Muscles

Question 1

What are the three types of muscle tissues?

Answer 1

Skeletal, cardiac, and smooth

Question 2

How do the three muscle groups differ?

Answer 2

Cell structure, body location, how they are stimulated to contract

Question 3

All muscles are…

Answer 3

elongated

Question 4

What are the muscle cells called?

Answer 4

Muscle fibers

Question 5

How many muscles are there in the body?

Answer 5

600

Question 6

What do the muscle fibers do?

Answer 6

Have the ability to shorten or contract

Question 7

What is in the muscle fibers to make them contract?

Answer 7

Two types of myofilaments

Question 8

What does myo mean?

Answer 8

Muscle

Question 9

What are the muscle filaments equivalent to?

Answer 9

The microfilaments of the cytoskeleton

Question 10

What does sarco mean and what does it refer to?

Answer 10

Flesh, the muscle

Question 11

What is the cytoplasm of a muscle cell called?

Answer 11

Sarcoplasm

Question 12

Where are the skeletal muscles attached to?

Answer 12

The body’s skeleton

Question 13

What do the skeletal muscles do to the look of the body?

Answer 13

Give it a smoother contour

Question 14

What do muscle fibers look like?

Answer 14

Shaped like cigars, multinucleated cells, the largest type of the muscle fiber type

Question 15

What are skeletal muscles also called and why?

Answer 15

Striated muscles, its fibers appear to be striped

Question 16

What is the sarcolemma and what can be seen just beneath it?

Answer 16

Plasma membrane in muscle cells, many oval nuclei

Question 17

What are the myofibrils?

Answer 17

The nuclei are pushed aside by these long ribbon-like organelles

Question 18

What do the myofibrils do?

Answer 18

Give the muscle cell its striped appearance

Question 19

What are the two types of thread? What colors are they?

Answer 19

Myosin (dark)
Actin (light)

Question 20

What is myosin?

Answer 20

The protein that makes up the thick myosin filaments

Question 21

What does myosin have?

Answer 21

ATP enzymes

Question 22

WHat does ATP do?

Answer 22

Generates the power for muscle contraction

Question 23

WHat does calcium do?

Answer 23

Provides the final “go” signal for contraction

Question 24

What are the important key words for describing cardiac muscle?

Answer 24

Cardiac, striated, involuntary

Question 25

How are cardiac fibers arranged?

Answer 25

Cushioned by small amounts of connective tissue arranged in spiral or figure 8 shaped bundles

Question 26

Where is the frontalis and what does it do?

Answer 26

Covers the frontal bone and allows for the raising of the brows

Question 27

What are the orbicularis oculi and what do they do?

Answer 27

Fibers that run in circles around the eyes. Closing of the eyes, squinting, blinking, winking

Question 28

What is the buccinator and what does it do?

Answer 28

A fleshy muscle that runs horizontally across the cheek and inserts into the orbicularis oris. It flattens the cheek (as in whistling)

Question 29

What does the buccinator also do?

Answer 29

It is also a chewing muscle because it compresses the cheek to hold the food between the teeth during chewing

Question 30

What is the orbicularis oris and what does it do?

Answer 30

The circular muscles of the lips, this is often called the “kissing muscle” because it closes the mouth and protrudes the lips

Question 31

What is the zygomaticus and what does it do?

Answer 31

Extends from the corner of the mouth to the cheek bone, referred to as the “smiling muscle”, it raises the corners of the mouth upward

Question 32

What is the masseter and what does it do?

Answer 32

Covers the angle of the lower jaw as it runs from the zygomatic process of the temporal bone to the mandible, this muscle closes the jaw by elevating the mandible, masticating (chewing) muscle

Question 33

What is the temporalis and what does it do?

Answer 33

A fan shaped muscle overlying the temporal bone. It insterts into the mandible and acts as a synergist (enhances the effectiveness) of the masseter in closing the jaw

Question 34

What is the platysma and what does it do?

Answer 34

A single sheet like muscle that covers the anterior lateral neck. It originates from the connective tissue covering of the chest and inserts into the area around the mouth. Its action is to pull the corners of the mouth inferiorly, producing a downward sag of the mouth

Question 35

How does the sternocleidomastoid muscle work and what does it do?

Answer 35

When they contract, they flex your neck. This allows for the bowing of the head, sometimes called “prayer” muscles

Question 36

What is the pectoralis major?

Answer 36

A large fan shaped muscle covering the upper part of the chest, its origin is from the shoulder girdle and the first six ribs

Question 37

How does exhalation work?

Answer 37

The internal intercostal muscles, which lie deep to the external intercostals, depress the rib cage

Question 38

What are the 4 muscles of the abdominal girdle?

Answer 38

Rectus abdominus, external oblique, internal oblique, transverses abdominis

Question 39

Where are the trapezius muscles and what do they do?

Answer 39

They extend the head (the opposite of the sternocleidomastoids). They can also elevatem depress, adduct, and stabilize the scapula

Question 40

What are the latissimus dorsi and what do they do?

Answer 40

Large flat muscles that cover the lower back, extends and adducts the humerus

Question 41

Why are the latissimus dorsi important?

Answer 41

Are important when the arms must be brought down, like when swimming or sledge hammering

Question 42

What are the deltoid muscles?

Answer 42

Fleshy, triangle-shaped muscles that form the rounded shape of your shoulders, the origin winds across the shoulder girdle from the spine of the scapula to the clavicle, it inserts into the proximal humerus

Question 43

What is important about the deltoid muscles?

Answer 43

Because of the bulk sizem they are a favorite location for the injection of small amounts of medications (less than 5ml)

Question 44

What do the deltoids do?

Answer 44

Prime movers of arm abduction