Anatomy Digestive/Muscle

Certainly! Here is the study guide with the questions and answers filled in.

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1. One muscle cell = muscle fiber. A number of fibers together are called a:

Fascicle

2. A number of fascicles are bound together to form a:

Muscle

3. An individual muscle fiber can be broken down into:

Myofibrils, which can be further broken down into:

Sarcomeres, which can in turn be broken down into myofilaments.

4. Myofilaments are striped in appearance due to the two proteins that they are made of. They are:

Actin (thin) and myosin (thick)

5. The zagged line that runs down the actin chains is called the:

Z-line

6. Muscles can only:

Contract or relax

7. Name the four functions of muscles:

Movement, stability, heat production, and control of body openings

8. Which of the following is attached to the more movable bone?

Insertion

9. Circle the appropriate characteristic for each muscle type and list where you would find the type of muscle:

- a. **Skeletal:** Striated, tires easily, voluntary; found attached to bones.

- b. **Cardiac:** Striated, tireless, involuntary; found in the heart.

- c. **Smooth:** Non-striated, tireless, involuntary; found in walls of hollow organs.

10. Tendons connect bone to:

Muscles

11. One neuron and all of the skeletal muscle cells it stimulates is called a:

Motor unit

12. What is the spot where a nerve inserts into the muscle called?

Neuromuscular junction

13. At this junction, the neurotransmitter that is released is called:

Acetylcholine (ACh)

14. The electrical pulse that flows through a muscle is called the:

Action potential

15. The ions that are most important in muscle contraction are:

Calcium and sodium ions

16. When a muscle is unable to contract even though being stimulated, it is called:

Muscle fatigue

17. The type of contraction that occurs when muscle filaments are successful in their sliding movements, and the muscle shortens:

Isotonic contraction

18. The type of contraction that occurs when muscles don’t shorten, “skid on ice”:

Isometric contraction

19. The body is continuously partially contracting. This creates:

Muscle tone

20. When the body is under continuous contraction, the disorder is called:

Muscle spasticity

21. Any exercise regime should contain which types of activities or exercises:

Aerobic, anaerobic, and flexibility activities

22. Jogging, biking, swimming, etc., are examples of:

Aerobic exercises or endurance exercises

23. The orbicularis oris is an example of what type of muscle?

Circular muscle

24. What is a muscle that feathers called?

Pennate muscle

25. Muscles always work in:

Pairs

26. The muscle in the pair with the major responsibility is called the:

Agonist (prime mover); The opposite muscle is called the:

Antagonist

27. Joint actions are termed:

- Decrease the angle of a joint = Flexion

- Increase the angle of a joint = Extension

- Moving away from the midline = Abduction

- Towards the midline = Adduction

- Bringing the foot up to the shin = Dorsiflexion

- Tip toes, or toes pointed down = Plantar flexion

- Around longitudinal axis = Rotation

- Soles of feet face medially = Inversion

- Soles of feet face laterally = Eversion

28. The first movements of the fetus that the mother can feel are called:

Quickening

29. As you age, the size and strength of muscle cells:

Decrease

30. The withering away of muscles is called:

Atrophy

31. Muscles cells can become stiff due to:

Lactic acid build-up

32. Steroids are a derivative of:

Testosterone or cholesterol

33. A genetic disease characterized by muscle tears that will not heal is called:

Muscular dystrophy

34. When actin and myosin don’t “let go” when they slide together at their bonding site it is called:

Rigor mortis (lasts only about 24 hours, then decay softens the body).

35. When a muscle is overstretched, it becomes swollen due to bleeding and is called a:

Strained muscle; A worse version is called a:

Torn muscle

36. Shin splints are either the result of a:

Stress fracture or tendonitis

37. A spasm in a muscle is called a:

Cramp

38. Sustained contractions of the muscles in the head and neck area may lead to:

Tension headaches

39. Which type of sprain or strain is the worst?

3rd-degree sprain or strain

40. Name some of the criteria that may determine how a muscle is named:

- a. Number of heads (e.g., biceps, triceps, quadriceps)

- b. Shape (e.g., deltoid, trapezius)

- c. Function (e.g., flexor, extensor, adductor)

- d. Attachment points (e.g., sternocleidomastoid, which attaches to the sternum and clavicle and inserts on the mastoid process)

41. When muscles are cold, blood vessels constrict, causing less:

Oxygen to reach the muscles.

Is fatigue faster with no blood supply?

Yes

42. Anatomy terms:

- Cephalic → Toward the head

- Proximal → Closer to the point of attachment

- Gross → Refers to large structures