Muscle, Bone, and Skin

Question 1

3 types of muscle tissue

Answer 1

skeletal, cardiac, smooth

Question 2

4 functions of muscle

Answer 2

body movement
stabilization of body position
movement of substances through body
generating heat to maintain body temp

Question 3

tendon vs. ligament

Answer 3

tendon: muscle to bone
ligament: bone to bone

Question 4

agonist vs. antagonist

Answer 4

agonist: muscle responsible for movement, contracts
antagonist: stretches

Question 5

synergistic muscles

Answer 5

assist the agonist by stabilizing the origin bone or by positioning the insertion bone during movement

Question 6

smallest functional unit of skeletal muscle

Answer 6

sarcomere

Question 7

____ is multinucleate

Answer 7

skeletal muscle

Question 8

sarcolemma

Answer 8

modified membrane, wraps several myofibrils together to form a muscle cell or muscle fiber

Question 9

thick filament of sarcomere made of

Answer 9

myosin

Question 10

thin filament of sarcomere made of

Answer 10

actin

Question 11

each ____ head crawls along the ____

Answer 11

each myosin head crawls along the actin in a 5 stage cycle

Question 12

ER of muscle cell

Answer 12

sarcoplasmic reticulum
surrounds each myofibril
lumen filled with Ca2+ ions

Question 13

in the presence of Ca2+ ions…

Answer 13

troponin pulls the tropomyosin back, exposing the active site, allowing the myosin head to bind to the actin

Question 14

neuromuscular synapse

Answer 14

neuron attaches to muscle cell

Question 15

action potential of neuron releases ____ into the synaptic cleft

Answer 15

acetylcholine - activates ion channels in sarcolemma creating action potential

Question 16

T-tubules

Answer 16

allow for a uniform contraction of the muscle by allowing the action potential to spread through the muscle cell more rapidly

Question 17

action potential transferred to the sarcoplasmic reticulum and….

Answer 17

becomes permeable to Ca2+

Question 18

a motor unit consists of…

Answer 18

a nerve and all the muscle fibers it synapses with

Question 19

___ motor units are the first to be activated

Answer 19

small motor units activate first, larger motor units recruited as needed –> smooth increase in force gener ated by muscle

Question 20

myoglobin

Answer 20

oxygen storing protein similar to hemoglobin
only 1 protein subunit
make slow twitch muscle fibers (type 1) red

Question 21

type 1/slow twitch muscle fibers

Answer 21

red from myoglobin
lots of mitochondira
flow to fatigue, slow contraction velocity

Question 22

type 2 A/fast twitch A fibers

Answer 22

red, split ATP at high rate
contract rapidly
resistant to fatigue but not as resistant as type 1

Question 23

type 2 B fibers / fast twitch B fibers

Answer 23

low myoglobin, appear white
contract very rapidly
large amounts of glycogen

Question 24

muscle cells and mitosis

Answer 24

lost ability to undergo mitosis

hypertrphy: diameter of fibers increases, number of sarcomeres and mitochondria increase, sarcomeres lengthen

Question 25

striated

Answer 25

composed of sarcomeres

skeletal and cardiac muscle

Question 26

each cardiac muscle cell contains ____ nucus

Answer 26

one

Question 27

intercalated disc

Answer 27

separate cardiac muscle cells

contain gap junctions which allow an action potential to spread from cell to cell

Question 28

action potential of cardiac muscle exhibits a ____ after depolarization

Answer 28

plateau created by slow voltage gated calcium channels which allow calcium to enter and hold the inside of the membrane at a positive potential difference
plateau lengthens the time of contraction

Question 29

smooth muscle mainly innervated by the …

Answer 29

autonomic nervous system, mainly involuntary

Question 30

smooth muscle cells contain ___ nucleus

Answer 30

one

Question 31

smooth muscles contain intermediate filaments which are attached to ___ ___

Answer 31

dense bodies

Question 32

single unit smooth muscle/visceral

Answer 32

most common; arteries, veins, stomach,intestines, uterus, bladder
connected by gap junctions, single neuron to large group of cells

Question 33

multiunit smooth muscle fibers

Answer 33

each attached directly to a neuron, can contract independently of other fibers in same location
large arteries, bronchioles, pili muscles attached to hair follicles, iris

Question 34

bone functions

Answer 34

support, protection, movement

*mineral storage, blood cell production, energy storage in form of adipose cells in marrow

Question 35

osteoblasts

Answer 35

secrete collagen and organic compounds upon which bone is formed
no mitosis, differentiate into osteocytes

Question 36

osteocytes

Answer 36

exchange nutrients and waste materials with blood, no mitosis

Question 37

osteoclasts

Answer 37

resorb bone matrix, releasing minerals back into the blood, develop from monocytes

Question 38

spongy bone contains…

Answer 38

red bone marrow - site of red blood cell development

Question 39

compact bone contains…

Answer 39

yellow bone marrow - has adipose cells for fat storage

Question 40

Haversian (central) canals

Answer 40

compact bone, osteoclasts burrow tunnels

Question 41

lamellae

Answer 41

concentric rings from osteoblasts lay down new matrix onto tunnel walls of central canals

Question 42

canaliculi

Answer 42

for osteocyctes trapped between lamellae to exchange nutrients

Question 43

Volkmann’s canals

Answer 43

crossing canals that connect blood and lymph vessels in the Haversian canals

Question 44

osteon / Haversian system

Answer 44

entire system of lamellae and Haversian canal

Question 45

most of the Ca2+ in the body is stored in the bone matrix as ____

Answer 45

hydroxyapatite, give great compressive strength

Question 46

cartilage composed primarily of ….

Answer 46

collagen, great tensile strength

no blood vessels or nerves except in its outside membrane (perichondrium)