Chapter 5 AP1 notes

Tissue

A group of similar cells and cell products working together to perform a specific role in an organ.

Matrix

Composed of fibrous proteins, it is also known as Tissue fluid, ECF, or interstitial fluid.

Ground Substance

A clear gel that is used to describe the matrix.

Ectoderm

Outer germ layer that gives rise to the epidermis and nervous system

Endoderm

The inner germ layer that is the mucous membrane lining, digestive tract lining and others.

Mesoderm

the middle germ layer of wispy collagen fibers and fibroblasts in the gel matrix giving rise to cartilage, blood, and bones.

Mesenchyme

The gelatinous tissue the mesoderm becomes.

Histological Sections

Tissue sliced into thin sections one or two cells thick in a fixative formula to prevent decay and staining it for better view.

Longitudinal section

Tissue cut on the long axis

Cross Section

tissue cut perpendicular to the long axis of the organ.

Oblique Section

Tissue cut at an angle between cross and longitudinal sections

Smear

Tissue is rubbed or spread across a slide (blood or soft tissue).

Spread

Tissues are laid out on a slide (membrane or cobweb like tissues).

Epithelial tissue

Sheet of closely adhering cells with their upper surface exposed to the environment, high mitosis rate and is avascular meaning it does not have blood vessels (found on body surfaces and the lining of the body cavity).

Functions of the Epithelial Tissue

Main tissue that is used to protect, secrete, excrete, absorb, filtration, and sensation.

Basement Membrane

Layer between an epithelium and underlying connective tissue.

Simple Epithelial Tissue

One layer of cells that is anchored to the basement membrane.

Stratified Epithelial tissue

where the tissue cells are on top of other tissue cells and not intact at all with the basement membrane.

Pseudostratified columnar epithelial

not all cells reach the surface but it is not stratified since all the cells touch the basement membrane.

Goblet cells

Wineglass shaped mucus secreting cells in the simple columnar and pseudostratified epithelial.

Simple Squamous Epithelial

Line look formation of flat cells, rapid diffusion tissue that secretes serous fluid located in the alveoli, glomeruli (kidney capsules), endothelium (Lining of blood vessels), and serosa (layer to the organs).

Simple Cuboidal Epithelial

Ring

Simple Columnar Epithelial

Tall stretched formation of rectangular cells used for absorption and secretion, there is also a brush border of microvilli and it can be found in the lining of the GI tract, uterus, kidney, and uterine tubes.

Pseudostratified columnar Epithelial

Multilayer formation but all the cells touch the basement membrane for secretion and propulsion of mucus, it is the only tissue with cilia in the human body and has goblet cells, it can be found in the respiratory tract and parts of the male urethra.

Keratinized Stratified Squamous Epithelial

Multiple layer cell formation made of keratin that resists abrasion and penetration, it is found on the epidermis, palms, and soles of your feet.

Nonkeratinized Stratified Squamous Epithelial

Does not have a surface layer of dead cells that resist abrasion and pathogen penetration, it can be found on the tongue, oral mucus, esophagus, and vagina.

Stratified Cuboidal Epithelial

Layered cube cell formation that is used for the secretion of sweat, production of sperm, and ovarian hormonal production. It can be found in sweat glands, ovarian follicles, and seminiferous tubules.

Urothelium

Multilayered epithelium with a surface that can change shape to stretch allowing more fluid in, it can be found in the ureter and bladder.

Connective Tissue

Most abundant and widely distributed tissue which are not in direct contact with each other that are highly variable in vascularity used for binding, movement, storage, heat, transport, support, protection, and immunity.

Fibroblasts

Produce fibers and ground substance in the matrix.

Macrophages

Arise from monocytes and phagocytize foreign material and activate immune system.

Leukocytes

Function in immune defense.

Plasma cells

Synthesize antibodies.

Mast cells

Secrete heparin to inhibit clotting and histamine to dilate blood vessels

Adipocytes

clustered in some fibrous proteins.

Collagenous fibers

Tough flexible and resistant tissue that are found in tendons, ligaments, and deep layers of the skin.

Reticular fibers

Thin collagen fibers that form the framework of the spleen and lymph nodes and are part of the basement membrane.

Elastic Fibers

Thin collagenous fibers made of the protein elastin that stretch and recoil like a rubber band.

Glycosaminoglycans

long polysaccharide composed of amino sugars and uronic acid that regulate water and electrolyte balance.

Proteoglycans

Giant bottle brush shaped molecules that form gravy like colloids that hold tissues together.

Adhesive glycoproteins

Protein carbohydrate complexes that bind components of the tissue together.

Loose Connective Tissue

Mostly ground substance in the space surrounding the cells (areolar and reticular).

Dense Connective Tissue

Mostly fibers in space surrounding the cells (Dense regular and Dense irregular).

Areolar tissue

Loosely organized fibers that are abundant in blood vessels, it underlies the epithelia and it is found almost everywhere since it connects tissues to other tissues.

Reticular Tissue

Mesh of reticular fibers and fibroblasts and forms a supportive framework for lymphatic organs (bone marrow, spleen, thymus, and lymph nodes).

Dense Regular Connective Tissue

Densely packed, parallel collagen fibers that are elastic and sheeted that are found in tendons and ligaments.

Dense Irregular Connective Tissue

Densely packed and randomly arranged collagen fibers that are extremely strong, it is found in the dermis layer and the capsules around your organs.

Adipose Tissue (fat)

tissue in which adipocytes are the dominant empty looking cell type that serves as the reservoir for fat.

Cartilage

Avascular, stiff connective tissue with a flexible and rubbery matrix that can be found in our nose, ears, and larynx.

Chondroblast

Cartilage cells that produce the matrix.

Chondrocytes

Cartilage cells that are trapped in lacunae (cavities).

Perichondrium

Sheath of dense irregular connective tissue that surrounds elastic and most hyaline cartilage.

Hyaline Cartilage

Clear glassy collagen cartilage that eases joint movement, it can be found in the articular cartilage, costal cartilage, trachea, larynx, and your fetal skeleton.

Elastic Cartilage

Large looking cells covered with perichondrium that provides elastic support found in your outer ear and epiglottis.

Fibrocartilage

Small cells with large coarse bundles of collagen bundles that resists compression and absorbs shock, it is found in the pubic symphysis, menisci, and intervertebral discs.

Spongy Bone

Delicate silvers and plates give it a spongy appearance found in the heads of long bones and in the middle of flat bones.

Compact bones

Denser calcified tissue with no visible space found on the surfaces of all bones with osteonic canals that nerve and blood vessels travel through.

Erythrocytes

Your red blood cells that transport oxygen and carbon dioxide

Leukocytes

your white blood cells that defend against infection.

Platelets

Cell fragments involved in clotting.

Excitability

Ability to respond to stimuli by changing membrane potential like muscle and nerve tissue.

Nervous Tissue

Specialized for communication by electrical and chemical signals.

Neurons

Detect stimuli and respond quickly to transmit information to other cells.

Neuroglia

Protect and assist neurons and are the housekeepers for the nervous system.

Cell Body

Houses the nucleus of a neuron that controls protein synthesis.

Dendrites

Short branched processes that receive signals from other cells.

Axon

Sends outgoing signals to other cells that can be more than a meter long.

Muscular tissue

Specialized to contract when stimulated, exerting a physical force on other tissues, organs, or fluids (Skeletal, cardiac, smooth).

Skeletal muscle

Attached to bones, they are made on long thin and fibrous cells and contain multiple nuclei that contract voluntarily.

Striations

alternating dark and light bands.

Voluntary

conscious control over skeletal muscles.

Cardiac Muscle

Limited to only the heart wall, they look branched, are striated, and it involuntarily contracts.

Smooth Muscle

Made of short fusiform cells with one central nucleus, it is found in the walls of your hollow organs and most of it is involuntary visceral muscle.

Cellular Junction

The connections between two cells.

Gland

Cell or organ that secretes substances for use elsewhere in the body or releases them for elimination from the body.

Secretion

releasing products useful to the body.

Excretion

Releasing waste from the body.

Exocrine Gland

Maintain their contact with the surface of the epithelium by the way of a duct like your sweat, tears, saliva.

Endocrine Gland

Have no ducts but do have many blood capillaries that secrete hormones directly into blood found in your thyroid, adrenal, and pituitary glands.

Hormones

Chemical messengers that stimulate cells elsewhere in the body.

Unicellular gland

Secretory cells found in an epithelium that is predominantly non secretory, it can be exocrine or endocrine and found in mucus goblet cells or endocrine cells in the stomach.

Serous Glands

Produce thin watery secretions like milk, tears, and digestive juices.

Mucous Glands

Produce glycoprotein called mucin which absorbs water to form mucus.

Mixed Glands

Contain both serous and mucous cell types and produce a mixture of two kinds of secretion like the two pairs of salivary glands in the chin.