A&P Lab Practical

origin

attached to less moveable

insertion

attached to more moveable

what muscles are found in the femoral triangle?

• adductor femoris

• adductor longus

• pectineus

adductor femoris + longus origin, insertion & action

• pubic symphysis

• femur

• adducts thigh

pectineus action

adducts thigh

what muscles are in the quadriceps femoris?

• rectus femoris

• vastus lateralis

• vastus medialis

• vastus intermedius

quadriceps femoris insertion + action

• patella & tibial tuberosity

• extends knee

rectus femoris action

extends knee + flexes hip

what muscles are in the hamstrings?

• biceps femoris

• semitendinosus

• semimembranosus

hamstrings origin + action

• ischial tuberosity

• flexes knee

what muscles are in the triceps surae?

• gastrocnemius

• soleus

• plantaris

triceps surae insertion + action

• calcaneus via calcaneal tendon

• plantar flexion

gluteus maximus + medius action

abducts thigh

tibialis anterior action

dorsiflexion

flexor digitorum longus action

flexes digits

extensor digitorum longus action

extends digits

clavotrapezius insertion

clavicle

acromiotrapezius insertion

acromion of scapula

spinotrapezius insertion

scapular spine

clavodeltoid origin + insertion

• clavicle

• deltoid tuberosity

acromiodeltoid origin + insertion

• acromion of scapula

• deltoid tuberosity

spinodeltoid origin

scapular spine

what muscles are in the rotator cuff?

• supraspinatus

• infraspinatus

• subscapularis

• teres minor

supraspinatus origin, insertion, action

• supraspinous fossa of scapula

• humerus- greater tubercle

• stabilizes humerus

infraspinatus origin, insertion, action

• infraspinous fossa of scapula

• humerus- greater tubercle

• laterally rotates + stabilizes humerus

subscapularis origin, insetion, action

• subscapular fossa

• humerus- lesser tubercle

• medially rotates + stabilizes humerus

levator scapulae ventralis insertion + action

• scapula

• elevates scapula

teres major origin + insertion

• inferior angle of scapula

• humerus

what muscles are found in the errector spinae?

• iliocostalis

• logissimus dorsi

• spinalis dorsi

biceps brachii origin, insertion, action

• scapula

• radial tuberosity

• flexes forearm

triceps brachii origin, insertion, action

• scapula + humerus

• ulna- olecranon process

• extends forearm

pectoantebrachialis origin + action

• manubrium of sternum

• adducts the humerus

pectoralis major + minor origin, insertion, action

• sternum

• humerus

• adducts the humerus

xiphihumeralis origin, insertion, action

• xiphoid process of sternum

• humerus

• adducts the humerus

external intercostals origin, insertion, action

• ribs

• ribs

• elevates ribs

internal intercostals origin, insertion & action

• ribs

• ribs

• depresses ribs

scalenes action

elevates ribs

what is linea alba?

connective tissue

masseter origin, insertion & action

• zygomatic arch

• mandible

• elevates mandible

digastric origin, insertion & action

• mandible

• hyoid bone

• depresses mandible

sternohyoid origin + insertion

• manubrium

• hyoid bone

sternomastoid origin, insertion & action

• manubrium

• mastoid process of temporal bone

• rotates head

what muscles are unique to cats? (not found in humans)

• caudofemoralis

• rhomboideus capitis

• pectoantebrachialis

• xiphihumeralis

• epitrochelaris

adductor femoris in cats

single large muscle

adductor femoris in humans

split into 2 muscles (adductor magnus + brevis)

gluteal muscles in cats

• smaller

• medius larger than maximus

gluteal muscles in humans

large, maximus forms most of buttocks, extends thigh

trapezius in cats

split into 3 muscles

trapezius in humnas

single muscle

deltoid in cats

split into 3 muscles

deltoid in humans

single muscle

biceps brachii in cats

only 1 head

biceps brachii in humans

2 heads (long + short)

sternocleidomastoid in cats

split into 2 msucles (sternomastoid + cleidomastoid)

sternocleidomastoid in humans

single muscle with 2 heads

rectus abdominis in cats

absent

rectus abdominis in humans

support/reinforce abdominal wall

why are there differences?

• humans are bipeds

• cats are quadrupeds

bipeds

walk on 2 legs

quadrupeds

walk on all 4s (use their upper limbs to walk)

what is this?

sarcolemma

what is this?

myofibril

what is this?

sarcoplasmic reticulum

sarcoplasmic reticulum

stores and releases calcium ions

what is this?

t-tubules

t-tubules

carry action potentials into muscle fiber

label A-H

• actin

• z disc

• h zone

• myosin

• I band

• A band

• sarcomere

• m line

label A-E

• z disc

• sarcomere

• m line

• actin

• myosin

myosin

thick filament

actin

thin filament

what happens to A band during contraction?

stays the same length

what happens to I band during contraction?

shortens

what happens to Z discs during contraction?

move closer together

label neuromuscular junction (slide view) A-C

• axon

• synaptic bulb of axon terminal

• striated muscle

label neuromuscualr junction (A-C)

• synaptic vesicles with Ach

• synaptic cleft

• motor end plate

motor neuron axon

carries nerve signal toward muscle

synaptic vesicles contain?

acetylcholine (ACh)

ACh function?

bind to receptors on motor end plate

muscle contraction producing enough tension to cause movement

isotonic contraction

muscle contraction that generates tension but does not produce skeletal movement

isometric contraction

which contraction generates greater force?

isometric

motor unit?

motor neuron and all muscle fibers it stimulates

motor neuron recruitment?

increasing number of active motor units

range of motion?

amount of possible movement at a joint

length-tension relationship?

force depends on muscle length

optimal sarcomere length?

80-120% of resting length

length-tension contraction type

isometric

length-tension instrument

hand dynamometer

what did length-tension lab measure?

grip strength

force-velocity relationship?

as load increases, shortening velocity decreases

higher shortening allows how much force?

less force

why is force lower at higher shortening velocity?

less time for cross-bridge format

force-velocity contraction type?

isotonic

How was force-velocity tested?

time a 90 degree contraction with different weights

why is warming a muscle prior to stretching/exercise important?

to prevent injury and improve muscle function

reasons why warming up improves muscle function

• increase blood flow

• faster chemical reactions

• decreased synovial fluid viscosity

what instrument measures ROM?

goniometer

how did we test effect of temperature on flexibility?

measure hamstring ROM before and after exercise

effect of exercise on flexibility?

ROM generally increases after warming up

what occupies most of the space in a skeletal muscle fiber?

myofibrils