Name _____________Key___________________________date ____________hour ___________
Chapter 9: Muscles and Muscle Tissues
1.
A person has just gotten a cast removed from their arm notices that the arm that was in the cast
is _smaller than the other. This is a result of muscle _________atrophy______________.
2. An increase in muscle size results from an increase in the number of ______myofibrils_______
in the muscle __________fiber___________.
3. Anaerobic respiration makes __2_____ATP.
4. Aerobic respiration makes __34_____ATP
5. When the muscle can no longer contract even when it is stimulated or when the muscle in not able
to fully contract, this is called ___________muscle fatique___________.
6. Muscle hypertrophy is: increase in the diameter of the muscle fiber as it increases with
myofilaments.
7. Skeletal muscles directly move the body by: pulling on the bones of the skeleton
8. Skeletal muscles do/don’t generate heat as they contract. do
9. The bundle of collagen fibers at the end of a skeletal muscle that attaches the muscle to bone is
called a(n): tendon
10. The three types of muscle tissues are: a. _________skeletal____________________
b._____cardiac____________________
c. ________smooth__________________
11. When does rigor mortis begin after death and how long will it last? 3-4 hours after death/ will
last 48-60 hours
12. What is the cause of rigor mortis (explain more than just death)? The Calcium in the SR leaks
out and causes the myosin to attach to actin and cause contraction. Since breathing stops,
no new ATP is getting made so the cross-bridge stays attached.
13. After strenuous exercise, soreness of muscles is most likely the result of ______lactic acid
build up_______.
14. When intracellular calcium levels are high, the muscle is in a ___contracted______________
state.
Types of muscle fibers
15. How fast a muscle fiber can contract depends on: how fast the myosin ATPase splits ATP
16. The color of muscle is determined by: the amount of myoglobin content
Write slow or fast:
17. Activities requiring aerobic endurance: slow
18. Chicken breast is made up of: slow
19. Chicken legs are made up of: fast
20. Dark meat is dominated by: slow
21. Short powerful bursts of activity: fast
22. This type of muscle fiber appears red and is the smallest of the fiber types: slow
23. This type of muscle fiber has very fast-acting myosin ATPases and depends upon anaerobic
metabolism during contraction: fast
24. This type of muscle fiber is abundant in the muscles responsible for posture: slow
25. White meat is dominated by: fast
Microscopic Anatomy
26. A sarcomere is the distance between two Z lines.
27. An elaborate network of membranes in skeletal muscle cells that function in calcium storage is
the: Sarcoplasmic Reticulum
28. Both actin and myosin are found in the ________A band________________________
29. Myofibrils account for ___80%____ of the cell volume
30. The ___I band__________ contains only actin filaments.
31. The ________A band_________ appears as dark area under the microscope.
32. The _____H zone_______contains only myosin filaments.
33. The major function of the T tubules is to:
They conduct impulses to the deepest regions of the muscle cell and to every sarcomere.
34. The muscle cell membrane is called a(n): _______sarcolemma__________________
35. The series of membranous channels that surround each myofibril is the
______Sarcoplasmic Reticulum______________
36. The smallest functional unit of a skeletal muscle fiber is the
__________sarcomere___________________
37. The striations of a skeletal muscle cell are produced, for the most part by: actin and myosin
Muscle Contraction
38. Before the cross-bridge can release, what must happen? ATP must bind to myosin
39. Calcium ions bind to the __troponin__________ molecule in skeletal muscle cells, and acts to
___remove tropomyosin from blocking actin’s active site_______.
40. During complete contraction of a muscle fiber, the ____H zone________ disappears
41. During muscle contraction, ATP binds to the __myosin______ molecule
42. During muscle contraction, the “cross-bridges” ( heads of myosin) attach to which
filaments?___actin________________
43. The sliding filament model of contraction involves. The thin filaments slide past the thick ones
so that the actin and myosin filaments overlap to a greater degree.
44. When a muscle fiber contracts, the I bands __shorten______, the H zones __disappears____,
the A bands move __closer___, to each other and their length__does NOT change_________,
and the Z lines ___reduced in distance_________
DIAGRAMS- label : fascicle, epimysium, endomysium, bone, tendon, muscle fiber, permysium,
Diagrams- Label: A band, actin, H zone, I band, M line, muscle fiber, myosin, zone of overlap,
sarcolemma, nucleus, t-tubule, sarcoplasmic reticulum, myofibril