BIOMED unit 1 test

Muscle rule 1

Muscles must have at least two attachments and must cross at least one joint

Muscle rule 2

Muscles always pull and get shorter

Muscle rule 3

The attachment that moves is known as the insertion and the attachment that remains stationary is known as the origin

Muscle rule 4

Muscles that decrease the angle between ventral surfaces of the body are known as flexors. Muscles that increase the angle between ventral surfaces of the body are known as extensors

Muscle rule 5

Muscles work in opposing pairs

Muscle rule 6

Muscle striations point to the attachments and show the direction of pull

Intercostal location

between the ribs

Intercostal action

Inhalation and exhalation

serratus anterior origin

Lateral surface of ribs

serratus anterior insertion

medial border of scapula

serratus anterior action

Extending arm

pectoralis minor origin

ribs 3-5

Pectoralis minor insertion

coracoid process of scapula

Pectoralis minor action

Assist in extending arms forward

Pectoralis major abdominal head origin

ribs 5-7

Pectoralis major abdominal head insertion

lateral edge of humerus

Pectoralis major action

flexes, adducts, and medially rotates arm

Pectoralis major sternal head origin

ribs 1-5

Pectoralis major sternal head insertion

later edge of humerus

Pectoralis major clavicular head origin

medial half of inferior edge of clavicle

Pectoralis major clavicular head insertion

Later edge of humerus

Sacrolemma

specialized cell membrane to hold calcium ions

Z disc

anchors actin

M line

Center of sarcomere and anchors myosin

thick filaments

myosin

thin filaments

actin

Sarcomere

Contractile unit of muscle

Myofibril

Composed of repeating sections of sarcomeres

Myofilaments

actin and myosin

Troponin

attachment site on actin for Ca2+

Tropomyosin

covers myosin binding sites on actin

Contraction step 1

nerve impulse arrives at axon terminal of motor neuron and triggers release of acetylcholine (Ach)

Contraction step 2

Ach diffuses across cleft, binds to its receptors in the motor end plate, and triggers muscle action potential

Contraction step 3

Acetylcholinesterase in synaptic cleft destroys ACh so another muscle action potential does not arise unless more ACh is released from motor neuron

Contraction step 4

Muscle AP traveling along t-tubule opens ca2+ release channels in the sarcoplasmic reticulum (SR) which allows calcium ions to flood into the sarcoplasm

Contraction step 5

Ca2+ binds to troponin on actin, exposing the binding site for myosin

Contraction step 6

Contraction: power stroke use ATP; myosin heads bind to actin, swivel, and release; thin filaments are pulled to the center of sarcomere

Contraction step 7

Ca2+ release channels in SR close and ca2+ active transport pumps use to restore low level of calcium ions in sarcoplasm

Contraction step 8

Troponin-tropomyosin complex slides back into position where it blocks the myosin-binding sites on actin

skeletal muscle

striated and voluntary, attached to bone and is all around body, contracts to produce movement

cardiac muscle

striated but not voluntary, only located in heart, pumps the heart

smooth muscle

non-striated, involuntary, located in walls of blood vessels, stomach, intestines, maintains blood pressure and flow

Epimysium

surrounds entire muscle

Perimysium

Connective tissue surrounding a fascicle

Fascicle

bundle of muscle fibers

Endomysium

Connective tissue surrounding a muscle fiber

muscle sprain

a stretch or tear to the ligament

muscle strain

a stretch, tear, or rip in the muscle or its tendon

What connects muscles to bone?

tendons

What do ligaments do?

Connect bone to bone

What is the common name for scapula?

shoulder blade

What is the common name for patella?

Knee cap

What is the common name for tibia?

shin bone

What is the common name for tarsals?

ankle

What is the common name for phalanges?

fingers, toes

What is the common name for carpals?

wrist

What is the common name for clavicle?

collar bone

What is compact bone?

dense outer layer of long bone, provides strength and protection

What is spongy bone?

Inner layer of flat and irregular bones, porous structure, provides shock absorption and weight reduction

What is a long bone?

Has an iregular epiphysis at each end, composed mainly of spongy (cancellous) bone, and a shaft or diaphysis, composed mainly of compact bone. ex. Tibia fibula

What is short bone?

A short bone enables finer controlled movements, mostly spongy bone, shaped as a cube. ex. wrist bones

What is a flat bone?

Layer of spongy bone between two layers of compact bone, marrow without marrow cavity. ex. occipital bone

What is irregular bone?

complex shapes and often protect organs. Ex. Vertebrae

Where can you find yellow bone marrow?

in the medullary cavity of long bones

What is yellow bone marrow

Yellow Bone Marrow is Red Bone Marrow that has changed to fat.

What is the medullary cavity?

marrow cavity

What is red bone marrow?

Active marrow that continues to produce blood cells.

What is the periosteum?

the tough membrane that covers the outside of the bone

What is the diaphysis?

shaft of a long bone

What is the epiphysis?

ends of long bone

What is the epiphyseal plate?

flat plate of hyaline cartilage seen in young, growing bone

What is articular cartilage?

Covers the external surface of the epiphyses. Made of hyaline cartilage
Decreases friction at joint surfaces

What is rigor mortis?

stiffening of muscles after death

Why does rigor mortis occur?

no ATP is available to release attached actin and myosin molecules, calcium ion channels are left opened

How are muscles named?

Location, Origin, Insertion, Action, Size, Relative Location, Shape and direction of the fibers

What is range of motion (ROM)?

the degrees/angle through which a joint can move

How can you measure range of motion?

goniometer

What is adduction movement?

movement towards the midline of the body

What is abduction movement?

Movement away from the midline of the body

What is circumduction?

Moving in a circle at a joint (ex. swinging arm in circle)

What is rotation movement?

movement of a bone around its longitudinal axis

What is extension movement?

Increasing the angle of a joint

What is flexion movement?

bending movement that decreases the angle of the joint

What is plantar flexion?

bending the foot and toes downward

What is dorsiflexion?

flexing the foot and toes upward

What is supination?

turning the forearm so the palm is up

What is pronation?

turning the forearm so that the palm is down

What are the 6 types of synovial joints?

plane, hinge, pivot, condyloid, saddle, ball and socket

function of plane joint

allow the bones to slide or rotate against each other

example of plane joint

intercarpal and intertarsal joints

function of hinge joint

allowing flexion and extension in one plane with small degrees of motion in other planes

example of hinge joint

elbow and knee

function of pivot joint

permits movement of the bones in one plane, such as rotation around a single axis

example of pivot joint

neck

Function of a condyloid joint

allows for flexion, extension, abduction, and adduction movements

Example of condyloid joint

Wrist

function of ball and socket joint

provides swinging and rotating movements

Example of ball and socket joint

Shoulder and hip joints

function of saddle joint

allows movements on two planes-flexion or extension and abduction or adduction

Example of saddle joint

carpometacarpal of thumb