Chapter 5.2 : The Four Tissue Types Flashcards
What is tissue?
a group of similar cells
– arise from the same region of the embryo
– a tissue type has cells with similar structure and function
– tissue types work together to perform a specific physiological function within
an organ.
What are the four tissue types?
epithelial / muscle / nervous / connective
The four primary tissues differ from one another by
– function of their cells and the form of the matrix
– the type of the matrix (material made by cells and secreted outside of the cell’s plasma membrane) will determine the characteristic of the tissue.
– The ratio between cell and matrix volumes helps to define the tissue type // amount of space occupied by the cell and its matrix
Nervous tissue
Internal communication
- Brain
- Spinal cord
- Nerves
Muscle tissue
Contracts to cause movement
- Muscles attached to bones (skeletal)
- Muscles of heart (cardiac)
- Muscles of walls of hollow organs (smooth)
Epithelial tissue
Forms boundaries between different environments, protects, secretes, absorbs, filters
- Lining of digestive tract organs and other hollow organs
- Skin surface (epidermis)
Connective tissue
Supports, protects, binds other tissues together
- Bones
- Tendons
- Fat and other soft padding tissue
- Blood
- Fat
Epithelial forms the ____ and ______ of the body
forms the coverings and linings of the body
Muscle tissue is _______ & able to _____
excitable ; shorten
What are the types of muscle tissue
skeletal, smooth, cardiac
Connective tissue
most abundent & varied tissue type
Connective tissue types:
– Fibrous loose (areolar and reticular)
– Fibrous dense (regular or irregular)
– Fibroblasts – cell type
– Adipose – cell type
– Bone – a connective tissue type
– Blood – a connective tissue type
– Cartilage (hyaline / elastic / fibrous)
Nervous
excitable tissue & voluntary or involuntary
The four primary tissues differ from one another by
– function of their cells and the form of the matrix
– the type of the matrix (material made by cells and secreted outside of the cell’s plasma membrane) will determine the characteristic of the tissue.
– The ratio between cell and matrix volumes helps to define the tissue type // amount of space occupied by the cell and its matrix
matrix is composed of
“hydrated” fibrous proteins /// clear gel substance (the
“glue” that holds cells together)
Matrix also called:
- ground substance
- tissue fluid
- extracellular fluid (ECF)
- interstitial fluid
- tissue gel
apical
upper surface usually exposed to the
environment or an internal space in the body
basal surface
the part of the cell that attaches to the basement membrane
Epithelial Tissue make up most ___
glands
Epithelial Tissue is avascular
tissue allows no room for
blood vessels
Under the basement membrane of the epithelial tissue is ____
Loose connective tissue
provide blood vessels for nutrient procurement and
waste removal
Basal lamina
produced by epithelial cells
Reticular lamina
produced by fibroblast
diabetes mellitus
basement membrane thickens – this reduces diffusion
between dermis and epithelium
Basement membrane
matrix layer between epithelial tissue and the underlying connective tissue
anchors the epithelium to the connective tissue below it
Epithelial tissue has two “sides”
basal surface and apical surface
basal surface
surface of an epithelial cell that faces the
basement membrane
apical surface
surface of an epithelial cell that faces
away from the basement membrane
Simple epithelium
contains one layer of cells
– all cells touch the basement membrane
Stratified epithelium
– contains more than one layer
– named by shape of apical cells
– some cells rest on top of others and they do
not touch basement membrane
What is a goblet cell?
unicellular gland /// wine glass shaped mucus secreting cells found in simple columnar
and pseudostratified epithelia
Simple Squamous Epithelium
endothelium, and serosa
Simple Cuboidal Epithelium
bronchioles, and kidney tubules
Simple Columnar Epithelium
lining of GI tract
Pseudostratified Epithelium
respiratory tract
Stratified Epithelia (most widespread epithelium in the body)
cells resting directly on other cells
deepest layers undergo continuous mitosis
two kinds of stratified squamous epithelia
keratinized and nonkeratinized
keratinized
found on skin surface, abrasion resistant
nonkeratinized
lacks surface layer of dead cells (e.g. lining of
mouth and vagina)
Keratinized Stratified Squamous
Cutaneous membrane (i.e. skin)
Nonkeratinized Stratified Squamous
adult vagina, oral cavity, esophagus
* note: prior to puberty lining of vagina is simple nonkeratinized epithelium
Stratified Cuboidal Epithelium
sweat gland ducts
Transitional Epithelium
ureter and bladder
- multilayered epithelium surface cells that change
from round to flat when stretched - allows for filling of urinary tract
Four types of epithelial membranes
– cutaneous membrane (covered in Chapter 5)
– serous membrane (serosa)
– mucous membrane (mucosa)
– synovial membrane (not a true epithelial cell line)
Synovial membrane
lines joint cavities
cells which form this membrane are not epithelial but connective tissue cells
Mucous Membranes (The Mucosa) consists of three layers:
- epithelium
- lamina propria – areolar connective tissue
- muscularis mucosae – smooth muscle layer
Serous membrane (serosa)
internal membrane
simple squamous epithelium over areolar tissue
produces serous fluid that arises from blood
covers organs and lines walls of body cavities
What is a gland?
A gland may be a single cell or a group of cells
Glands releases substance onto a free surface (i.e.
exocrine) or into the blood (i.e. endocrine)
composed of epithelial tissue
merocrine glands
AKA eccrine
cell’s secretion delivered to surface by way of a
duct
endocrine glands
secretory product is a molecule which is
released into the blood
hormones
Cell’s secretory product / messenger molecule
unicellular glands
found in epithelium that is predominantly non-secretory tissue
– can be endocrine or exocrine
– mucus-secreting goblet or endocrine cells of stomach and small intestine
Goblet Cells Are ____Gland
Unicellular
Exocrine Gland Secretions
serous glands and mucous glands
Serous membranes secret things from tiny wholes like tears milk etc.
How do vfdc glands excrete their product.
How do Merocrine glands excrete their product. (AKA ____?)
Cell product excreted by exocytosis
How do Apocrine glands excrete their product.
pinches off part of the cells cytoplasm to release
secretion
How do Holocrine glands excrete their product.
Cells accumulate a product and then the entire cell disintegrates
Connective Tissue Has Many Functions. What are they
binding of organs, support, physical protection, immune protection, movement, storage, heat production, transport
Connective Tissue
binds organs to each other // support and protect organs
connective tissue cells usually occupy ___space than the
_____ material
less ; extracellular
Connective Tissue is the “highway” used by ___ to transit the human body (endoreticular system)
WBC
Connective Tissue are constructed by
cells, extracellular fibers, and matrix
fibroblasts
produce different types of fibers (e.g. collagen,
elastic, reticular) and ground substance
adipocytes
store triglycerides (fat molecules)
Collagenous fibers
most abundant of the body’s proteins –
25%
Connective Tissue Fibers
reticular fibers, elastic fibers,
Ground Substance
(part of the matrix / CT fibers embedded in GS)
Hyaluronic acid
a type of GAG
nicknamed - “the glue that holds our cells together”
loose connective tissue
either as areolar or reticular
dense regular
(tendons & ligaments)
dense irregular
(forms sheets which surround organs or structured
as 3D tissue as in the dermis)
Areolar CT (fibrous loose)
underlies all epithelia, between muscles
loosely organized fibers, abundant blood vessels, and a lot of
seemingly empty space
Reticular CT
stroma (framework) for lymphatic organs
Adipose Tissue
cushions organs
fat
white fat
stores energy
and used to make ATP for cellular work
brown fat
– in fetuses, infants, children – converted
directly into heat // not used to do cellular work
adipocytes
the dominant cell type
space between adipocytes is occupied by areolar tissue, reticular tissue, and blood capillaries
areolar tissue
fat is the body’s primary ____________ /// also provides ________
energy reservoir ; thermal insulation
Cartilage is produced by
chondrocytes
types of cartilage vary with fiber types
– hyaline cartilage
– fibrocartilage
– elastic cartilage
Does cartilage have blood vessels?
no
intercellular junctions
connections between cells
