Chapter 11, Muscular System Flashcards Preview

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Flashcards in Chapter 11, Muscular System Deck (31):
1

Types of muscles

Parallel: biceps brachii
Convergent: pectoralis major, rectus abdominous, supinator
Pennare: rectus femoris, deltoid,
Circular: orbicularis oris

2

Parallel muscles

Fascicles are parallel to the long axis

3

Convergent muscles

Fascicles extent over a large surface area and converge at a common attachment point. Muscle fibers pull in different directions rather than one in parallel.

4

Pennate muscles

Form a common angle with their tendon and contract at an angle. Do not move their tendon as much as parallel muscles. Produce more tension because they contain more muscle fibers.
Unipennate
Bipennate
Multipennate

5

Circular muscles

Circularly located around an opening, also called sphincters and guard body openings

6

Purpose of a lever

Attaching to a muscle a lever can modify force, speed, or direction of movement.
A lever is a ridged structure such as bone-that moves on a fixed fulcrum

7

3 important things about levers

They can change:
1. direction of an applied force
2. distance and speed of movement produced by an applied force
3. effective strength of applied force

8

First class lever

Pry bar
Fulcrum lies between the applied force and the load
Example: neck

9

Origin

Fixed attachment to a bone, cartilage or connective tissue

10

Insertion

The site where the movable end attaches to another structure

11

Ways to define muscles based on their functions

Agonist
Antagonist
Synergist
Fixator

12

Agonist

Prime mover, a muscle whose contraction is mostly responsible for producing a movement

13

Antagonist

A muscle whose action opposes the action of an agonist

14

Synergist

Contracts to help a larger agonist work efficiently

15

Fixator

A synergist that assists an agonist by preventing movement at another joint, thereby stabilizing the origin of the agonist

16

Descriptive terms used to name skeletal muscle

Location in the body
Origin and insertion
Fascicle organization
Posisiton
Structural characteristics
Action

17

Muscles of the axial

Head and neck
Vertebral column
Oblique and rectus muscles
Pelvic floor

18

Second class lever

The load lies between the applied force and the fulcrum, wheelbarrow
Body example Heel lift

19

Third class lever

The applied force is between the load and the fulcrum, catapult
Biceps curl

20

Muscles of the mouth in facial expression

Buccinator: compresses cheeks
Depressor libii inferiois: depresses lower lip
Levator libii superiois: elevates upper lip
Levator anguli oris: smile muscle
Mentalis: elevated and prodrudes lowe lip ( pout muscle)
Orbicularis oris: compresses purses lips
Risorius: draws corner of the mouth to the side
Depressor anguli oris: depresses corner of the mouth
Zygomatic major: retracts and elevates corner if the mouth
Zygomatic minor: retracts and elevates upper lip

21

Muscles of the eye in facial expression

Corruegator supercilii: wrinkles eye brow
Levator papebrae superioris: elevates upper eye lid
Orbicularis oculi:closes eyes

22

Muscles of the nose in facial expression

Procerus: moves nose and changes position and shape of the nostrils
Nasalis: Compresses bridge, depresses tip of nose and elevates corners of nostrils

23

Muscle of the ear in facial expression

Temporoparietalis: tenses scalp, moves auricle of ear

24

Muscles of scalp in facial expression

Occipitofrontalis: raises eyebrows wrinkles forehead
Occipital belly: tenses and retracts scalp

25

Neck muscle in facial expression

Patysma: tenses skin of the neck; depresses mandible; pulls lower lip down.

26

Extrinsic eye muscles (6)

Inferior rectus: eye looks inferiorly
Medial rectus: eye looks medially
Superior rectus: eye looks superiorly
Lateral rectus: eye looks laterally
Inferior oblique: eye rolls, looks superior and laterally
Superior oblique: eye rolls, looks inferior and lateally

27

Muscles of mastication

Masseter: elevates mandible and jaw closes
Tepmoralis: elevates mandible
Medial Ptergoids: elevates mandible, slides mandible from side to side (lateral excursion)
Lateral Ptergoids: Open jaw, protrudes mandible or preforms lateral excursion

28

Muscles of the tongue

Genioglossus: depresses and protracts the tongue
Hypoglossus: depresses and retracts the tongue
Palatoglossius: elevates tongue and depresses soft pallet
Styloglossus: retracts the tongue and elevates the side of the tongue

29

Muscles of the pharynx

Pharyngeal constrictors (superior, middle and inferior): move food into the esophagus
Palatal muscles: tensor veli palatini and levator veli palatini:elevate spft pallet and pull open the enterence to the auditory tube

30

Rectus Muscles

Are important flexors of the vertebral column, acting in opposition to the erector spinae

31

Scalene muscles

elevate the first two ribs and assist in the flexion of the neck