biology chapter 10

Question 1

muscoskeletal system

Answer 1

forms the basic internal framework of the vertebrate body

Question 2

flagella

Answer 2

achieve movement by means of the power stroke, a thrusting movement generated by the sliding action of microtubules

Question 3

exoskeleton

Answer 3

is a hard skeleton that covers all muscles and organs of some invertebrates

Question 4

endoskeleton

Answer 4

serves as the framework within all vertebrate organisms. Also provides protection by surrounding delicate vital organs in bone

Question 5

cartilage

Answer 5

is a type of connective tissue that is softer and more flexible than bone.

Question 6

bone

Answer 6

is a specialized type of mineralized connective tissue that has the ability to withstand physical stress

Question 7

compact bone

Answer 7

is dense bone that does not appear to have any cavities when observed with the naked eye

Question 8

spongy bone

Answer 8

is much less dense, and consists of an interconecting lattice of bony spicules (trabeculae); the cavities in between the spicules are filled with yellow and/or red bone marrow

Question 9

yellow marrow

Answer 9

is inactive and infiltrated by adipose tissue

Question 10

red marrow

Answer 10

is involved in blood cell formation

Question 11

osteoblasts

Answer 11

synthesize and secrete the organic constituents of the bone matrix; once they have become surrounded by their matrix, they mature into osteocytes

Question 12

osteoclasts

Answer 12

are large multinucleated cells involved in bone resorption

Question 13

bone formation

Answer 13

occurs by either endochondral ossification or by intramembranous ossification

Question 14

endochondral ossification

Answer 14

existing cartilage is replaced by bone

Question 15

intramembranous ossification

Answer 15

mesenchymal (embryonic, undifferentiaated) connective tissue is tranformed into, and replaced by, bone

Question 16

axial skeleton

Answer 16

is the basic framework of the body, consisting of the skull, vertebral column, and the rib cage

Question 17

appendicular skeleton

Answer 17

which includes the bones of the appendages and the pectoral and pelvic girdles

Question 18

sutures

Answer 18

or immovable joints hold the bones of the skull together

Question 19

movable joints

Answer 19

bones that do move relative to one another

Question 20

ligaments

Answer 20

serve as bone to bone connectors

Question 21

tendons

Answer 21

attach skeletal muscle to bones and bend the skeleton at the movable joints

Question 22

origin

Answer 22

the point of attachment of a muscle to a stationary bone (the proximal end in limb muscles)

Question 23

insertion

Answer 23

the point of attachment of a muscle to the bone that moves (distal end in limb muscles)

Question 24

extension

Answer 24

indicates a straightening of a joint while flexion refers to a bending of a joint

Question 25

skeletal muscle

Answer 25

is responsible for voluntary movements and is innervated by the somatic nervous system. Has striations of light and dark bands, and is therefore also referred to as striated muscle

Question 26

myofibrils

Answer 26

are enveloped by a modified endoplasmic reticulum that stores calcium ions and called the sarcoplasmic reticulum

Question 27

sarcoplasm

Answer 27

the cytoplasm of a muscle fiber

Question 28

sarcolemma

Answer 28

cell membrane . Is capable of propagating an action potential, and is connected to a system of transverse tubules (T system) oriented perpendicularly to the myofibrils

Question 29

sacromere

Answer 29

is composed of thin and thick filaments

Question 30

thin filaments

Answer 30

are chains of actin molecules

Question 31

thick filaments

Answer 31

are composed of organized bundles of myosin molecules

Question 32

Z line

Answer 32

define the boundaries of a single sacromere and anchor the thin filaments

Question 33

M line

Answer 33

runs down the center of the sarcomere

Question 34

I band

Answer 34

is the region containing thin filaments only

Question 35

H zone

Answer 35

is the region containing thick filaments only

Question 36

A band

Answer 36

spans the entire length of the thick filaments and any overlapping portions of the thin filaments

Question 37

neuromuscular junction

Answer 37

the link between the nerve terminal (synaptic bouton) and the sarcolemma of the muscle fiber

Question 38

simple twitch

Answer 38

is the response of a single muscle fiber to a brief stimulus at or above the threshold stimulus, and consists of a latent period, a contraction period, and a relaxation period

Question 39

latent period

Answer 39

is the time between stimulation and the onset of contraction

Question 40

relaxation period

Answer 40

in which the muscle is unresponsive to a stimulus

Question 41

tonus

Answer 41

is a state of partial contraction. Muscles are never completely relaxed and maintain a partially contracted state at all times

Question 42

smooth muscle

Answer 42

is responsible for involuntary actions and is innervated by the autonomic nervous system. Is found in the digestive tract, bladder, uterus, and blood vessel walls, among other places

Question 43

cardiac muscle fibers

Answer 43

possess characteristics of both skeletal and smooth muscle fibers.

Question 44

creatine phosphate

Answer 44

energy can be temporarily stored in a high energy compound called creatine phosphate

Question 45

myoglobin

Answer 45

is a hemoglobin-like protein found in muscle tissue. Has a high oxygen affinity and maintains the oxygen supply in muscles by binding oxygen tightly