A&P Exam 2

four types of tissue

epithelial, connective, muscle, nervous

functions of epithelial tissue

protection, permeability, sensation, secretions

characteristics of epithelia

polarity (apical and basal surfaces), cellularity, attachment, avascularity, regeneration

Integrity of epithelia is maintained by

1. Intercellular connections

2. Attachment to the basement membrane

3. Epithelial maintenance and repair

types of cell junctions

tight junctions, desmosomes, gap junctions

Gap junctions

allow rapid communication, held together by connexons, allow small molecules and ions to pass, found in heart muscle

Tight junctions

fusion between membranes, prevents passage of water and solutes, in digestive tract

spot desmosomes

tie cells together

hemidesmosomes

attach cells to the basement membrane

2 parts of basement membrane

basal lamina and reticular lamina

endocrine glands

release hormones into the bloodstream

exocrine glands

secrete substances through ducts onto epithelial surfaces

unicellular glands

goblet cells in epithelia of intestines secrete mucin

classification of multicellular exocrine glands

structure- simple or compound, shape of secretory portion, relationship between ducts and glandular areas

simple glands

simple tubular (intestines),

simple coiled tubular (merocrine sweat glands),

simple branched tubular (gastric glands),

simple alveolar (not found in adults),

simple branched alveolar (sebaceous glands)

compound glands

compound tubular (mouth),

compound alveolar (mammary glands),

compound tubuloalveolar (salivary glands)

three methods of secretion

merocrine, apocrine, holocrine

merocrine secretion

released by secretory vesicles, sweat glands

apocrine secretion

shedding cytoplasm, mammary glands

holocrine secretion

released by cells bursting, gland cells released by stem cells, sebaceous glands

serous glands

watery secretions

mucous glands

secrete mucins

mixed exocrine glands

both serous and mucous

functions of connective tissue

structure, support, protection, transportation, energy storage

categories of connective tissue

connective tissue proper, fluid connective tissue, supporting connective tissue

connective tissue proper

loose and dense

Cells of connective tissue proper

Fibroblasts

Fibrocytes

Adipocytes

Mesenchymal cells

Melanocytes

Macrophages

Mast cells

Lymphocytes

Microphages

Fibroblasts

most abundant, found in all types of connective tissue proper, secrete proteins and hyaluronan

fibrocytes

maintain connective tissue fibers

mesenchymal cells

stem cells that respond to injury or infection

Melanocytes

cells that produce melanin

macrophages

phagocytize foreign substances, fixed and free

mast cells

stimulate inflammation after injury or infection

release histamine and heparin

Lymphocytes

migrate throughout the body, may develop into plasma cells

Microphages

phagocytic blood cells

connective tissue fibers

collagen, elastic, reticular

collagen fibers

long, straight, and unbranched; most common fibers in connective tissue proper; strong and flexible; tendons and ligaments

reticular fibers

Fibers made of collagen fibers that are very thin and branched. Form a tightly woven fabric that joins connective tissue to adjacent tissues. sheaths around organs

elastic fibers

Flexible and "stretchy" fibers that add elasticity to tissue, elastic ligaments of vertebrae.

ground substance

fills the space between the cells and slows pathogen movement

types of loose connective tissue

areolar, adipose, reticular

areolar tissue

Binds skin to underlying organs

brown fat

many blood vessels, involved in the rapid production of heat

reticular tissue

provides support for organs

fasciae

connective tissue layers and wrappings that support and surround organs

three layers of fasciae

superficial: separates skin from underlying tissues, deep: sheets of dense regular connective tissue, subserous: between deep fascia and serous membranes that line body cavities

lymph

watery fluid monitored by immune system, returned to veins near the heart

cartilage structure

avascular, perichondrium (outer fibrous layer for support and protection and inner cellular layer for growth and maintenance)

three types of cartilage

hyaline (synovial joints and ribs), elastic (external ear), fibrocartilage (around joints and in spine)

Bone

calcified, osteocytes, periosteum

four types of tissue membranes

mucous, serous, cutaneous, synovial

mucous membranes

line passageways with external connections, in digestive tract, epithelial surfaces must be moist

serous membranes

Line cavities not open to the outside, thin but strong, parietal (inner surface of cavity) and visceral (covers organs) portions, serous fluid reduces friction

serous membranes

peritoneum (covers abdominal organs), pleura (lungs), pericardium (heart)

cutaneous membrane

skin

synovial membrane

line synovial joint cavities, synovial fluid, lack epithelium

tissue response to injury

inflammation and regeneration

inflammatory response

can be triggered by trauma or infection, damaged cells release proteins, prostaglandins, and potassium ions, damaged connective tissue activates mast cells

process of inflammation

-Lysosomes release enzymes that destroy the injured cells and attack surrounding tissues

-Tissue destruction is called necrosis (Begins several hours after injury)

-necrotic tissues and cellular debris (pus) accumulate

Regeneration

epithelia, connective tissues, and smooth muscles regenerate well

skeletal, cardiac, nervous tissues regenerate poorly or don't

damaged cardiac muscle cells are replaced by fibrous tissue

Cardinal signs of inflammation

redness, swelling, heat, pain, loss of function

Epidermis

stratified squamous epithelium, avascular, nutrients are diffused from capillaries in the dermis

keratinocytes

The most abundant epidermal cells, produce keratin.

layers of epidermis

stratum corneum, (stratum lucidum), stratum granulosum, stratum spinosum, stratum basale

tactile discs

cells with sensory nerve endings, found in hairless skin, respond to touch

2 ways water is lost from skin

insensible perspiration (diffusion) and sensible perspiration (sweat glands)

Epidermal growth factor

produced by salivary glands and duodenum, promotes division of basal cells, accelerates keratin production, stimulates epidermal repair and glandular secretion

papillary layer

areolar tissue, contains capillaries, lymphatic vessels, and sensory neurons

dermatitis

inflammation of the papillary layer

reticular layer

dense irregular connective tissue, contains collagen and elastic fibers, contains all cells of connective tissue proper

skin turgor

flexibility and resilience of skin

loss of skin turgor is caused by

dehydration, aging, hormones, UV radiation

tension lines

parallel bundles of collagen and elastic fibers oriented to resist the forces applied to the skin during normal movement, cuts made parallel heal well, cuts made at right angles leave scars

dermal blood supply

cutaneous plexus (arteries in reticular layer), subpapillary plexus (arteries in papillary layer)

innervation of skin

Nerve fibers in skin and sensory receptors (tactile and lamellar corpuscles)

Vitamin D3

produced by epidermal cells with UV radiation, converted into calcitriol, essential for absorption of calcium and phosphate ions, insufficient D3 can cause rickets

exocrine glands in skin

sebaceous glands (holocrine) and sweat glands (apocrine and eccrine)

types of sebaceous glands

1. Simple branched alveolar glands (hair follicles)

2. Sebaceous follicles (skin)

Repair of the Integument

inflammatory phase, migratory phase, proliferation phase, scarring phase

Bone shapes

sutural, long, short, flat, irregular, sesamoid

sutural bones

small, flat, between the flat bones of the skull

irregular bones

complex shapes, vertebrae

short bones

boxy, carpal bones and tarsal bones

flat bones

thin, skull

long bones

arms and legs

sesamoid bones

small, round, flat, in knee cap, hands and feet

projections

where muscles, tendons, and ligaments attach

openings and depressions

for passage of blood vessels and nerves

ramus

part of a bone that forms an angle with the rest of the structure

sinus

A chamber within a bone, normally filled with air

foramen

A rounded passageway for blood vessels or nerves

fissure

deep furrow, cleft, or slit

Meatus

canal-like passageway

canal

duct or channel

sulcus

narrow groove

fossa

shallow depression

Torchanter

large, rough projection

spine

pointed process

tubercle

small, rounded projection

tuberosity

rough projection