Human Anatomy - Tissues

The four basic tissue types include?

epithelial, nervous, connective, and muscular

Epithelial Tissue

A body tissue that covers the interior and exterior surfaces of the body.

Nervous Tissue

A body tissue that carries electrical messages back and forth between the brain and every other part of the body.

Connective Tissue

A body tissue that provides support for the body and connects all of its parts

Muscular Tissue

Contracts and moves the various parts of the body.

Simple

One layer

Stratified

Layered

Squamous

Wide Cells, Example: lies blood vessels and lungs

Cuboidal

Cube shaped, Cells, Example: Lines kidney tubules

Columnar

taller than wide Cells, Example: Lines digestive tract

Pseudostratified

Single layer but some cells shorter than others, often looks like a double layer

Mitosis

Cell division

Internal Epithelial Tissue

Examples: Most Glands

External Epithelial Tissue

Skin, Hair, Fingernails, etc

Neuroepithelium

A type of epithelium that is specialized to perform a particular sensory function; these provide the senses

Exocrine Cells

made in cell and secreted

The Basement Membrane

The basal surface of epithelial tissue is connected to

Basal Lamina

thin extracellular layer that lies underneath epithelial cells and separates them from other tissues

Three major types or junctions

Tight juctions, Desmosomes junctions, Gap junctions

Tight Junctions

Membranes of neighboring cells are pressed together, preventing leakage of extracellular fluid

Demosomes

Junction that binds cells together by creating spot welds, on the outer skin

The structures within the heart tissue anchor individual cells together so they wont pull apart during contraction.

Gap Junctions

Points that provide cytoplasmic channels from one cell to another with special membrane proteins. Also called communicating junctions.

Transitional Epithelium

found in bladder, transitions from squamous to cuboidal, capable of stretching

Can be ...

Simple, Stratfied, Pseudo-Stratrified

Why would you find stratified squamous epithelium lining the esophagus?

To aid in movement of food through the lumen

apical surface

an upper free surface exposed to the body exterior or the cavity of an internal organ

Lumen

The inside of the a hollow organ (e.g., the somach, intestines, bladder, etc.) or a tube (e.g., blood vessels, ureters, etc.)

Glands

A cell, a group of cells, or an organ that produces a secretion for use elsewhere in the body or in a body cavity or for elimination from the body.

Merocrine glands

release by exocytosis; most exocrine glands are this type of gland. (salivary glands)

Holocrine glands

The cells in this type of gland rupture in order to make their secretions (Think Sebaceous glands)

Apocrine glands

-found in axillae, genetalia, ear canal

Sweat glands in the pubic and underarm areas that secrete thicker sweat, that produce odor when come in contact with bacteria on the skin

fibroblasts

Connective Tissue

Cells that secrete fibrous proteins which form a molecular network that holds tissue cells in place.

Common origin (mesenchyme)

an embryonic connective tissue

Connective Tissue Proper

Loose connective tissue. Adipose tissue, reticular connective tissue,

dense connective tissue and elastic connective tissue.

Supporting Connective Tissue

cartilage and bone

Fluid Connective Tissue

blood

Matrix

Non-cellular, fibrous material that ranges from solid -> liquid

Collagen fibers

provides flexibility and strength

Elastic fibers

If you gently bend your ear, and then let go, the shape of your ear will return because the cartilage of your ear contains_____.

Reticular Fibers

Fibers made of collagen fibers that are very thin and branched. Forma tightly woven fabric that joins connective tissue to adjacent tissues.

Functions of CT

Binds organs together, provides support and protection, fills spaces, produce blood cells, stores fat, other specialized stuff too, basically connective tissue connects stuff

Loose areolar connective tissue

Fills spaces and provides support, binds stuff together

Dense regular connective tissue

tendons, ligaments

Dense irregular connective tissue

Collagen fibers extending in many directions

found in deep portion of the skin and capsules around organs such as the liver, kidney, and spleen

Adipose tissue

Tissue that stores fat.

cartilage

A connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together.

chondrocytes

Cartilage cells

Lacunae

Small cavities in the bone or cartilage that hold individual bones or cartilage cells.

Why is healing slow from cells that are in chambers (Lacunae)

It is separated by a solid, flexible matrix that have no direct blood supply.

What are 3 example of Cells that are in chambers (lacunae)

Hyaline cartilage, Elastic cartilage, and Fibrocartilage

Hyaline cartilage

fetal skeleton, nose, ends of long bone, tracheal rings, etc

Elastic cartilage

Ear pinna or flap

Fibrocartilage

intervertebral discs, pubic symphysis, menicus

Bone

protects, provides support/movement, stores fat and minerals, produces ALL blood cells

Osteocytes

Bone cells

What is the most rigid CT and how?

Bone, very hard matrix of Ca++ slats for rigidity and collagen fibers for elasticity and strength

Blood

Liquid connective tissue, functions in transport and other stuff

Muscle tissue

A body tissue that contracts or shortens, making body parts move.

Contractile Proteins

Muscle tissue

Skeletal Muscles

muscles attached to bone that cause body movements

voluntary muscles

Smooth Muscles

involuntary muscle

muscles that act on the lining of the body's passageways and hollow internal organs

Cardiac Muscles

involuntary muscles

muscles found only in the walls of your heart

Muscle Cells

muscle fibers or

myocytes

Nervous Tissue

Function in Communications, Internally or Externally

Tissue that senses stimuli and transmits signals.

organs

Tissues are organized into:, group of tissues that work together to perform closely related functions.

histology

Study of tissues

epithelial tissue

A body tissue that covers the surfaces of the body, inside and out

epithelium

the cellular layer that covers external and internal surfaces

basement membrane

Cells at the base of an epithelial layer are attached to this.

simple

One layer

stratified

Layered

squamous

Scale-like Squished Cells

cuboidal

Cube shaped Cells

columnar

Tall and thin Cells

Pseudostratified Epithelium

-appears stratified (nuclei at different levels), but ALL cells sit on basement membrane = SIMPLE

Endocrine glands

Glands of the endocrine system that release hormones into the bloodstream

Exocrine Glands

secrete chemical substances into ducts that lead either to other organs or out of the body

Simple Squamous Epithelium

Function: Allows passage of materials by diffusion and filtration in sites where protection is not important; secretes lubricating substances in serosae.

Locations: Kidney glomeruli; air sacs of the lungs; lining of heart, blood vessels and lymphatic vessels; lining of ventral body cavity (serosae)

Simple Cuboidal Epithelium

Function: Secretion and absorption

Location: Kidney tubules; ducts and secretory portions of small glands; ovary surface

Simple Columnar Epithelium

Function: Absorption; secretion of mucus, enzymes, and other substances; ciliated type propels mucus (or reproductive cells) by ciliated action

LOCATIONS: Lining of stomach, intestine, gallbladder, uterine tubes, and collectin

Pseudostratified Columnar Epithelium

________ epithelium appears to have two or three layers of cells, but all the cells are in contact with the basement membrane.

Function: Secretes substances, particularly mucus; propulsion of mucus by ciliary action

Location: Nonciliated type in male;s sperm-carrying ducts and ducts of large glands' ciliated variety lines the trachea, most of the upper respiratory tract

Stratified Squamous epithelium

Function: protects underlying tissues in areas subject to abrasion.

Location: Nonkerantinized type forms the moist linings of the esophagus, mouth, and vagina; keratinized variety forms the epidermis of the skin, a dry membrane

Stratified Cuboidal Epithelium

Function: Protection

Location: Largest ducts of sweat glands, mammary glands, and salivary glands

Statified Columnar Epithelium

Function: Protection; secretion

Location: Rare in the body; small amounts in male urethra and in large ducts of some glands

Cartilage

A connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together.

bone

Mineralized connective tissue.

blood

A connective tissue with a fluid matrix called plasma in which red blood cells, white blood cells, and cell fragments called platelets are suspended.

loose connective tissues

Tissue that binds epithelia to underlying tissues and holds organs in place. Contains collagenous, elastic, and recticular fibers.

connective tissues

support and connect organs and other body tissues

dense regular connective tissue

Function: attaches muscles to bones or to muscles; attaches bones to bones; withstands great tensile stress when pulling force is applied in one direction

Areolar Connective Tissue

Most widely distributed connective tissue / Soft, pliable tissue / Contains all fiber types / Can soak up excess fluid

Loose connective tissue is also called

Adipose

Fat tissue

Extracellular matrix

Nonliving

The matrix is responsible for strength associated with connective tissue, but there is a variation in the amount of matrix.

The substance in which animal tissue cells are embedded, consisting of protein and polysaccharides.

Ground substance

fluid or semi-fluid portion of the matrix

reticular fibers

Fine Fibers made of collagen fibers that are very thin and branched. Forma tightly woven fabric that joins connective tissue to adjacent tissues.

Elastics fibers

Yellow Fibers

Collagen Fibers

provides flexibility and strength

Embryonic connective tissue: Mesenchyme

Function: Gives rise to all other connective tissue types

Location: Primarily in embryo

Connective tissue proper: Loose connective tissue, areolar

Function: Wraps and cushions organs; its macrophages phagocytize bacteria; plays important role in inflammation; holds and conveys tissue fluid

Location: Widely distributed under epithelia of body, e.g., forms lamina propria of mucous membranes; packages organs; surrounds capillaries

Connective Tissue proper: Loose connective tissue, adipose

Function: Provides reserve fuel; insulates against heat loss; supports and protects organs

Location: Under skin; around kidneys and eyeballs; within abdomen; in breast

Connective Tissue proper: Loose connective tissue, reticular

Function: Fibers form a soft internal skeleton (Stroma) that supports other cell types, including white blood cells, mast cells, and macrophages

Location: Lymphoid organs (lymph nodes, bone marrow, and spleen)