Tissues Flashcards
What are the four major types of tissues?
Epithelial, Connective, Muscle and Nervous
What is the main roles of epithelial tissue?
to form protective barrier and to function in secretion and absorption
describe the cell of a squamous tissue
thin and flat
describe the cell of a cuboidal tissue
a cube like shape
describe the cell of a columnar tissue
longer than wider, may have multiple nulcei
what is the free or open surface of the epithelial called
apical surface
the bottom of epithelial tissue is typically anchored to what?
connective tissue
What is the layer which connects epithelial tissue to connective tissue?
the basement membrane
describe the basement membrane
thin nonliving layer
what does the term “stratified” indicate?
that the epithelial tissues are composed of layers
How are epithelial tissues classified?
in terms of cell shape and number of layers in the tissue
describe simple squamous epithelium
a single thin flat layer of tissue, allows for some substances to pass through
Where would one find simple squamous epithelium?
lining the aveoli, lining blood cappilaries, lining blood and lymph vessels, covering membranes that line body cavity.
what is the function of simple squamous tissue?
to control diffusion, osmosis and filtration
describe simple cuboidal epithelium
a single layer of cuboid shaped cells
Where would you find simple cuboidal epithelium
Covering the ovaries and lines most of the kidney tubules and the ducts of certain glands
what is a function of simple cuboidal epithelium?
In the kidneys, this tissue functions in secretion and absorption; in glands, it secretes glandular products
describe simple columnar epithelium
Are longer than they are wide, Composed of a single layer of cells, Can be ciliated or non-ciliated
where is simple columnar epithelium found?
Found in uterus, portions of digestive tract, stomach and the small and large intestines
what is the function of simple columnar epithelium?
Secretes digestive fluids and mucus onto the free surfaces of tissue
describe pseudostratified columnar epithelium
Appear to be layered, or stratified but are not. Instead, the nuclei lie at two or more levels in the row of aligned cells, often contain goblet cells
what is the function of pseudostratified epithelium?
these secrete mucus while the cilia sweep dust and microorganisms away
where is pseudostratified epithelium found?
Lining the passages of the respiratory system
describe stratified squamous epithelium
made of thin flat cells that are layered the many cell layers that make this tissue relatively thick
where is stratified squamous epithelium found?
forms the outer layer of the skin, Lines the oral cavity, esophagus, vagina, and anal canal
describe stratified cuboidal epithelium
two or three layers of cuboidal cells
where is stratified cuboidal epithelim found?
Lines the larger ducts of the mammary glands, sweat glands, salivary glands, and pancreas
describe stratified columnar epithelium
Consists of several layers of cells, Superficial cells are columnar, whereas the basal layers consist of cuboidal cells
where are stratified columnar epithelium found?
Found in the male urethra and parts of the pharanx
What is the function of glandular epithelium?
to produce and secrete substances into ducts or into body fluids
Glands that secrete their products into ducts that open onto surfaces, such as the skin or the lining of the digestive tract, are called
excocrine glands
Glands that secrete their products into tissue fluid or blood are called
endocrine glands
What are the three main cell types of connective tissue?
fibroblasts, macrophages, mast cells
Most common type of fixed cell (resides in the tissue for an extended period of time) in connective tissue are
fibroblasts
What is the structure and function of fibroblasts?
Large, star shaped cells produce fibers by secreting proteins into the extracellular matrix of connective tissue
Originate as white blood cells and are almost as numerous as fibroblasts in some connective tissues
Macrophages
what is the function of macrophages
function as scavengers and defensive cells that clear foreign particles from tissues
what is the function of mast cells?
Mast cells release heparin, which prevents blood clotting, and histamine, which promotes some of the reactions associated with inflammation and allergies.
what are the three fibers of connective tissue?
collegenous, elastic, reticular
describe collogenous fibers
Are thick threads of the protein collagen, Grouped in long parallel bundles, and are flexible but only slightly elastic, but they have great tensile strength
where would you find collegenous fibers
primarily in tendons and ligaments
describe elastic fibers
Composed of a spring like protein called elastin, These fibers branch forming a complex network, Weaker than collagenous fibers
the vocal chords are made of what type of connective fibers?
elastic
describe reticular fibers
Thin collagenous fibers Highly branched and form delicate supporting networks
name one place where reticular fibers would be found
the spleen
what is a reason as to why older people may have wrinkles or saggy skin?
the sun decreasing its elasticity
What are three types of loose connective tissue?
Areolar, adipose and reticular
binds the skin to underlying organs and fills spaces between muscles.
Areolar tissue
cushions joints and some organs (such as the kidneys), and it also insulates beneath the skin and it stores energy in fat molecules
adipose tissue
helps provide the framework of certain internal organs, such as the liver and spleen.
reticular tissue
describe dense connective tissue
Often binds body parts in the form of tendons and ligaments. Blood supply to dense connective tissue is poor, slowing tissue repair.
found on the ends of bones in many joints, soft part of the nose and the supporting rings of the respiratory passages
hyaline cartilage
provides the framework for the external ears and for parts of the larynx.
elastic cartilage
is a shock absorber for structures that are subjected to pressure. For example, intervertebral discs, also cushions bones in the knees and the pelvic girdle.
fibrocartilage
what is the most rigid connective tissue?
Bone
What is the function of Bone?
Protects vital organs such as the brain, heart and lungs, Acts as an attachment site for muscles, Red marrow forms blood cells, Stores and releases calcium and phosphorus
form in red marrow within the hollow parts of certain long bones
Red blood cells
the function of red blood cells is
Transports material between interior body cells and those that exchange substances with the external environment.
what type of muscle tissue is voluntary?
skeletal
Found in the muscles that usually attach to bones
skeletal muscle
what causes a skeletal muscle to contract
stimulation from a nerve cell
where is smooth muscle found
Composes the walls of hollow internal organs, such as the stomach, intestine, urinary bladder, uterus, and blood vessels.
what is the function of smooth muscle?
moves food through the digestive tract, constricts blood vessels, and empties the urinary bladder.
Only found in the heart. Controlled involuntarily. Pumps blood through the heart chambers and into blood vessels.
Cardiac muscle
Found in the brain, spinal cord, and
peripheral nerves. Basic cells called neurons.
Nervous tissue
what is the function of nervous tissue?
Transmit electrical impulses along the cellular processes called “axons.” They coordinate, regulate, and integrate many body functions.
line joint cavities, only consist of connective tissue
synovial membrane
what is the basic structure of most membranes?
a layer of epithelial tissue bound to an underlying layer of connective tissue
what membrane makes up your skin?
the cutaneous membrane
describe the cutaneous membrane
consists of stratified squamous epithelium attached to a thick layer of dense irregular connective tissue. Exposed to the air and is dry
line body cavities that open to the exterior such as hollow organs of the digestive, respiratory and urogenital tracts these are moist and bathed by secretions
mucous membrane
moist membranes found in closed ventral body cavities. consist of simple squamous epithelium and loose connective tissue
Serous membrane
the function of mucous membrane
often adapted for absorption and secretion
most secrete mucous, though the urinary muscousa does not.
