Anatomy and Physiology-WGU

carpal

wrist

crural

legs

coxal

hip

inguinal

groin

sacral

base of spine

caudal

towards the tail

laterally

towards the side

sagittal

vertical division to left and right

transverse

horizontal division to up and down

coronal

vertical division to front and back

four vital functions of life:

1) exchange with environment

2) transport of fluids and material through the body

3) provision of structure, protection and movement

4) regulation and control of processes

integumentary system functions

1) outer protective layer

2) prevention of fluid loss

3) obtainment of information form outside

4) thermoregulation

5) making Vitamin D

3 layers of skin

1) epidermis

2) dermis

3) hypodermis

layers of epidermis

1) stratum basale

2) stratum spinosum

3) stratum granulosum

4) stratum ludicum

5) stratum corneum

stratum basale

1) deepest

2) single layer of basal cells

3) replaces cells

4) melanocytes, Langerhans cells, Merkel cells

stratum spinosum

1) spiny appearance

2) Desmosomes as cell junctions visible under microscope

3) 8-10 layers

stratum granulosum

1) grainy apprarance

2) 3-5 layers

3) flatter shape

4) lots of keratin excreted

stratum ludicum

1) lucid, clear

2) palms od hands, sole of feet

stratum corneum

1) most superficial layer

2) 15-30 dead cell layers

3) dry, prevention of growth of microbes

4) sheds every 2 weeks

Merkel cells

can detect light touch

Dendritic or Langerhans cells

tissue macrophages, immune, engulf and signal

dermis

contains most structures

structures in dermis

1) blood vessels

2) sweat glands

3) oil glands

4) sensory receptors

4) lymph vessels

sweat

mostly water, also waste products (urea), electrolytes

sebaceous glands

1)produce oil (sebum),

2) against microbes

3) softness of skin

4) hydrophobicity of skin

layers of dermis

1) loose papillary layer

2) dense irregular layer

hypodermis

1) loose connective tissue

2) fat

hair

1) regulation of body heat

2) protection of body

nails

1) protection of fingers and toes

2) mechanical support

eccrine (merocrine) glands

1) on skin surface

2) derived from epidermis

3) with pore opening on skin surface

4) mostly water, salt, antimicrobial, waste.

5) Thermoregulation

6) by sympathetic nervous system

apocrine glands

1) moisten skin with emotional upset

2) armpits and genitals

3) more fatty acids

4) body odor

5) inactive until puberty

ceruminous glands

earwax

mammary glands

milk

non-barrier functions of skin

1) synthesis of cholecalciferol (precursor to Vitamin D)

2) temperature regulation

3) non-verbal communication (muscles can insert into dermis)

functions of hypodermis

1) connection to lower structures

2) insulation

3) energy storage (fat)

functions of skeletal system

1) structure

2) protection

3) support of body structures

4) movement

5) maintenance of homeostasis

6) hematopoiesis

tendons

here classified as belonging to skeletal system, can also be muscular system

basic facts of bones

1) 206 in human

2) smallest: ossicles in ear

3) largest: femur

4) formation of blood cells in bone marrow

5) can be considered an organ with osseous tissue, cartilage, fibrous connective tissue, blood vessels, nervous tissue

cancellous (trabecular, spongy) bone

1) spongy appearance

2) less weight and brittleness

3) at ends of bones where forces are high

4) allow for bends without cracking

5) lamellae form random mesh-like structures

6) example: flat bones of skull

compact (dense, cortical) bone

1) stronger

2) always on outside of bone

3) packed miscrostructure arranged in rings

4) Osteons

5) osteons in direction of load-bearing axis

6) have canal for blood vessels

lacunae

1) small cavities within osteons

2) connected by canaliculus

3) oriented around central canal

4) parallel to lamellae

osteocytes

) long processes,

2) connect to other osteocytes and act as sensor

3) regulate osteoblasts and clasts

diaphyses

bone shaft

periosteum

membrane layer covering outside of bone

osteoblasts

1) make bone

2) after mineralization: trapped in bone, differentiate to osteocytes

osteoclasts

break bone down

epiphysis

at end of bone, mostly spongy and red bone marrow

metaphysis

between dia and epiphysis

epiphyseal plate:

1) in children

2) between meta and epiphysis

3) layer of hyaline cartilage allowing for bone to grow

4) becomes calcified in adults

short bones

similar length in all directions

wrist, ankle

flat bones

flat,plate like: Skull

irregular

no defined shape: vertebrae, hip

ossification - skull and clavicle

intermembrane ossification: directly from stem cells

ossification all regular bones

endochondral ossification: cartilage template forms first and is replaced by mineralized bone tissue over time

step 1 of endochondral ossification

formation of hyaline cartilage template in the right shape, covered by perichondrium

step 2 of endochondral ossification

growth of template: perichondrium produces chondrocytes, producing cartilage

step 3 of endochondral ossification

initiation of bone formation: perichindrium switches from chondrocytes to osteoblasts, thin layer of bone around cartilage

step4 of endochondral ossification

formation of marrow cavities and ossification of diaphysis

step 5 of endochondral ossification

ossification of epiphysis

growth stages

1) longitudinal: until 18 in women, 21 in men

2) appositional for whole life

hyoid bone

1) not connected to any other

2) supports tonge movement

vertebrae general

1) 33

2) 7 cervical

3) 12 thoracic

4) 5 lumbar

5) 9 fused sacral

true ribs

1) 7

2) direct connection to sternum

false ribs

1) 7

2) no direct connection to sternum

floating ribs

1) 2

2) do not connect at all

pectoral girdle

1) scapula

2) clavicle

arm bones

1) humerus

2) radius

3) ulna

4) wrist

pelvic girdle bones

1) femur

2) tibia (shin)

3) fibula (calf)

4) foot

5) patella (kneecap)

red blood cells

1) red

2) disc-shaped

3) no visible organelles

4) O2 transfer

5) circulate ~120 days

6) ~2 mio per second made

platelets

1) minicells, much smaller than others

2) have organelle

3) blood clotting

white blood cells

1) internal structure, with nucleus

2) immune cells

2 ways of classifying joints

1) material

2) movement

joint classifications by material

1) fibrous tissue between the bones - examples: bones of cranium (sutures between), teeth with periodontal ligament

2) cartilageous - examples: vertebrae, ribs -> sternum

3) synovial - cavity with synavial fluid - knee - synovial fluid resembles the white of an egg

joint classification by movement

1) immovable: sutures - synarthrotic

2) slightly movable: vertebrae -amphiarthrotic

3) freely movable: articulation joints diarthrotic

types of articulation joints

1) ball-and-socket: 2 axis AND rotation: shoulder and hip

2) hinge: only 1 axis, protrusion of one end fits in intrusion of the other - elbow, knee

3) saddle: base of the tumb

4) gliding (plane): between flat surfaces - wrist

5) condyloid: in 2 axis, NO rotation - fingers and toes

Ca too low makes:

nervous system overexcited -> muscles rigid

Ca too high makes:

heart and digestion rate slow down

PTH effect

increased osteoclast resorption, more Ca available, more uptake, less loss over urine

calcitonin effect

in children, decreases bone resorption, less Ca in blood

calcitriol (vitamin D)

more absorption

muscular system general

1) only voluntary muscles counted

2) more than 650

myocytes

all muscle cells of muscles

muscle actin proteins

1) actin

2) myosin

myofibrils

connection of actin and myosin

sarcomeres

1) repeated myofibrils

2) several in muscle cell

stimulation of muscle cells

1) via acetylcholine

2) causes pulse of Ca

3) -> contraction

skeletal muscle

1) fusion of muscle cells

2) multinucleated

3) striated: organized sarcomeres

smooth muscle

1) one nucleus

2) no sarcomeres

cardiac muscle

1) one nucleus, in center of cell

2) striated

3) shorter than skeletal

4) branched: connected via "intercalated discs"

5) have gap junctions for quick transmission of action potentials

6) desmosomes for structural integrity

7) contractile cell

8) pacemaker cell

3 layers of connective tissue of skeletal muscle

1) epimysium

2) perimysium

3) endomysium

epimysium

1) thick collagen

2) separates from organs

3) contraction and movement

perimysium

collagen, but also elastic fibers

endomysium

1) inside each fascicle

2) encases each myocyte

3) thin layer with blood vessels and neurons

fascicles

groups of myocytes inside epimysium

sarcolemma

1)myocyte plasma membrane

2) generally more proteins than normal cells

neuromuscular junction

specific stimulation site of sarcolemma

transverse tubules

indentation in muscle cells to get action potential deep into the muscle cell. Filled with extracellular liquid

sarcoplastic reticulum

1) similar to endoplasmis

2) tubes of it surround each myofibril

3) filled with high CA+ fluid

teminal cisternae

holes in sarcoplastic reticulum

sarcomere

1) up to 100.000 repeating sarcomeres in myocyte