Topic 4 = Histology

Voluntary

Conscious control over skeletal muscles. Found attached to bones.

Endocrine

Have no ducts; secrete hormones directly into blood

Mast cells

Secrete heparin to inhibit clotting. Secrete histamine to dilate blood vessels.

Striated muscular tissue

Alternating dark and light bands

Axon (nerve fiber)

Sends outgoing signals to other cells, Can be more than a meter long

Adipose tissue function

energy storage, insulation, protective padding

pseudostratisifed columnar epithelial tissue location

lines nasal cavity, trachea, bronchi, male reproductive ducts

dense irregular tissue function

multidirectional tensile strength

Dendrites

multiple short, branched processes, receive signals from other cells, transmit messages to neurosome

Apocrine

musky smell, in axillary and genital region

desmosomes

patch that links a cell to a neighboring cell. ties into the cytoskeletal system

necrosis

pathological tissue death due to trauma toxins or infections

apoptosis

programmed cell death, normal cellular process

Hypertrophy

enlargement of preexisting cells

areolar tissue function

"packing peanuts," stores fluids, immune surveillance

What is the outer embryotic tissue called?

Ectoderm

Areolar tissue location

underlies most epithelial, surrounds blood vessels, nerves, and visceral organs

stem cells

undifferentiated cells, can divide repeatedly, can produce one or more cell types,

Elastic tissue location

walls of large arteries, vocal cords

phase 3 of wound healing

week 1-6 proliferation, pulls the wound closed

phase 4 of wound healing

week 6 to 2 years remodeling, final proper tissue

what is meant by stratified

2 or more layers of cells

Recticular

A supporting mesh in soft tissues such as liver, bone marrow, and the tissues and organs of the lymphatic system

Hemidesmosomes

Anchor epithelial cells to a basement membrane

Elastic

Are extracellular components of higher vertebrates and confer elasticity and resilience to numerous tissues and organs such as large blood vessels, lungs, and skin

When looking at the stratified tissues, which cell layer determines the name, basal or apical?

By the shape of the most apical layer of cells, closets to the free space.

Unicellular

Can be exocrine or endocrine.

Multicellular

Capsule, stroma, parenchyma.

Chondrocytes

Cartilage cells that are trapped in lacunae (cavities).

Glands

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

Holocrine

Cells accumulate a product until they "burst" Secrete a mixture of cell fragments and synthesized substances Examples: oil glands of scalp and skin, and glands of eyelids

UnStriated muscular tissue

Cells are elongated, cells are not branched.

What is the inner embryotic tissue called?

Endoderm

Keratinized and nonkeratinized Stratified squamous Location

Epidermis, Tongue, oral mucosa, esophagus, and vagina

Involuntary

Found in the walls of internal organs.

Proteoglycans

Gigantic molecules (core protein plus GAGs) shaped like bottle brushes. Form gravy-like colliods that hold tissues together.

cell body (neurosoma)

Houses nucleus and other organelles, controls protein synthesis

where would you find stem cells

In the basal layer of the epidermis

Serous membrane (serosa)

Internal membrane. Function- Produces serous fluid that arises the blood.

Mucous membrane (mucosa)

Lines passages that open to the external environment (example: digestive tract). Sublayers: epithelium, lamina propria (areolar tissue), muscularis mucosa (smooth muscle). Function- Absorptive,secretory, and protective functions.

Exocrine

Maintain their contact with surface of epithelium by way of a duct.

What is the middle embryotic tissue called?

Mesoderm

Macrophages

Phagocytize foreign material and activate immune system.

Fibroblast

Produce fibers and ground substance of matrix.

secretion

Product useful to the body.

Neuroglia (or glial cells)

Protect and assist neurons,"Housekeepers" of nervous system, *More numerous than neurons*

Stratified squamous (keratinized and nonkeratinized)- function

Protection against microorganisms from invading underlying tissue and/or protection against water loss

Adhesive glycoproteins

Protein-carbohydrate complexes. Bind component tissue together

Cutaneous membrane (The skin)

Relatively dry layer serves protection.

Glycosaminoglycans

Responsible for stiffness of cartilage.

Adipocytes

Store triglycerides (fat molecules)

skeletal muscle tissue

Striated, multinucleated, voluntary

Plasma cell

Synthesize antibodies(proteins)

Collagen

The fiber in the extracellular matrix of connective tissues characterized by being elongated and made up of collagen glycoproteins.

Osteocytes

They allow for nutrients and transfer between cells through gap functions.

excretion

Waste product.

Leukocytes

White blood cells.

transitional epithelium function

allows the organ to stretch; protects underlying tissue

what is the basement membrane

basal lamina and reticular lamina

what are the four stages of wound healing?

bleeding, inflammation, proliferation, remodeling

bone tissue location

bones

metaplasia

changing from one type of mature tissue to another

Hormones

chemical messengers that stimulate cells elsewhere in the body

epithelial tissue characteristics

closely packed cells, covers body surfaces and lines body cavities, have a free upper surface, avascular, usually nourished by underlying connective tissue, have a high rate of mitosis

phase 1 of wound healing

day 1-3 hemostosis

phase 2 of wound healing

day 3-20 inflammation, new framework for blood vessel growth

dense irregular tissue location

deep part of the dermis, fibrous capsules of organs and joints, fibrous sheaths of bones, nerves, and many cartilages

Neurons (nerve cells)

detect stimuli, respond quickly, and transmit coded information rapidly to other cells

Elastic cartilage location

ear, epiglottis

elastic tissue function

elasticity

does the endocrine or exocrine system secrete directly into the bloodstream?

endocrine

stratified squamous epithelium location

epidermis (heavily keratinized); oral cavity, esophagus, vagina (non-keratinized)

the 4 classes of tissues

epithelial, connective, muscle, nervous

does the endocrine or exocrine system use ducts

exocrine

matrix

fluid/gel-like, mesh of reticular fibers

hyperplasia

growth through cell multiplication

blood connective tissue location

heart and blood vessels

Adipose tissue location

hypodermis, surround organs, yellow bone marrow, fatty deposits

Fibrocartilage location

intervertebral discs, some joints, pubis symphysis

smooth muscle tissue

invoulintary, not striated, fusiform, large nucleus, smaller than the other 2 muscle tissues

Simple Cuboidal epithelial tissue Location

kidney tubules, small ducts and glands

Simple Columnar epithelial tissue Location

lines the digestive tract, uterus, uterine tubules, small bronchi, ducts of large glands

Simple squamous epithelial tissue location

lines the heart and blood cells, air sacs of lungs, serous membranes

Transitional epithelial Location

lines the urinary bladder, ureters, urethra

merocrine or eccrine glands

located over entire body; empty on the skins surface, temperature regulation

what is meant by pseudostratified

looks multilayered, but all cells touch basement membrane

Reticular tissue location

lymph nodes, spleen, thymus, bone marrow

bone tissue function

mineral storage, protects organs, attachment sites for muscles

Hyaline cartilage location

most of respiratory tree, articular cartilage, nose, costal cartilage, developing bone

simple columnar function

often have microvilli to increase surface area or cilia to create a current

what is meant by simple

one layer of cells

gap junctions

pore made up of 6 transmembrane proteins. allow ions, nutrients and other small molecules to move between the cells

epithelial tissue common functions

protect deeper tissues from injury and infections, produce and release chemical secretions, excrete wastes, absorb chemicals including nutrients, selectively filter substances, sense stimuli

stratified squamous epithelium function

protection of underlying tissues from abrasion; slows water loss

elastic cartilage function

provides support, very flexible

Hyaline cartilage function

provides supportive framework

Dense regular connective tissue function

provides unidirectional tensile strength

simple squamous function

rapid diffusion, secrets serous fluid

tight junctions

seals off intercellular space making it difficult for substances to pass between cells. forces materials to travel through the cell = acts as a cell

pseudostratisifed columnar epithelial tissue function

secretes and moves mucus via cilia

simple cuboidal function

secretion and absorption

fibrocartilage function

shock absorption

atrophy

shrinkage of a tissue through a loss in cell size or number

nervous tissue common functions

specialized for communication by electrical and chemical signals, Changes in voltage result in rapid transmission of signals to other cells

cardiac muscle tissue

striated, intercalated discs, one huge centrally located nuceli, voluntary

reticular tissue function

supportive framework for lymphatic organs

Dense regular connective tissue location

tendons, ligaments

blood connective tissue function

transports nutrients, hormones, gases, waste, etc.

tissue sections

transverse, longitudinal, oblique

connective tissue common functions

•Connecting organs—tendons and ligaments •Support—bones and cartilage •Physical protection—cranium, ribs, sternum •Immune protection—white blood cells attack foreign invaders •Movement—bones provide lever system •Storage—fat, calcium,phosphorus •Heat production—metabolism of brown fat in infants •Transport—blood

connective tissue characteristics

•Diverse, abundant type of tissue •Lots of space and material (matrix) outside of the cells •Most cells are not in direct contact with each other •Highly variable vascularity •Loose connective tissues have many blood vessels •Cartilage has few or no blood vessels

muscular tissue characteristics

•Elongated cells that are specialized to contract in response to stimulation •Changes in voltage result in contraction, shortening of the cell •Three types of muscle: skeletal, cardiac, and smooth

Muscular Tissue: common functions

•Primary job is to exert physical force on other tissues and organs •Creates movements involved in body and limb movement, digestion, waste elimination, breathing, speech, and blood circulation •Important source of body heat