Lab: Muscles

Question 1

Muscle cell

Answer 1

Muscle fibers

Question 2

What causes muscle fibers to contract?

Answer 2

When action potential (stimulus) travels down the neuron to the skeletal muscle fiber

Question 3

The more fibers that contract…

Answer 3

The greater degree of contraction of the muscle as a whole

Question 4

The number of fibers determines…

Answer 4

degree of contraction

Question 5

Fascicles

Answer 5

The organized subunit of skeletal muscle fibers

Question 6

Each fascicle has…

Answer 6

1. Several muscle fibers (cells)
2. Connective tissue: ENDOMYSIUM & PERIMYSIUM

Question 7

Tendon is a combination of

Answer 7

Endomysium, perimysium, & epimysium

Question 8

Smooth muscle functions

Answer 8

1. Blood vessels constrict
2. Ingested food gets pushed along
3. Urinary bladder empties

Question 9

What muscles have striations?

Answer 9

Skeletal & cardiac muscle

Question 10

Skeletal muscle have what kind of cells?

Answer 10

Long, cylindrical & multinucleate

Question 11

Skeletal muscles have what kind of muscle?

Answer 11

Voluntary

Question 12

Smooth muscles have what kind of cells

Answer 12

Short, branched, & single nucleus

Question 13

Smooth and cardiac muscle have what kind of muscle?

Answer 13

involuntary

Question 14

Intercalated discs

Answer 14

Are heavily staining junctions where one cardiac muscle cell connects another

Question 15

Origin

Answer 15

The end of the muscle that ATTACHES TO THE BONE THAT DOES NOT MOVE

Question 16

Insertion

Answer 16

The end of the muscle that ATTACHES TO THE BONE THAT DOES MOVE

Question 17

Agonist

Answer 17

Muscle PERFORMS desired movement

Question 18

When flexing the elbow what muscle is the agonist & antagonist?*

Answer 18

Agonist- Brachialis
Antagonist- Triceps Brachii

Question 19

When extending the elbow what muscle is the agonist & antagonist?*

Answer 19

Agonist- Triceps Brachii
Antagonist- Brachialis

Question 20

Antagonist

Answer 20

Muscle OPPOSES desired movement

Question 21

Flexion

Answer 21

Bending a joint

Question 22

Extension

Answer 22

Straightening a joint

Question 23

Abduction

Answer 23

Moving a body part AWAY from midline

Question 24

Adduction

Answer 24

Moving a body part TOWARD the midline

Question 25

Elevation

Answer 25

Raising a body part

Question 26

Depression

Answer 26

Lowering a body part

Question 27

Rotation

Answer 27

Moving a body part around an axis

Question 28

Protraction*

Answer 28

Moving a body part ANTERIORLY

Question 29

Retraction*

Answer 29

Moving a body part POSTERIORLY

Question 30

Pronation

Answer 30

Turning palm posteriorly or facing down when arm held out

Question 31

Supination

Answer 31

Turning palm anteriorly or facing up when arm held out

Question 32

Circumduction

Answer 32

Circular (conical) movement as in shoulder, several actions involved

Question 33

Opposition

Answer 33

Opposable thumb, for use of tools

Question 34

Inversion

Answer 34

Turning the sole of the foot inward

Question 35

Eversion

Answer 35

Turning the sole of the foot outward

Question 36

Dorsiflexion

Answer 36

Flexing ankle superiorly toward the shin

Question 37

Plantarflexion

Answer 37

Extending ankle inferiorly toward the ground, pointing toes

Question 38

Muscles are named based on...

Answer 38

1. Direction of muscle fibers 2. Location 3. Shape 4. Origins and Insertions 5. Number of Origins 6. Action

Question 39

The direction of muscle fibers

Answer 39

1. Rectus = Straight 2. Transverse = Horizontal 3. Oblique = Diagonal

Question 40

Shape

Answer 40

Deltoid = Triangular, Trapezius = Trapezoid, Longus = Long