Chapter 1: Structure and Function of Body Systems

Question 1

axial skeleton

Answer 1

consists of the skull
(cranium), vertebral column (vertebra C1 through the
coccyx), ribs, and sternum

Question 2

appendicular skeleton

Answer 2

includes the shoulder (or pectoral) girdle (left and
right scapula and clavicle); bones of the arms, wrists,
and hands (left and right humerus, radius, ulna, carpals,
metacarpals, and phalanges); the pelvic girdle (left and
right coxal or innominate bones); and the bones of the
legs, ankles, and feet (left and right femur, patella, tibia,
fibula, tarsals, metatarsals, and phalanges).

Question 3

Fibrous joints

Answer 3

(e.g., sutures of the skull) allow virtually no movement

Question 4

cartilaginous joints

Answer 4

s (e.g., intervertebral disks) allow
limited movement

Question 5

synovial joints

Answer 5

(e.g., elbow and knee) allow considerable movement

most important features are low friction and large range of motion.

Question 6

hyaline cartilage

Answer 6

Covers articulating bone ends

Question 7

Uniaxial joints

Answer 7

such as the elbow, operate as hinges, essentially rotating about only one axis

Question 8

Biaxial joints

Answer 8

such as the ankle and wrist, allow movement about two
perpendicular axes.

Question 9

Multiaxial joints

Answer 9

including the shoulder and hip ball-and-socket joints, allowing movement about all three perpendicular axes that define space

Question 10

vertebral column

Answer 10

made up of vertebral bones
separated by flexible disks that allow movement to occur.

The vertebrae are grouped into 7 cervical vertebrae in
the neck region;

12 thoracic vertebrae in the middle to upper back;

5 lumbar vertebrae, which make up the lower back;

5 sacral vertebrae, which are fused together and make up the rear part of the pelvis

3 to 5 coccygeal vertebrae

Question 11

epimysium

Answer 11

Fibrous connective tissue that covers the body’s more than 430 skeletal muscles

The contiguous with the tendons at the ends of the muscle

Question 12

Where does the tendon attach?

Answer 12

The tendon is attached to bone periosteum, a specialized connective tissue covering all bones; any contraction of the muscle pulls on the tendon and, in turn, the bone

Question 13

perimysium

Answer 13

Surrounds fasciculi (muscle fiber bundles)

Question 14

endomysium

Answer 14

Surrounds individual muscle fibers

encircled by and is contiguous
with the fiber’s membrane, or sarcolemma

Question 15

motor unit

Answer 15

A motor neuron and the muscle fibers it innervates

All the muscle fibers of a motor
unit contract together when they are stimulated by the
motor neuron.

Question 16

sarcoplasm

Answer 16

the cytoplasm of a
muscle fiber, contains contractile components consisting of protein filaments, other proteins, stored glycogen and fat particles, enzymes, and specialized organelles such as mitochondria and the sarcoplasmic reticulum

Question 17

Two primary types of myofilament

Answer 17

myosin and actin

Question 18

Sarcomere

Answer 18

The smallest contractile unit of skeletal muscle

Question 19

A-band

Answer 19

corresponds with the alignment of the myosin filaments

Question 20

I-band

Answer 20

corresponds with the areas in two adjacent sarcomeres that contain only actin filaments

Question 21

Z-line

Answer 21

in the middle of the I-band
and appears as a thin, dark line running longitudinally through the I-band

Question 22

H-zone

Answer 22

The area in the center of the sarcomere where only myosin filaments are present. During muscle contraction, the H-zone decreases as the actin slides over the myosin toward the center of the sarcomere

Question 23

What ions control muscular contraction?

Answer 23

The regulation of calcium controls muscular contraction.

Calcium ions are stored in
the vesicles

Question 24

T-tubules