Unit 1 I Flashcards Preview

human anatomy I > Unit 1 I > Flashcards

Flashcards in Unit 1 I Deck (74):
1

Portion of the skeleton that forms the central axis of the body; skull, vertebral column, and bony thorax

Axial skeleton

2

Bones of the limbs and limb girdles that are attached to the axial skeleton

Appendicular skeleton

3

Vertical plane that divides the body into anterior and posterior parts

Frontal plane

4

Horizontal plane that runs from left to right, dividing the body into superior and inferior parts

Transverse plane (cross-section)

5

A vertical plane that divides the body or a body part into right and left portions

Sagittal plane

6

Specific sagittal plane that lies exactly in the midline

median plane (all others are parasagittal)

7

Cuts made along any plane that lies diagonally between the horizontal and vertical are called

oblique sections

8

Toward the head end or upper part of a structure or the body; above

superior

9

Away from the head end or toward the lower part of a structure or the body; below

inferior

10

Toward or at the middle of the body; on the inner side of

medial

11

away from the midline of the body; on the outer side of

lateral

12

closer to the origin of the body part or the point of attachment of a limb to the body trunk

proximal

13

farther from the origin of a body part or the point of attachment of a limb to the body trunk

distal

14

on the same side

ipsilateral

15

on opposite side

contralateral

16

toward or at the front of the body; in front of

anterior

17

toward the back of the body; behind

posterior

18

toward or at the body surface

superficial

19

away from the body surface; more internal

deep

20

a joint in which bones are united only by a ligament

syndesmosis

21

two types of cartilaginous joints are

synchondroses and symphyses

22

a joint where hyaline cartilage unites the bones

synchondrosis

23

a joint where fibrocartilage unites the bones

symphysis

24

freely movable joint with a cavity and a capsule

synovial joint

25

spongy cartilage in synovial joints

articular cartilage

26

the capsule of a synovial joint; consists of an outer layer of fibrous connective tissue and an inner synovial membrane

articular capsule

27

fluid secreted by the synovial membranes of the freely movable joints of the body; lubricates the joints surfaces and nourishes that articular cartilages.

synovial fluid

28

a disc of fibrocartilage in some synovial joints; occurs in joints whose articulating bone ends have somewhat different shapes

articular disc; meniscus

29

a fibrous sac lined with synovial membrane and containing synovial fluid; occurs between bones and tendons where it acts to decrease friction during movement

bursa

30

essentially and elongated bursa; it occurs only on tendons that are subjected to friction

tendon sheath

31

sliding the flat surfaces of two bones across each other

gliding

32

decreasing the angle between two bones

flexion

33

increasing the angle between two bones

extension

34

moving a limb away from the body midline

abduction

35

moving a limb toward the body midline

adduction

36

moving a limb or finger so that it describes a cone in space

circumduction

37

turning a bone around the longitudinal axis

rotation

38

rotating toward the medial plane

medial rotation

39

rotating away from the medial plane

lateral rotation

40

occurs when the forearm rotates laterally so that the palm faces on anteriorly (on its back)

supination

41

occurs when the forearm rotates medially so that the palm faces face down

pronation

42

roll ankle inward

inversion

43

roll ankle outward

eversion

44

point foot down

plantar flexion

45

point foot up

dorsiflexion

46

adjoining bones do not move around a specific axis

nonaxial

47

movement occurs around a single axis

uniaxial

48

movement can occur around two sacs; thus, the joint enables motion along both the frontal and sagittal planes

biaxial

49

movement can occur around all three axes and along all three body planes: frontal, sagittal, and transverse

multiaxial

50

synovial joints are classified as .... (6)

plane, hinge, pivot, condylar, saddle, and ball-and-socket

51

stability of synovial joints depends on three factors

shapes of articular surfaces, number and position of ligaments, muscle tone

52

a ligament can stretch only about ___ % beyond its normal length before it snaps

6%

53

an outer layer of dense, irregular connective tissue surrounds the whole skeletal muscle

epimysium

54

surrounding each fascicle is a layer of fibrous connective tissue called

perimysium

55

muscle fibers are separated into small groups called

fascicle

56

within a fascicle, each muscle fiber is surrounded by a fine sheath of loose connective tissue consisting mostly reticular fibers

endomysium

57

the connective tissue structure that joins skeletal muscle to bones

tendon

58

the attachment of the muscle on the less movable bone is called

origin

59

the attachment of the muscle on the more movable bone called

insertion

60

fibrous sheet connecting a muscle to the body part it moves

aponeurosis

61

a motor neuron and all the muscle fibers it innervates are called a

motor unit

62

the average number of muscle fibers in a motor unit

150

63

the addition of motor units to accomplish a movement is called

recruitment

64

skeletal muscle fibers can shorten by up to ____ of their resting length as they contract

1/3rd

65

when the effort arm is longer than the load arm, the lever operates at a mechanical advantage; when the effort arm is shorter than the load arm, the lever operates at a mechanical disadvantage

law of levers

66

arrangement of the elements is load-fulcrum-effort

first-class lever

67

arrangement of the elements is fulcrum-load-effort

second-class lever

68

arrangement of the elements is load-effort-fulcrum

third-class lever

69

all muscles develop from the _____ layer

mesoderm germ

70

in a development based scheme, muscles are organized into four groups

muscles of the visceral organs, pharyngeal arch muscles, axial muscles, and limb muscles

71

a muscle that has the major responsibility for producing a specific movement is the

prime mover (agonist)

72

muscles that oppose or reverse a particular movement are

antagonists

73

help the prime movers either by adding a little extra force to the movement being carried out or by reducing undesirable extra movements that the prime mover may produce

synergists

74

muscle that immobilizes one or more bones, allowing other muscles to act from a stable base

fixator