osmosis, filtration, secretion, absorption

no wear and tear

Psuedostratified

secretion, movement of substances

Stratified

found where there is wear and tear

Simple Squamous Location

blood and lymphatic vessels, lungs

Simple Squamous Function

absorption of gasses, filtration of toxins, secretions

Stratified Squamous (nonkeratinized) Location

surface/lining of the mouth, esophagus, and vagina

Stratified Squamous (nonkeratinized) Function

protection

Stratified Squamous (keratinized) Location

surface of the skin

Stratified Squamous (keratinized) Function

protection

Transitional Location

urinary bladder and ureters

Transitional Function

permits stretching

Transitional

two to three layers thickness to 5-6 depending on the movements

like bladder

Cilia

tiny hairs on columnar

velcro allows cilia to move

moves it back if something has gone too far

Mucus

traps reticular matter

cilia cleans it up

Simple Columnar Location

lining of the stomach, intestines, and respiratory tract

Simple Columnar Function

secretion, absorption, protection, movement

Pseudo-stratified Columnar Location

vas deferens

trachea

bronchi

some glands

Pseudo-stratified Columnar function

protection

Simple Cuboidal Location

kidneys, ducts and tubules of many organs

Simple Cuboidal Function

absorption, secretion

Connective Tissues

most abundant of the tissues

binds, supports, strengthens, protects, insulates, transports, stores, major immune response

Basic Elements of CT

Cells

Extracellular Matrix

Fibers

Cells

fibroblast, Macrophages, plasma cells, mast cells, adipocytes, WBC’s (white blood cells)

Fibroblasts

produce fibers

Macrophages

pacman, eats bacteria

Plasma Cells

produce antibodies

blood cells

Mast Cells

Stationary (don’t move)

Adipocytes

Fat cells

Extracellular Matrix

contain glycosaminoglycans, hyaluronic acids(gelantinous)

Fibers

collagen(thick), elastic(thick but gives elasticity ), reticular(thinner than collagen)

Connective tissue CLassifications

Loose CT, Dense CT, Cartilage, Bone, Liquid CT

Loose Connective Tissues

not a lot of fibers

adipose (fat cells)

reticular

Dense Connective Tissue

A lot of fibers

Dense regular (nice neat orderly)

Dense irregular (all over)

Cartilage

Hyaline (reponsible for formation of the bone)

fibrocartilage

elastic

Bone

built using hyaline cartilage

Liquid CT

Blood

Lymph

Erythrocytes

transports gases O2 and CO2

Lucacytes

white blood cells

immune system

Thormacyte

platelites - not a cell

ameacarriecyte

Connective Tissue Proper Loose

Fibers create a loose, open framework

ex: areolar tissue

adipose tissue

reticular tissue

Connective Tisue Proper Dense

fibers densely packed

ex: dense regular

dense irregular

elastic

Fluid Connective Tissues Blood

contained in cardiovascular system

Fluid Connective Tissues Lymph

contained in lymphoid system

Supporting CT Cartilage

solid, rubbery matrix

ex: hyaline cartilage

elastic cartilage

fibrous cartilage

Supporting CT Bone

solid, crystalline matrix

Embryonic CT Contains

Mesenchyme Tissue

Whartons Jelly

Mesenchyme Tissue

found exclusively in the embryo and is where all of the other CT arise

Whartons Jelly

(mucous CT) found in the umbilical cord

Muscle Tissue

Smooth tissue

Skeletal Tissue

Cardiac Tissue

Smooth Muscle Tissue

involuntary (not something we can control), non-striated, single nucleated cell

Skeletal Muscle Tissue

Voluntary (can be controlled), striated, multi-nucleated

Cardiac Muscle Tissue

involuntary, striated, may contain between 0-3 nuclei (withing specific cardiac muscle cell)

branched uninucleated fibers

Cardiac Muscle Tissue occurs

in the walls of the heart

Skeletal Muscle attaches

to skeleton

Smooth Muscle Tissue occurs

in walls of internal organs

Smooth Muscle Tissue is autonomic T/F

T

Autonomic Smooth Muscule Tissue is foun

digestive tract

uterus

reproductive tract

controlled by hormone, oxytocin

Nervous tissue

Neurons

Neuroglial Cells

Neuroglial cells

do not conduct impulses

supporting for the neurons

What do the Neuroglial cells do

bring in the protein

gets rid of waste

immune function

What can a Neuroglial cell be used for?

to protect the brain and brain barrier

Example of the Glial Cell Line

Astrocytes (form blood-brain barrier)

Blood-brain barrier

protects the brain from blood-born pathogens

like an astrocytoma (brain tumor)

Does mitosis occur in Neuroglial cells

yes

Does mitosis occur in neurons

no

Neurons

convert stimuli into action potentials

Neurons contain

Sensory

Interneurons

Motor

Sensory Neurons

appropriate stimulus is needed to be activated

Sensory Receptors

temperature

pressure

touch

Touch - Sensory Receptor

course touch (tell you you’re touching something)

fine touch (better understanding of what you’re touching)

Intreneurons

only found in the central nervous system

tells the brain about the pain

Motor Neurons

gets messages of pain

takes the action

Glands

secretes a substance

How are glands classified

classified according to whether the ducts are branched or not and the shape of the secretory portions of the glands

Type of glands

Exocrine

Endocrine

Exocrine

glands with ducts

secrete mucus, sweat, saliva, digestive enzymes

Endocrine

ductless glands

secrete hormones

something produced in one part of the body that is used across a long distance

Endocrine Examples

pituitary, thyroid, adrenal, and pineal

The Pancreas is what gland, endocrine or exocrine

it is both

Exocrine Examples

sudoriferous, salivary, and the single-celled goblet cell

If duct is not branched

simple

if duct is branched

compound

Simple/Compound pictures can be:

tubular, coiled tubular (simple), acinar, branched acinar, and tubuloacinar

Functional Classification of Glands

Merocrine

Apocrine

Holocrine glands

Merocrine

secretions are released in secretory vesicles via exocytosis

Merocrine is seen in

salivary gland, pancreas, etc

Apocrine

secretory product accumulates at the apical surface of the cell then pinches off from the cell to release the product

the remaining cell repairs and repeats the process

Apocrine is seen in

mammary glands