Lab 10

Question 1

What are the identifiable histology structures of a skeletal muscle?

Answer 1

I-band, A-band, Z-disc, nucleus, cell

Question 2

What are the identifiable histology structures of a cardiac muscle?

Answer 2

Striations, intercalated disc, nucleus, and cell

Question 3

What are the identifiable histology structures of a smooth muscle?

Answer 3

Nucleus and cell

Question 4

What are the aspects of the somatic muscle model?

Answer 4

somatic motor neuron, endomysium, sarcolemma, nucleus, myofibril, sarcomere A-band, M-line, I-band, Z-disc

Question 5

What are the sections on a myofibril?

Answer 5

Sarcomeres:
Light band: “I band” only thin filaments attached to Z-disk
Dark band: “A band” thin and thick filaments overlap w/ faint M-line in the middle (what thick filaments attach to)

Question 6

Tell me about cardiac muscles:

Answer 6

Only found in heart,
involuntary control,
short, branched cells,
1-2 nuclei, striations: areas of contractile proteins running across shortest cell length,
intercalated disk between two cells-parallel to and thicker than striations

Question 7

Tell me about smooth muscles:

Answer 7

Generally surround hollow organs/tubes, but also found in other areas such as iris, ciliary muscle, arrector pili,
involuntary control,
short, pointed cells,
one long oval-shaped nucleus,
no striations

Question 8

Tell me about skeletal muscles:

Answer 8

Attach to bones,
voluntary control (with potential for involuntary control),
extremely long, cylindrical cells,
multinucleate, many nuclei found at the edge of the cell,
plasma membrane called sarcolemma,
contains myofibril organelles, 80% muscle cells, ++ long and cylindrical, contractile organelles, shortens by making contractile subunits (sarcomeres) closer together shortening cell

Question 9

Flexion:

Answer 9

Decreases angles between bones at joint

Question 10

Extension:

Answer 10

Increases angle between bones at joint and returnes bones to original location after flexion

Question 11

Hyperextension:

Answer 11

Angle between bones at joint increases beyond normal position

Question 12

Adduction:

Answer 12

Movement toward midline

Question 13

Abduction:

Answer 13

Movement away from midline

Question 14

Circumduction:

Answer 14

Movement of distal end of limb in a circle

Question 15

Rotation:

Answer 15

Revolution on bone’s longitudinal axis

Question 16

Elevation

Answer 16

Superior motion of body part

Question 17

Depression:

Answer 17

Inferior motion of body part

Question 18

Protraction:

Answer 18

Anterior motion of body part in transverse plane

Question 19

Retraction:

Answer 19

Posterior motion of body part in transverse plane

Question 20

Inversion:

Answer 20

Movement of sole of foot medially

Question 21

Eversion:

Answer 21

Movement of sole of foot laterally

Question 22

Dorsiflection:

Answer 22

Bending of foot at ankle superiorly

Question 23

Plantar flexion:

Answer 23

Bending of foot at ankle inferiorily

Question 24

Supination:

Answer 24

Rotation of palm of hand anteriorly

Question 25

Pronation:

Answer 25

Rotation of palm of hand posteriorly

Question 26

Opposition:

Answer 26

Movement of thumb to touch fingers on same hand

Question 27

What are the major muscle groups?

Answer 27

Muscles of femoral region, quadriceps group, hamstrings group, gluteal group, crural region, abdominal muscles, cervical muscles, thoracic muscles, muscles of shoulder and arm, muscles of head

Question 28

What are the muscles of femoral region and what do they do?

Answer 28

Sartorius: Flexes and abducts leg at hip joint
-superficial thigh muscle that runs from outer hip to inner knee
Tensor fasciae late: Flexes and abducts leg at hip joint
-lateral upper thigh and hip area- muscle pulls on the white fascia latae which covers the vastus lateralis muscle on the lateral part of the thigh
Gracilis: adducts leg at hip joint
-superficial medial thigh muscle runs from groin area to inner knee
Adductors: Adducts leg at hip joint
-several muscles found deep to the gracilis, in the groin area

Question 29

What are the muscles of the quadricep group and what do they do?

Answer 29

Rectus Femoris: Flexes leg at the hip joint, extends leg at the knee
-straight cylinder of muscle just under the sartorius and sandwiched between the vastus medialis and vastus lateralis
Vastus lateralis: Extends leg at the knee
-lateral to the rectus femoris and partially hidden by the fascia latae
Vastus medialis: extends leg at the knee
-medial anterior thigh muscle runs anterior and parallel to the femoral artery and vein
Vastus intermedius: extends leg at the knee
-deep femoral muscle that lies below the rectus femoris

Question 30

What are the muscles of the hamstrings group and what do they do?

Answer 30

Biceps femoris: extends leg at hip joint, flexes leg at knee
-superficial muscle on posterior thigh
Semimembranosus: flexes leg at knee
-deep muscle on posterior thigh
semitendinosus: flexes leg at knee
- superficial to semimembranosus on posterior thigh

Question 31

What are the muscles of the gluteal group and what do they do?

Answer 31

Gluteus maximus: extends leg at hip joint
-larger superficial muscle found in the posterior region of the hip
Gluteus medius: abducts leg at hip joint
-smaller superior muscle found in the posterior region of the hip covered by a strong layer of fascia
Gluteus minimus: abducts leg at hip joint
-smaller superior muscle found in the posterior region of the hip covered by a strong layer of fascia

Question 32

What are the muscles of the crural region and what do they do?

Answer 32

Gastrocnemius: plantar flexion of foot
- the calf muscle with the two big bellies on the posterior side of the leg
Soleus: plantar flexion of foot
-inferior to most of the gastrocnemius
Tibialis anterior: dorsiflexion of foot
-anterior foreleg muscle parallel to the tibia (shin bone) - the bone is the medial edge of the muscle

Question 33

What are the muscles of the abdomen and what do they do?

Answer 33

Rectus abdominus: flexes and rotates trunk
-the most anterior abdominal muscle with muscle fibers running from chest to groin on both sides of the linea alba (white line of connective tissue in the midline of the abdomen)
external oblique: flexes trunk, compresses abdomen, lateral flexion and trunk rotation
-most superficial of this three layer area on the side of the abdomen-fibers run on an angle from the ribs down towards the midline
Internal oblique: flexes trunk column, compresses abdomen, lateral flexion and trunk rotation
-the middle layer of this three layer area on the sides of the abdomen -fibers run on an angle from the lateral groin up towards the midline. It is deep to the eternal oblique
Transverse abdominus: compresses abdomen
-deep to the internal oblique-fibers run horizontally (in a transverse plane)

Question 34

What are the muscles of the cervical and what do they do?

Answer 34

Sternocleidomastoid: rotates and flexes head
-muscles that form a V in the neck from the sternum and clavicles to the mastoid process
Sternohyoid: depression of the hyoid bone
-throat muscle that runs from the hyoid bone to the sternum

Question 35

What are the thoracic muscles and what do they do?

Answer 35

Pectoralis major: adducts arm at shoulder
-the larger and more superficial muscle
Pectoralis minor: adducts arm at shoulder
-the smaller pectoral muscle, is deep the pectoralis major and attaches to rib bones
Latissimus dorsi: adducts arm at shoulder
-large muscle that runs from the backbone to the axilla
Serratus anterior: rotates scapula upward and laterally
- deep to the pectoral muscles and latissimus dorsi is a fan shaped “serrated” muscle that radiates out of the armpit towards the “ventral” side

Question 36

What are the muscles of the shoulder and arm and what do they do?

Answer 36

Trapezius: rotates,extends head; scapula protraction
-superficial muscles of the back that are on both sides of the backbone from the lumber region to the neck
Deltoid: flexes extends, and abducts arm at shoulder
-shoulder muscle that starts at the acromion (bony point on the shoulder) where the trapezius ends and runs out to the upper humorous (upper arm bone)
Biceps brachii: flexes arm at elbow
-anterior upper arm muscle - pull insertion of the pectorals up to see the cylindrical muscle on the humerus
Brachialis: flexes arm at elbow
-lateral upper arm muscle -between the biceps brachii and triceps brachii
triceps brachii: extends arm at elbow:
-posterior lower arm muscle - large group posterior and inferior to the humerus
Flexors: flex wrist and fingers
-located in the anterior compartment of the forearm
Extensors: extend wrist and fingers
- found in the posterior compartment of the forearm

Question 37

What are the muscles of the head and what do they do?

Answer 37

Masseter: elevates mandible
-large muscle that has its origin on the zygomatic arch and inserts on the mandible. It can be found in close association with the large parotid salivary gland