1.1 & 1.2 Flashcards
Integumentary system structure and function
Function:
- protect
- contain structures
- thermal regulation
- sensation
- synthesize & store vitamin D
- eliminate waste
Structures:
- skin & fascia
- hair
- finger & toe nails
- glands
- hair follicles
- arrector muscles
Layers of skin
Epidermis:
- waterproof and avascular
- multiple layers… deepest one regenerates
- contains keratinocytes, immune cells, & melanocytes
- role in protection, sensation, & vitamin D production
Dermis:
- tone, tough, vascular
- has collagen, elastic fibers, & terminal nerves (receive sensation input)
- role in protection, sensation, & thermal regulation
Subcutaneous:
- insulation & padding
- loose connective tissue & fat
- neurovascular
- thickness varies by individual and body part
- role in protection & thermal regulation
Fascia
Functions in containment
2 types: superficial and deep with skin ligaments extending between them
Structures:
- facial compartments
- retinaculum
- bursae
- synovial tendon sheath
- serous membrane
- subserous fascia
Skeletal system function and structure
Function:
- support (bone is chief supporting tissue)
- protect
- movement
- storage of salt
- new blood cell production (in medullary cavity by bone marrow)
Structure:
- Cartilage
* resilient with semi-rigid connective tissue
* flexible, cushions and reduces friction at articular surfaces
- Bone
* firm with rigid connective tissue
Bone types, shapes, divisions
Types:
- compact
- spongy (harder to break)
Shapes:
- long (humerus)
- short (carpals)
- flat (parietal)
- irregular (vertebrae)
- sesamoid (patella)
Skeletal divisions:
- axial (skull, spine, rib cage, sacrum, hyoid)
- appendicular (upper and lower extremities)
Bone development
- intramembranous calcification
- endochondral calcification
1. Mesenchyme forms cartilage
2. Calcification (rigidity) and capillary formation- capillaries become the periosteal bud
- Capillaries initiate primary ossification center which has a rich blood supply.
- Periosteal bud becomes the nutrient artery and secondary ossification center forms.
- Bone lengthens along the diaphysis until epiphyseal plates are replaced by bone.
- capillaries become the periosteal bud
Joint classes
Fibrous:
- sutures
- gomphosis
- syndesmosis
Cartilaginous:
- primary (in a bone)
- secondary (between bones)
Synovial: united by fibrous capsule, lines with synovial membrane, space filled with synovial fluid
- pivot
- plane
- hinge
- saddle
- ball and socket
- condyloid
Muscular system function
movement
give form
generate heat
stabilize joints
maintain posture
support circulation
protect organs
Muscular contraction and movement
Contraction:
- isotonic - muscle length changes, tension doesn’t
- isometric - muscle length stays the same, tension changes
Movement:
- prime mover - responsible for movement
- fixator - stabilizes proximal aspect
- synergist - works with prime mover
- antagonist - opposed the action
Muscle tissue types
cardiac (involuntary)
skeletal (voluntary)
smooth (involuntary)
Muscle tissue structure
contractile portion
tendons attach muscles to bones, cartilage, or other muscles
length = distance between attachments
origin - point of stable attachment
insertion - point that moves
name is based on function or bone it’s attached to
Muscle fiber
endomysium (one fiber)
perimysium (group of fibers)
epimysium (entire mucle)
motor unit
consists of one motor neuron and all the fibers it controls
- when one motor unit is stimulated all its fibers contract
cardiac muscle function
forms heart wall
involuntary
intrinsic regulation
rich blood supply
smooth muscle location and features
location:
- vasculature
- organs and ducts
- skin
- eyes
features:
- multiple sources of activation
- slow, long, great action
circulatory system function
transport nutrients, gases, and wastes
thermoregulation
maintain fluid balance
protect against blood loss and infection
circulatory system circuits
pulmonary and systemic
blood vessels
arteries: carry blood under high pressure away from the heart; get smaller as they branch away from the heart; thick, elastic muscular walls
veins: carry blood under low pressure toward the heart, often against gravity; more abundant; size increases toward the heart; thin walls with valves in the lumen
blood vessel walls
- tunica intima - flat epithelial cells (endothelium)
- tunica media - smooth muscle
- tunica adventitia - connective tissue
vein/artery pairing
travel together, 1 artery with 2+ veins
countercurrent heat exchanger: heat moves from the warmer arterial system to cooler venous system
musculovenous pump: muscles surrounding the veins push veins when they contract, forcing blood toward the heart
capillary function and structure
function:
- allow the exchange of nutrients and waste between intravascular and extravascular spaces
structure:
- simple endothelial layered tubed covered with a basement membrane
capillary filtration
As blood flows from high arterial pressure to low venous pressure, blood filters through capillary walls into surrounding tissue driven by high hydrostatic pressure.
On the venous side, fluid flows back into capillary circulation driven by oncotic pressure.
hydrostatic: pressure of fluid, main driver
oncotic: # of ions on one side of membrane compared to the other
Lymph system function and structures
function:
- eliminate unwanted materials
- absorb and transport fat
- form defense mechanisms
structures:
- capillaries: single celled endothelial tubes without basemsent membranes
- vessels: thin walls with one way valves
- trunks: large collecting vessels which drain lymph vessels, often into the cisterna chyli
- nodes: small masses distributed along lymph vessels which filter lymph fluid
-ducts
lymph fluid contains
capillary filtrate
bacteria
cell debris
rare plasma proteins
other cells, such as lymphocytes
