Lesson 7

Question 1

fibrous joints

Answer 1

joined by fibrous tissues

Question 2

two major types of fibrous joints

Answer 2

sutures and syndesmoses

Question 3

fibrous joints: sutures

Answer 3

interlock bones of the skull

Question 4

fibrous joints: syndesmoses

Answer 4

articulating bones are connected by short ligaments

Question 5

cartilaginous joints

Answer 5

articulating bones are connected by cartilage plate or pad

Question 6

two major types of cartilaginous joints

Answer 6

symphyses and synchondroses

Question 7

cartilaginous joints: symphyses

Answer 7

bones connected by broad, flat, fibrocartilage discs

Question 8

cartilaginous joints: synchondroses

Answer 8

bony portions united by hyaline cartilage

Question 9

synovial joints are _____

Answer 9

diarthroses, aka free moving

Question 10

synovial joints

Answer 10

articulating bone ends separated by joint cavity filled with synovial fluid

Question 11

synovial joint: articular capsule

Answer 11

encloses the joint surface, is reinforced by ligaments; may contain bursae (fluid sacs); may contain fibrocartilage pads (articular discs)

Question 12

synovial joint: fibrous capsule

Answer 12

outer layer of dense irregular connective tissue

Question 13

synovial joint: articular (hyaline) cartilage

Answer 13

covers bone ends at the joint

Question 14

synovial joint: joint cavity

Answer 14

encompassed by articular cartilage (covers the epiphysis of bones) and synovial membrane; filled with synovial fluid

Question 15

synovial joint type: plane

Answer 15

flat surface
- intercarpal/tarsal joints

Question 16

synovial joint type: hinge

Answer 16

round end to concave surface
- elbow and interphalangeal joints

Question 17

synovial joint type: pivot

Answer 17

round/conical bone to shallow depression/foramen
- atlas and axis

Question 18

synovial joint type: condyloid/ellipsoidal

Answer 18

oval condyle to ellipsoidal depression
- radiocarpal joint and metacarpophalangeal joints

Question 19

synovial joint type: saddle

Answer 19

saddle shaped, one convex, one concave
- metacarpal and trapezium of the wrist

Question 20

synovial joint type: ball and socket

Answer 20

ball-shaped head fits into cup-like depression
- shoulder

Question 21

flexion

Answer 21

decreases the joint angle

Question 22

extension

Answer 22

increases the joint angle

Question 23

hyperextension

Answer 23

increase joint angle over 180 degrees

Question 24

abduction

Answer 24

limb away from midline

Question 25

adduction

Answer 25

limb towards midline

Question 26

rotation

Answer 26

movement around longitudinal axis

Question 27

circumduction

Answer 27

distal end moves in a circle

Question 28

pronation

Answer 28

palm from anterior to posterior

Question 29

supination

Answer 29

palm from posterior to anterior

Question 30

inversion

Answer 30

medial turn of the sole of the foot

Question 31

eversion

Answer 31

lateral turn of the sole of the foot

Question 32

dorsiflexion

Answer 32

ankle joint flexes upward to raise toes

Question 33

plantar flexion

Answer 33

ankle joint flexes downward to lower the toes (pointing your toes)

Question 34

muscel fibers

Answer 34

multinucleated cells

Question 35

myofibrils

Answer 35

contractile units; actin and myosin

Question 36

thin filaments

Answer 36

actin

Question 37

thick filaments

Answer 37

myosin

Question 38

sarcomere

Answer 38

smallest functional contractile unit of muscle (between two Z lines)

Question 39

transverse (T) tubule

Answer 39

indentation of the sarcolemma forms a tubule at the A/I band junction

Question 40

A band

Answer 40

region of sarcomere containing thick filaments (dark band)

Question 41

I band

Answer 41

regino of the sarcomere containing thin filaments (light band0

Question 42

sarcoplasmic reticulum

Answer 42

muscle cell's smooth endoplasmic reticulum, used to store calcium ions

Question 43

triad

Answer 43

structure consisting of two terminal cisterns of the sarcoplasmic reticulum and transverse tubule between them

Question 44

Z disc

Answer 44

the scaffolding of the I band (light band)

Question 45

H zone

Answer 45

space between two Z discs

Question 46

M line

Answer 46

scaffolding holding the thick filaments together

Question 47

endomysium

Answer 47

connective tissue that ensheaths muscle fibers

Question 48

perimysium

Answer 48

collagen membrane that bundles together ensheathed muscle fibers

Question 49

fascicle

Answer 49

bundles of muscle fibers and their endomysium and perimysium

Question 50

blood vessels feeding the muscles are found between individual _____

Answer 50

fascicles

Question 51

epimysium

Answer 51

dense connective tissue that fascicle bundles are held together by

Question 52

aponeuroses

Answer 52

flattened sheet of tendon

Question 53

what three things combine to form tendons?

Answer 53

extensions of the endomysium, perimysium, and epimysium

Question 54

motor unit

Answer 54

motor neuron and the muscles fibers it targets

Question 55

synaptic cleft

Answer 55

fluid filled gap between the nerve axon terminal and muscle fiber

Question 56

neuromuscular junction

Answer 56

area where a neuron's axon interacts with muscle cells

Question 57

muscle contraction: step 1

Answer 57

Release of a chemical transmitter called a neurotransmitter (acetylcholine) from the neuron’s synaptic terminal. The acetylcholine enters into the synaptic cleft (space between nerve and muscle)

Question 58

muscle contraction: step 2

Answer 58

cetylcholine signals the muscle fiber depolarizes (muscle fiber temporarily becomes positively charged)

Question 59

muscle contraction: step 3

Answer 59

Muscle depolarization causes Ca2+ release from the sarcoplasmic reticulum (located inside the muscle cell).

Question 60

muscle contraction: step 4

Answer 60

The released Ca2+ enters the inside of the muscle fiber and “unlocks” the thin filament so it can interact with the thick filament

Question 61

muscle contraction: step 5

Answer 61

Thick/thin filament are now able to interact and “slide along” each other, causing muscle contraction (this uses energy in the form of ATP)

Question 62

two ways muscle contraction force can be increased

Answer 62

1. motor unit recruitment: increasing the active number of motor units 2. increasing the stimulus frequency

Question 63

muscle contraction: latent phase

Answer 63

time between stimulation and beginning of contraction

Question 64

muscle contraction: contraction phase

Answer 64

myofilaments (thick/thin filaments) sliding

Question 65

muscle contraction: relaxation phase

Answer 65

end of contraction, muscle returns to normal length

Question 66

muscle fatigue

Answer 66

occurs from prolonged sustained muscle contraction; results from not enough energy (ATP) available for muscle contraction

Question 67

isometric contraction

Answer 67

muscle length does not change, force is different

Question 68

isotonic contraction

Answer 68

muscle length changes, force is the same