Chaps 5, 6, and 8 exam

skin, hair, nails, glands

structures a part of integument

Protection against UV light, water loss, and microorganisms

Sensation receptors for temperature, touch, pressure, pain

Temperature regulation

Vitamin D production

Excretion of small amounts of waste

Funtions of integumentary system

Epidermis

Superficial layer of epithelial tissue

Dermis

Deep layer of connective tissue

Subcutaneous tissue

NOT part of skin

Loose connective tissue that connects skin to underlying structures

Epidermis

Dermis

parts of skin?

Epidermal Strata

Stratum basale

Stratum spinosum

Stratum granulosm

Stratum lucidum

Stratum corneum

Stratum basale

deepest portion of epidemis and single layer.

High miotic activity and cells become keratinized

stratum spinosum

Limited cell division, contain desmosomes, lamellar bodies, and additional keratin fibers

stratum granulosum

contains keratohyalin

in superficial layers, nucleus and other organelles degenerate and cell dies

stratum lucidum

thin, clear zone

found only in palms and soles

stratum corneum

most superficial and consists of cornified cells

thick skin

has 5 epithelial strata

found in areas subject to pressure or friction (palms of hands, fingertips, soles of feet)

fingerprints and footprints

thin skin

composed of 4 strata (no stratum lucidum)

more flexible than thick skin

covers rest of body

hair grows here

callus

increase in number of layers in stratum corneum

when this occurs over a bony prominence a corn forms.

cyanosis

blue color caused by decrease in blood oxygen content

erythema

red color caused by increased blood flow

dermis contains

contains nerves, blood vessels, hair follicles, smooth muscles, glands, and lymphatic vessels.

dermis function

sensory functions:

pain, itch, tickle, temperature, touch, pressure, two-point discrimination

subcutaneous tissue/hypodermis

deep to skin

contains: fibroblasts, adipose cells (1/2 of body’s adipose tissue), machrophages

subcutaneous tissue function

energy source

insulation

padding

arrector pili

type of smooth muscle

skin pushed up by movement of hair follicle

muscle contraction causes “hair to stand up”

sebaceous glands

holocrine (death of secretory cells)

oily secretion

prevents drying

apocrine

eccrine (merocrine)

two types of sweat glands

eccrine (merocrine) glands

most common

produce isotonic fluid (sweat) containing mostly water and some wastes.

numerous in palms and soles

appocrine glands

active at puberty

found in axillae, genitalia (external labia, scrotum), around anus.

ceruminous glands

modified merocrine sweat glands, external auditory meatus

cerumen (earwax)

in combonation with hairs, prevents dirt and insexts from entry and keeps eardrum supple

mammary glands

modified apocrine sweat glads that produce milk

stratum corneum

nail body

burns are measured in?

partial thickness: first degree (epidermis), second degree (epidermis and dermis)

full thickness: third degree (epidermis, dermis and subcutaneous tissue)

fourth degree affects deeper structures

skeletal system functions

support

protection

movement

storage

blood cell production

osteomalacia

if mineral removed bone bendy

osteoporosis

if collagen removed bone very brittle

mesenchyme stem cells

osteochondral progenitor (original) cells become chondroblasts or osteoblasts

trabeculae

interconnecting rods of plates of bone (scaffolding)

trabeculae contain

spaces filled with marrow

covered with endosteum

oriented along stress lines

central or haversian canals

parallel to long axis

contain blood vessels

lamellae

concentric, circumferential, interstitial.

osteon or haversian system

central canal, contents, associated concentric lamellae and osteocytes.

perforating or volkmanns canal

perpendicular to long axis.

contain blood vessels

direct flow of nutrients from vessels through cell processes of osteoblasts and from one cell to the next.

perforating canals

deliver blood to central canals

run perpendicular to length of the bone

diaphysis

shaft primarily made of compact bone

epiphysis

end of bone primatily made of spongy bone

epiphyseal plate: growth

hyaline cartilage; present until growth stops

epiphyseal line

bone stops growing in length

medullary cavity (child)

in children medullary cavity is red marrow

medullary cavity (adult)

in adults, red marrow is replaced by yellow in limb bones (except for proximal epiphyses of arm and thigh bones). Elsewhere, varying proportions of yellow/red marrows are found

periosteum

outer fibrous

inner is single layer of bone cells including osteoblasts, osteoclasts, and osteochondral progenitor cells

fibers of tendon become continuous with fibers of periosteum

Sharpey’s fibers

some periosteal fibers penetrate through the periosteum and into the bone. this strengthens the attachment of tendon to bone.

endosteum

similiar to periosteum, but more cellular. Lines all internal spaces including spaces in spongy bone.

Flat bones

no diaphyses, epiphyses

sandwhich of spongy

short and irregular bones

no diaphyses and not elongated

some flat and irregular bones of skull have sinuses lined by mucous membranes

sinuses lined by mucous membranes

Intramembranous ossification

takes place in connective tissue membrane

endochondral ossification

takes place in cartilage

Intramembranous ossification

bone development

which type of ossification forms skull bones, parts of mandible, diaphyses of clavicles?

what are fontanels?

Large membrance-covered spaces between developing skull bones; unossified.

what occurs at the epiphyseal plate?

bone grows in length organized into 5 zones

interstitial cartilage growth

when bone grows in length in anatomy terms is?

When bone grows in diameter

Appositional growth on the surface of the cartilage.

what happens to the epiphyseal plate when bone growth finishes?

It ossifies and becomes the epiphyseal line, stopping further height growth.

At what age range does the closure of the epiphyseal plate typically occur?

Between 12 and 25 years of age.

What can affect bone growth?

vitamin D levels

rickets:lack of vitamin D during childhood

Vitamin C levels

osteomalacia is the lack of what during adulthood?

lack of vitamin D leading to softening of bones.

Scurvy

Defiency of vitamin C

How does a lack of vitamin c affect the body?

wounds heal slower and teeth can fall out

Where does Growth Hormone come from, and what is its main job?

Origin The anterior pituitary gland (at the base of the brain).

Job: It acts as the body's "Build More!" signal to make you grow bigger and taller.

What is interstitial cartilage growth?

growth in length

What is appositional bone growth?

growth on the surface of cartilage (growth in diameter)

what hormone is required for growth of all tissues?

Thyroid hormone is requires for growth of all tissues.

What do reproductive hormones cause?

Estrogen and testosterone cause growth at puberty and closure of epiphyseal plates and the cessation of growth.

Increased stress causes what to the bones?

increase in strength

what is fracture classification based on?

mechanism of fracture

soft-tissue damage

displacement versus nondisplacement

fracture pattern

number of fragments in the fractured bone

age specific

what are the possible mechanisms of fractures?

traumatic

disease

pathologic

when trying to classify soft tissue damage you have to analyze?

closed versus open

types of fracture patterns

linear

spiral

avulsion

stress

compression

The number of fragments in the fractured bone is?

incomplete

complete

communited

when looking at age specific fracture classification what must we identify?

greenstick and epiphyseal features

The level of calcium in the blood depends upon movement of?

calcium enters bone when osteoblasts create new bone and calcium leaves bone when osteoclasts break down bone

what controls blood calcium levels

parathyroid hormone (PTH)

calcitriol

calcitonin

what are the direct affects of the parathyroid hormone (PTH)?

Activates osteoclasts, increases number of osteoclasts, and prevents inhibition of osteoclst formation.

more osteoclast activity impacts the bone how?

Bone is reabsorbed and calcium released into blood.

calcitriol does what and is from where?

Increases blood calcium by stimulating intestinal absorption of calcium.

Derived from vitamin D3.

calcitonin does what?

lowers blood calcium by inhibiting osteoclast activity

what decreases as the skeletal system ages?

Bone matrix decreases and bone mass, posture and potenially teeth

when does bone mass decrease and which sex has denser bone?

after 30 years old and men due to testosterone and greater weight

what is the structural classification of joints based on?

the major connective tissue type that binds the bones together

what are the three major structural categories of joints?

Fibrous

Cartilaginous

Synovial

which structural joint type is bound by dense fibrous connective tissue?

Fibrous joint

Which structural joint type is united tightly by cartilage?

Cartilaginous joint

which structural joint features a joint cavity surrounded by a membrane?

synovial joint

what is the functional classification of joints based on?

the degree of motion allowed

what are three functional categories of joints?

synarthrosis

amphiarthrosis

diarthrosis

what is synarthrosis?

a non-movable joint

what is an amphiarthrosis?

a slightly moveable joint

what is a diarthrosis?

a freely moveable joint

Characteristics of fibrous joints?

united by fibrous connective tissue (strong threads that lock bones together tightly)

have no joint cavity (two bones are directly cemented together by solid collagen fibers; designed for protection rather than movement (shock absorber))

move little or none (cement or heavy duty rivets holding bone in place against one another)

Bones farther apart than suture and joined by ligaments

some movement may occur

(Ex. radioulnar (intreosseus membrane)

syndesmoses