Movement: Muscles, Bones & Joints 2020

ligament

connective tissue attaching bone to bone

tendon

connective tissue that attaches muscle to bone

fascicle

consists of bundles of muscle fibers

muscle fiber

consists of bundles of myofibrils; also called a muscle cell

myofibril

consists of bundles of myofilaments

involuntary muscle movement

controlled by the unconscious part of the brain such as heartbeat, intestine moving waste, breathing

osteoporosis

disorder in which bones lose their density and can break easily

bursa

enclosed sac filled with viscous synovial fluid located in joint areas of potential friction

collagen

fibrous structural protein found in the skin and connective tissue

compact bone

hard, strong type of bone is dense and looks smooth

calcium and phosphorus

important elements for building strong bones

spongy bone

lightweight inner bone containing marrow, looks like it has tiny holes throughout

red bone marrow

marrow found in the spaces of spongy bone where red and white blood cells are made

osteocytes

mature bone cells

flexion

movement at the joint which decreases the anglebetween the two bones

extension

movement at the joint which increases the angle between two bones

neuromuscular junction

point of contact between a motor neuron and a skeletal muscle cell

axial skeleton

portion of the skeletal system that consists of the skull, rib cage, and vertebral column

ossification

process of bone formation

bone matrix

rigid framework of bone that consists of tough protein fibers and mineral crystals

sarcomere

single contractile unit of muscle tissue, the distance from one Z line to another Z line

myofilaments

smallest unit of skeletal muscle tissue examples include myosin and actin, bundles make up myofibrils

cartilage

strong, flexible tissue that provides cushioning at your joints & makes up some body parts such as your nose and ears

growth plate

the area just below the head of a long bone in which growth in bone length occurs, a.k.a. the epiphyseal plate.

myosin

thick myofilament,consists of golf club-like heads that bind to actin

actin

thin myofilament, contains two "blocking" compounds (troponin and tropomyosin)

contraction

tightening & shortening muscles

saddle joint

type of moveable joint in which one bone forming the joint is shaped like a saddle with the other bone resting on it. E.g., bottom thumb joint

condyloid / ellipsoid joint

type of moveable joint made of oval-shaped bone that fits into an elliptical cavity E.g., wrist bones

ball and socket joint

type of synovial joint in which the rounded surface of one round bone fits into the cup-like depression of another bone E.g., shoulder and hip

pivot joint

type of synovial joint that allows only a rotating motion E.g., upper neck, radius in elbow

gliding / planar / plane joint

type of synovial joint which allows the bones to slide past one another on a flat surface E.g., ankles, spine in low back

hinge joint

type of synovial joint which is formed between two or more bones where the bones can only move along the axis to flex or extend E.g., knee and ulna in elbow

oppositional muscle pair

when one muscle of a pair contracts, the other relaxes and vice versa to create movement in both directions E.g., bicep and tricep

joint

where 2 or more bones meet, allow us to bend, twist, or turn our bodies

voluntary muscle movement

you control this type of movement

cardiac muscle

Shape: branched, striated cells with intercalated discs to separate one cell from another Nucleus: one Control: involuntary Found: in the walls of heart muscle

skeletal muscle

Shape: elongated, striated cylindrical cells Nucleus: multinucleated Control: voluntary Found: attached to bones

smooth Muscle

Shape: spindle Nucleus: one Control: involuntary Found: in the walls of soft organs or blood vessels

yellow bone marrow

a soft yellow substance inside bones that stores fat

rickets

a softening and weakening of bones in children, usually due to inadequate vitamin D

bones

alive, layered, growing and changing all the time, they provide structure, make blood cells, store fats and minerals for the body

freely movable joint

allows large range of movement

partially movable joint

allows only small movement of bones

immovable joint

also called fixed joints, these bones are interlocked or fused and held by connective tissues E.g., skull bones

Z line

attachment site that serves to anchor actin filaments in place in a sarcomere

M line

attachment site that serves to anchor myosin filaments in place in a sacromere

osteoclast

bone cell that absorbs and removes unwanted bony tissue

osteoblasts

bone-building cells that secrete matrix

apendicular skeleton

bones of the limbs and girdles (legs, arms, pectoral/pelvic girdles)