Musculoskeletal System

function of the musculoskeletal system

support, allow movement, proetct

musculoskeletal system helps one maintain ___ posture

upright

musculoskeletal system encloses

vital organs

what type of skeleton do soft bodied animals such as sea anemones, earthworms, cnidaria, and other invertebrates have

hydrostatic skeleton

what is the hydrostatic skeleton formed by

fluid filled compartment within the body (coelom)

hydrostatic skeleton- compartment is under ____ pressure because of the fluid, and supports the other organs of the organism

hydrostatic

function of the exoskeleton

external hard encasement, defense from predators, supports the body, allows for movement (contraction of attached muscle)

exoskeletons are made of

chitin

do exoskeletons grow

no

are endoskeletons inside or outside

inside

endoskeleton is ___ and more ___ than exoskeleton

stronger and more supportive

endoskeletons are _____ structures located within the soft tissue of organisms

hard, mineralized

endoskeletons provide ____ for the body

support

endoskeletons ___ internal organs

protect

endoskeletons allow for ___ through contraction of muscles attached to the skeleton

movement

what are the bones down the midline

axial skeleton

what bones are apart of the axial skeleton

bones of the skull, ossicles of the middle ear, hyoid bone, vertebral column, rib cage

function of the skull

supports structure of the face, protects the brain

what do cranial bones include

frontal, parietal, and sphenoid bones

what area do cranial bones cover

the top of the head

role of facial bones

form the face, provide cavities for the eyes, nose, mouth

how many cervical vertebrae are there

7

how many thoracic vertebrae are there

12

how many lumbar vertebrae are there

5

the sacrum at one point during development

was multiple bones but they fused together

spinal curves increase ___ and ___

strength and flexibility of the spine

function of the thoracic cage

protects the heart and lungs

the appendicular skeleton is composed of (not specific)

everything that is not a part of the axial skeleton

the appendicular skeleton is composed of (specific )

pectoral limbs, pelvic limbs, pectoral girdle, pelvic gridle

the upper limbs are axial or appendicular

appendicular

the upper limbs consist of

humerus, radius and ulna, 8 carpal bones, 5 metacarpal bones, 14 phalange bones

female pelvis differences than males

lighter, wider, shallower, and has a broader angle between the pubic bones

the lower limbs consist of

femur, patella, tibia and fibula, tarsals, metatarsals, phalanges

what are the types of bones

long bone, short bone, flat bone, irregular bone

what type of tissue is bone

osseous tissue which is connective tissue

matrix bones consist of

mineral salts and collagen fibers

what is calcification

the process of deposition of mineral salts on the collagen fiber matrix that crystalizes and hardens the tissue

what are the four types of cells that bones consist of

osteoblasts, osteoclasts, osteocytes, osteoprogenitor

function of osteoblasts

bone formation

function of osteoclasts

remove bone structure

what are osteocytes

mature bones cells that are the main cells in bony connective tissue, these cells cannot divide

what are osteoprogenitor cells

squamous stem cells

function of osteoprogenitor cells

divide to produce daughter cells that differentiate into osteoblasts

what are the 3 categories of joints based on functionality

fibrous joints, cartilaginous joints, synovial joints

fibrous joints =

immovable joints

cartilaginous joints =

allow slight movement

synovial joints =

allow free movement of the joint

what are fibrous joints held together by

fibrous connective tissue

what are cartilaginous joints connected by

cartilage

only joints have a space or cavity in joint

synovial joint

what is the cavity in synovial joints filled with

synovial fluid which lubricates the joints

what are the different types of synovial joints

planar, hinge, pivot, condyloid, saddle, ball-and-socket

joints of the carpal bones in the wrist

planar joints

elbow joint where the radius articulates with the humerus

hinge joint

joint in the neck that allows the head to move back and forth

pivot joint

metacarpophalangeal joints in the finger

condyloid joint

carpometacarpal joint - base of the thumb

saddle joint

shoulder and hip

ball and socket joint

what are the three types of muscles tissue

skeletal muscle, smooth muscle, cardiac muscle

what is a muscle fiber

a single cylindrical muscle cell

what are muscle fibers composed of

myofibrils packaged into orderly units

myofibrils are made up of units called

sarcomeres

what is the region of one Z line to the next Z line

a sarcomere

actin=

thin filament (z line)

myosin

thick filament (m line)

when a sarcomere contracts what happens

the z lines move closer together and the I bands get smaller

the A bands stay the same width and at full contraction the thin filaments ___

overlap

isometric contraction muscle does not

shorten

isotonic contraction causes

movement

isotonic contraction - concentric

muscle fibers shorten

isotonic contraction - eccentric

muscle fibers lengthen