Exam 3

Question 1

Sarcoplasmic reticulum:

Answer 1

Holds onto calcium ions

Question 2

Troponin:

Answer 2

Binds to tropomyosin; removes blockage of tropomyosin

Question 3

Tropomyosin:

Answer 3

Binds to actin to prevent it from binding to myosin

Question 4

ATP:

Answer 4

Allows cross bridges between actin and myosin to release

Question 5

What is pulled closer together when smooth muscle contracts?

Answer 5

Dense bodies

Question 6

Excitation-Contracting Coupling:

Answer 6

1. Action potential reaches T-tubules
2. Calcium released into sacroplasm
3. Calcium binds to troponin
4. Exposes active site of actin (thin) filament as troponin binds to tropomyosin

Question 7

What comes after Excitation-Contracting Coupling?

Answer 7

Cross-Bridge Movement

Question 8

Synostosis/Bony joint:

Answer 8

A bony joint that forms when the gap between two bones ossify (fibrous or cartilaginous joints) and become a single bone. This an immoble joint.

Question 9

Examples of a synostosis:

Answer 9

Mandible; ilium, ischium, and pubis.

Question 10

Synarthrosis/Fibrous joint:

Answer 10

Adjacent bones are bound by collagen fibers. There are 3 different kinds of fibrous joints.

Question 11

What are the 3 types of synarthrosis/fibrous joints?

Answer 11

1. Suture- Mostly immobile; found in the bones of the skull. (Serrate, lap, and plane sutures)
2. Gomphoses- Like a nail embedded in wood; tooth in its socket.
3. Syndesmoses- The collagen fibers are relatively long, so this is the most mobile kind of fibrous joint. Can be found between the shafts of the radius and ulna.

Question 12

Amphiarthrosis/Cartilaginous joint:

Answer 12

Two bones are linked by cartilage. There are 2 types.

Question 13

What are the 2 types of amphiarthrosis/cartilaginous joints?

Answer 13

1. Synchondroses- Bones are joined by hyaline cartilage. Epiphyseal plate of a growing child, and the first ribs attachment to the sternum.
2. Symphyses- Two bones are joined by fibrocartilage; can be found in pubic symphysis, and intervertebral discs.

Question 14

What is articular cartilage made up of?

Answer 14

Hyaline cartilage

Question 15

Synovial fluid:

Answer 15

Nourishes the articular cartilage, removes waste, and lubricates the joint.

Question 16

Joint (Articular) capsule:

Answer 16

Encloses the joint cavity and retains synovial fluid. It has an outer fibrous capsule and an inner synovial membrane.

Question 17

Examples of synovial joints:

Answer 17

Knee, both ends of the clavicle,

Question 18

Tendon:

Answer 18

Muscle to bone.

Question 19

Ligament:

Answer 19

Bone to bone

Question 20

Bursa:

Answer 20

A firbrous sac of synovial fluid located between adjacent muscles, where a tendon passes over bone. Helps tendons slide more easily over joints.

Question 21

Tendon (Synovial) sheaths:

Answer 21

Elongated cylindrical bursae wrapped around a tendon.

Question 22

Shoulder joint:

Answer 22

Glenohumeral joint; spherical head of the humerus articulates with the glenoid cavity of the scapula.

Question 23

Glenoid labrum:

Answer 23

A ring of fibrocartilage that deepens the joint cavity.

Question 24

What 4 muscles stabilize the shoulder joint?

Answer 24

Subscapularis, infraspinatus, supraspinatus, and teres minor. Their tendons form the rotator cuff.

Question 25

What are the 3 principal ligaments that support the shoulder joint?

Answer 25

Glenohumeral, coracohumeral, and transverse humeral ligaments.

Question 26

Elbow joint:

Answer 26

Composed of the humeroulnar (trochlea of humerus to trochlear notch of ulna) and humeroradial joint (capitulum of humerus to head of the radius).

Question 27

Side to side motions are restricted in the elbow joint by what 2 ligaments?

Answer 27

1. Radial (lateral) collateral ligament 2. Ulnar (medial) collateral ligament

Question 28

Hip joint:

Answer 28

Head of femur inserts in to acetabulum of the hip bone.

Question 29

What ligaments support the coxal (hip) joint?

Answer 29

-Iliofemoral and pubofemoral ligaments on the anterior side -Ischiofemoral on the posterior side

Question 30

Tibiofemoral (knee) joint:

Answer 30

The knee is mainly stabilized by the quadriceps tendon in front and the tendon of the semimembranous muscle in the back.

Question 31

What 2 ligaments prevent the knee from rotating when the joint is extended?

Answer 31

1. Fibular (lateral) collateral ligament 2. Tibial (medial) collateral ligament

Question 32

ACL:

Answer 32

Anterior cruciate ligament; prevent hyperextension.

Question 33

PCL:

Answer 33

Posterior cruciate ligament; prevents the femur from sliding off the from the tibia.

Question 34

Endomysium

Answer 34

Loose connective tissue that wraps around each muscle fiber.

Question 35

Perimysium:

Answer 35

Thicker connective tissue sheath; wraps around fascicles.

Question 36

Epimysium:

Answer 36

Fibrous sheath that wraps around the entire muscle.

Question 37

Fascia:

Answer 37

Separates neighboring muscles from one another.

Question 38

Excitation:

Answer 38

1. Arrival of the nerve signal and causes the release of calcium. 2. Calcium causes the release of acetylcholine. 3. Acetylcholine (ACh) binds to receptors in sacrolemma. 4. Ligand-gated ion channels (Na come in, K comes out) create an end-plate potential. 5. Voltage-regulated ion gates create action potential.

Question 39

Unhappy triad:

Answer 39

ACL, Medial meniscus, and tibial collateral ligament