KIN223 - CH5

Common features of ET

• Avascular, lacks blood vessels

• innervated

• very regenerative

• nutrients are received through apical surface

4 functions of ET

• physical protection

• selective permeability

• secretions

• sensation

Common features of ET

• Avascular, lacks blood vessels

• innervated

• very regenerative

• nutrients are received through apical surface

4 functions of ET

• physical protection

• selective permeability

• secretions

• sensation

What are the shape classifications of ET?

• Squamous — flat cells

• Cuboidal — cube shaped

• Columnar — skinny

• Transitional — changes shape

What are the layer classifications of ET?

• Simple — 1 layer of cells

• Stratified — 2 or more layers

• Pseudostratified — appears to be stratified, but all cells are secretly touching the basement membrane

Simple squamous ET

• 1 layer of flat cells

• allows for RAPID MOVEMENT, secretion and diffusion

• located in AIR SACS, VESSEL LININGS, SEROUS MEMBRANES

Simple cuboidal ET

• 1 layer

• made for ABSORBTION and SECRETION

• located in KIDNEY TUBULE LINING, DUCTS

Simple columnar ET

• 1 layer of cells

• made for SECRETION AND ABSORBTION

Non-ciliated simple columnar ET

• 1 layer of cells

• made to SECRETE GLYCOPROTEIN AND MUCOUS

  • located in GASTROINTESTINAL TRACT

Ciliated simple columnar ET

• 1 layer of cells

• Made to MOVE THINGS ALONG THE APICAL SURFACE

  • located in BRONCHIOLES AND UTERINE TUBES

Pseudostratified simple columnar ET

• 1 layer of weirdly shaped cells

Ciliated pseudostratified simple columnar ET

• 1 layer of cells with cilia on its surface

• made to trap foreign material moved by cilia

  • located in RESPIRATORY AIRWAY LININGS, NASAL CAVITY

Non-ciliated pseudostratified simple columnar ET

• 1 layer of cells, lacks cilia

• made to protect

  • located in MALE URETHRA LINING

Keratinized stratified squamous ET

• multiple layers of dead keratin

  • found in EPIDERMIS

non keratinized stratified squamous ET

• multiple layers of cells moist with secretions, lacks keratin

  • located in ORAL CAVITY, VAGINA, ANUS

stratified cuboidal ET

• 2 or more layers

• made for tubes and coverings

  • located in SALIVARY GLAND DUCTS, MEMBRANE LININGS OF PARTS OF MALE URETHRA

Transitional ET

• when relaxed, cuboidal basal cells and rounded apical cells

• apical cells are flattened when stretched

  • located in URINARY TRACT

What are glands?

Individual cells/multicellular organs made of ET, responsible for secreting substances in the body

Endocrine glands

Glands responsible for secretions INSIDE the body, typically into the blood

Exocrine glands

Glands responsible for secretions OUTSIDE of the body, they are invaginated with ET and are transported via ducts. (e.g. Mammary and sweat glands)

Gland classifications by SHAPE

• simple — single branched

• compound — branched ducts

• tubular — secretory and ducts are the same

• acinar — secretory portions form expanded sacs

• tubuloacinar — tubular and acinar combined

Gland classifications by SECRETION METHOD

• Merocrine — packaged into vesicles and released through exocytosis (e.g. sweat glands)

• Apocrine — apical end is pinched off and becomes a secretion (mammary gland)

• Holocrine — the cell EXPLODES

What are the 3 components of CT?

• Cells

• Protein fibers

• Ground substance

What are resident cells, give an example

• Resident cells remain stationary in the CT. They support, maintain, and repair the extracellular matrix (ECM)

  • FIBROBLASTS, ADIPOCYTES, MESENCHYMAL CELLS, FIXED MACROPHAGES

What are wandering cells, give an example

• Wandering cells continuously move through the CT and repair damaged ECM and protect from harmful agents

• Examples include types of white blood cells

What are the 3 protein fibers in CT?

• Collagen — cable-like fiber found in tendons and ligaments, has no stretch (thick cables on model)

• Reticular — similar to collagen fibers, thinner. Abundant in the stroma of some organs (looks like little hairs on model)

• Elastic — elastin protein, has stretch and recoil. Found in the skin and arterial walls (slightly thinner than collagen on model)

What are the 3 molecules that can be found in ground substance?

• Glycosaminoglycans or GAGS — large molecule, attracts cations, followed by water

• Proteoglycan — made with protein

• Glycoproteins — Protein + carb, bonds with the CT cells and fibers to the ground substance

What are the functions of CT?

PISSTB

• Physical protection

• Immune protection

• Storage of calories (adipose CT)

• Transport (blood)

• Support and binding of the structure (e.g. tendons and ligaments)

What is mesenchyme and mucous CT? What are their differences?

• Mesenchyme CT is the source of CT, with adult CT containing its stem cells. It is only found in the embryo body and fetus

• Mucous CT is only found in the umbilical cord

How does proper CT, support CT, and fluid CT differ from one another?

Proper CT makes up bodily structures, support CT helps support structures like bones, fluid CT helps deliver substances via blood to the other CT

What is loose CT? Which CT classify as loose?

• Loose CT has fewer cells and protein fibers, but plenty of ground substance

• acts as packaging peanuts, supports a structure

Areolar CT

• Consists of loose organization of collagen/elastic fibers, vascularized with prominent fibroblasts

  • located in — PAPILLARY DERMIS LAYER, SUBCUTANEOUS LAYER, NERVE AND MUSCLE CELLS, BLOOD VESSELS

Adipose CT

• Good for PIES — Protects, Insulates, Energy, Storage

• Makes up fat, adipose loss/gain is adipocytes growing or shrinking

• Has the white type and brown type

  • white stores energy, insulates, and cushions

  • brown generates heat for newborns, it is lost with age

  • located in — SUBCT LAYER, SURROUNDS AND COVERS SOME ORGANS

Reticular CT

• a meshwork of reticular fibers, fibroblasts, and leukocytes, visually appears as metal frames

  • located in — SPLEEN AND THYMUS

What is dense CT? Name the dense CT

• Dense CT has more fibers and less ground substance, with some amount of collagen fibers

• Dense regular/irregular

• elastic

Dense regular CT

• Tightly packed cells that run parallel, with stress being applied in one direction (perpendicular cuts result in longer healing time)

• few blood cells in it

  • located in — TENDONS AND LIGAMENTS

Dense irregular CT

• Provides resistance in multiple directions, with clumps of collagen fibers

  • located in — DERMIS, EPIMYSIUM, ORGAN CAPSULES

Elastic CT

• Densely packed branching fibers that have stretch and recoil

  • located in — LARGE ARTERIAL WALLS, TRACHEA, VOCAL CORDS

What is supporting CT? Name supporting CT

• Firm, semisolid ECM, cartilage

• made up of collagen and elastic protein fibers , with chondrocytes living in mature cells

• Hyaline cartilage

• Fibrocartilage

• Elastic cartilage

Hyaline cartilage

• Has a clear, glassy appearance under the microscope

  • located in — NOSE, TRACHEA, RIBS, ARTICULAR ENDS OF LONG BONES, FETAL SKELETON

Fibrocartilage

• Weightbearing cartilage, containing more protein fibers

  • located in — INVERTEBRAL DISCS (THE SPINE), PUBIC SYPMHYSIS, MENISCI OF KNEE JOINT

Elastic cartilage

• a more flexible cartilage, has more spring

  • located in — EXTERNAL EAR, EPIGLOTTIS

Bones

• contain collagen and glycoproteins

Osteocyte

Cell located in the lacuna in bone matrix

Osteon

Functional unit of compact bone tissue,

Osteoblasts

Help form new bones, grows and heals existing bones. blast = build

Osteoclast

Dissolves and breaks down old or damaged bone cells

Smooth muscle

• Visceral/involuntary, lacks striations

• spindle spindle shaped, or fusiform

  • located in — INTESTINE WALLS, STOMACH, AIRWAYS, BLADDER

Skeletal muscle

• voluntary, has alternating light-dark striations of long skeletal muscle fibers arranged in bundles

• responsible for moving the skeleton

  • located in — BONE ATTACHMENTS, URETHRAL AND ANAL SPHINCTERS

Cardiac muscle

• involuntary (obviously), contains visible striations and are connected via intercalated discs, promoting rapid conduction

• shaped like Y’s

  • located in — HEART WALL, MYOCARDIUM

Nervous tissue

• neurons, processes nerve impulses, supported by GLIAL CELLS

• Dendrites RECEIVE

• Axons take OUT

Organ

A group of tissues working together with one function, The heart is made up of cardiac tissues

Mucous membranes

• membranes exposed to external environment

• responsible for absorption, protection, and secretion

  • located in — DIRESTIVE, RESPIRATORY, URINARY, REPRODUCTIVE SYSTEMS

Serous membranes

• located in the internal environment

• surrounded by simple squamous ET

• makes SEROUS FLUID, reducing friction between opposing surface, aslo creating parietal and visceral layers

• serous cavity between

Cutaneous membrane

• the skin, covering external surfaces

Synovial membrane

• areolar CT, squamous ET

• contains synovial fluid, reducing friction and distributing nutrients

What are the 3 germ layers, and the tissues they give rise to

• Ectoderm — the skin

• Mesoderm — skeletal muscles, smooth muscle, blood vessels, bone, cartilage, joints, connective tissue, endocrine glands

• Endoderm — lung, liver, stomach, intestine, colon, pancreas, bladder, and thyroid

Hypertrophy

Cell increases in SIZE

Hyperplasia

Cell increases in NUMBER

Atrophy

Tissue SHRINKS

Metaplasia

Mature ET changes to a different form

Dysplasia

Abnormal tissue development, precancerous, though it's possible for it to revert back.

Neoplasia

Abnormal growth of cells

Necrosis

Tissue death

What is a way tissues are affected by age

Less collagen