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Flashcards in Muscles of the body Deck (61):
1

Most skeletal muscles run from one _____ to another.

bone

2

What is the origin of a muscle?

- Less movable attachment of a muscle
- start

3

What is the insertion of a muscle?

The more movable attachment of a muscle
- end

4

The ________ of the muscle moves towards the _______.

insertion towards origin

5

Skeletal muscles are arranged into ________.

fascicles

6

What are fascicles?

Bundle of fibres running parallel to one another.

7

How does fascicle arrangement allow one to determine?

Tells you about the action of the muscle.

8

What is the power of the muscle determined by?

1 - The number of muscle fibres in the muscle (more fibres means more power)

2 - Length of the fibres

9

What are the different, basic muscle types?

Parallel
- fusiform
- straplike
Circular
Triangular/convergent
Pennate
- unipennate
- bipennate
- multipennate

10

What are parallel muscles?

Fibres run parallel to the long axis of the muscle.

11

What are the two types of parallel muscles (i.e. where the fibres run parallel to the long axis of the muscle)?
Provide an example for each.

Fusiform - biceps brachii

Straplike - sartorius

12

Describe a fusiform muscle.

Parallel muscle
- central belly with two tapered ends

13

Describe a straplike muscle.

Parallel
- long, thin, strappy type muscle

14

Between both biceps brachii and sartorius, which would be more powerful?

Biceps brachii:
- bigger, thicker
- shorter muscle that can contract quicker

15

What does circular muscle do? Where would you find it?
Give an example.

Circular muscles help close any type of orifice.

ex: orbicularis oris - helps close the mouth

16

What does pennate mean?

Feather; fibres attach obliquely

17

What does unipennate mean?
Give an example muscle.

All the fascicles are one the same side of the tendon
ex: extensor digitum longus

18

What does bipennate mean?
Give an example muscle.

Fascicles on both sides of the central tendon
ex: rectus femoris

19

What does multipennate mean?

Multiple insertions in featherlike arrangement
ex: deltoid

20

"A muscles cannot reverse the movement it produces." Explain this.

When a muscle contracts and performs its movement, another muscles must undo the action.
These muscle with opposite actions will lie on opposite sides of a joint.

21

Whenever a muscle crosses a joint it....(finish the statement).

Performs an action on that joint.

22

What is a prime mover/Agonist?

Has a major responsibility for a certain movement.

23

What is an antagonist?

Opposes or reverses the movement of a prime mover.

24

What is a synergist?

Helps the prime mover.

25

How can a synergist help the prime mover?

1 - By adding extra force
2 - By reducing undesirable movements
3 - Stabilizing the prime mover

26

What is a fixator?

Type of synergist.
- Holds a bone/joint firmly in place
- Stabilizes the prime mover so it can act more efficiently

27

What are the different kinds of muscular contractions?

Concentric contraction
Eccentric contraction
Isometric contraction

28

What is concentric contraction?

Muscle shortens and does work

29

What is eccentric contraction?

Muscle generates force as it lengthens.
- resisting gravity - acts as a brake
- negative work

30

What is an example of an eccentric contraction?

Squats

31

What is DOMS, what is it caused by?

Delayed Onset Muscular Soreness.
Caused mostly by eccentric contraction since most of the muscle tears occur during eccentric contraction.

32

What are isometric contraction?

Contraction to stabilize, not shortening or lengthening.

33

How are muscles divided into compartments.

Dense regular CT divides limb muscles into compartments.

34

What are muscle compartments?

Group of skeletal muscles that arose from a common embryonic origin

35

The CT that divides muscles into compartments wraps after what layer?

The epimysium

36

Muscles in opposing compartments are what?
What do they share?

Agonist and antagonist pairs
Share a common blood and nerve supply

37

What are the different muscles compartments of the arm?
Give an example for both.

Anterior and posterior
A - biceps brachii
P - triceps brachii

38

What are the different muscle compartments of the thigh?

Anterior
Posterior
Lateral
Medial

39

What does the anterior compartment muscles of the arm do?
The posterior?

Anterior - flex the shoulder or elbow
Posterior - extend the shoulder or elbow

40

What does the anterior compartment of the thigh do?
Posterior?

Posterior (think hamstring curl)
- extends hip, flexes knee
- backswing phase of walking

Anterior (Think leg extension)
- flex the hip, extend the knee

41

What do the medial compartment muscles of the thigh do?
Lateral?

Medial
- adduct thigh

Lateral
- abduct thigh

42

There are 4 general rules for muscle actions as they cross a joint. What are they?

A muscle that crosses on the _______ side of joint produces ______.
1 - Anterior - flexion
2 - Posterior - extension
3 - Lateral - abduction
4 - medial - adduction

43

What are the different ways in which skeletal muscle can be named?

Location
Shape
Relative size
Direction of fascicles and muscle fibres.
Number of origins
Action

44

Give an example muscle who's name provides the location.

Brachialis - located on the arm

45

Give an example muscle who's name provides the shape.

Deltoid - triangular

46

Give an example muscle who's name provides the relative size

Gluteus maximus - large

47

Give an example muscle who's name provides the location of attachments.

Brachioradialis
first name is origin, second is insertion.
Origin - arm
insertion - radius

48

Give an example muscle who's name provides the number of origins.

Biceps - two

49

Give an example muscle who's name provides the action?

Extensor digitum longus
- extends fingers

50

Where is the origin and insertion of the external intercostal muscles?

External intercostals pull the ribcage up and out, insertion moves towards origin so,
Insertion on the bottom rib, origin on the upper rib

51

Where is the origin and insertion of the internal intercostal muscles?

Internal intercostals pull the ribcage down and in so,
insertion - top rib
origin - bottom rib

52

Where is the origin and insertion of the diaphgram?

When contracted, flattens, dome when relaxed so,
middle is insertion, origin is around edge.

53

How many muscles cross the shoulder joint and insert on the humerus?

Nine

54

What muscle can be injured when doing that cat back on the DL?

erector spinae

55

What are the chief forearm flexors?

Biceps and brachialis
brachialis is a synergist
biceps is the PM

56

What are the chief forearm extendors?

Triceps (PM) and anconeus (synergist)

57

Brevis means?

Short

58

Magnus means?

Large

59

The quadriceps femoris has 4 different _______. These are not _______.

heads
not origins

60

How does the tensor fasciae latae stabilize the trunk on the thigh?

Making IT band taut

61

Hamstrings cross the ___ and _____ joints on the ______ side.
This means they do what?

Hip and knee
Posterior
Flexes thigh and extends hip