A&P unit 4 chapter 10 muscle tissue test review

recognized functions of skeletal muscle

produce skeletal movement, maintain body position, support soft tissue, guard openings, maintain body temp, store nutrient reserves

layers of connective tissue that surround skeletal muscles (in —> out)

endomysium, perimysium, epimysium

endomysium

surrounds individual muscle cells (muscle fibers), contains capillaries and nerve fibers, contains myosatellite / stem cells for damage repair

perimysium

surrounds muscle fiber bundles (fascicles), contains blood vessels and nerve supply to fascicles

epimysium

the exterior collagen layer of a skeletal muscle connected to the fascia, separates muscle from surrounding tissue

ligament

fibrous connective tissue that connects bone to bone

tendon

fibrous connective tissue that connects muscle to bone / other body structures

Why does skeletal muscle have so many nuclei?

because they're formed from the fusion of embryonic myoblasts

tropomyosin

double strand, prevents actin-myosin interaction

actin-myosin interaction

muscle contraction

A band

alternating dark, thick filaments of muscle striation

I band

light, thin filaments of muscle striation

M line

the center of an A band, at midline of a sarcomere

Z line

the center of an I band, at the two ends of a sarcomere

tension

when muscle fibers pull together in muscle contraction

relaxation

the second part of muscle contraction, when the muscle fibers lose tension

motor unit

single motor neuron and all the muscle fibers it innervates

concentric

isotonic contraction in which muscle tension > than the load (resistance), and the muscle shortens

eccentric

isotonic contraction in which muscle tension < load (resistance), and the muscle lengthens

isotonic contraction

type of skeletal muscle tension in which the muscle changes length, resulting in motion

isometric contraction

type of skeletal muscle tension in which the muscle develops tension but is prevented from changing in length

What can mitochondria provide at peak muscle exertion?

about 1/3 of the energy required by the muscle

pennate

symmetrical on both sides

convergent

coming closer together

divergent

getting farther apart

parallel

lying or moving in the same direction but always the same distance apart

synergist

incentive, motivation, stimulus, etc

prime mover

the muscle that provides the primary driving force for an action

muscle origin

the muscle attachment site that doesn't move during contraction

muscle insertion

the muscle attachment that moves during contraction

internus

extending toward the interior

extrinsic

(muscle) originates some distance from what it moves

profundus

deep

rectus

straight

proximal

close

intrinsic

contained wholly within the organ on which it acts (opposite of extrinsic)

superficialis

near the surface