1. Musculoskeletal System
Quiz 2
Homework
Attendance

2. Smooth Muscle used for involuntary actions
Innervated by the autonomic nervous system
Found in the digestive tract, bladder, uterus, blood vessel walls, and other places.
Has actin and myosin filaments
No striations=no sarcomeres

3. Smooth Muscle Contractions
Same as skeletal muscle
Use actin and myosin
Regulated by calcium ions
Different from skeletal muscle
Contractions are slower
Contractions can occur for a longer amount of time
Have both inhibitory and excitatory synapses
Has myogenic activity: can contract without stimulation from the nervous system

4. Cardiac Muscle
The muscle tissue of the heart has cardiac muscle fibers.
Has actin and myosin filaments.
Has striations, so has sarcomeres.
One or two central nuclei
Innervated by the autonomic nervous system, which regulates heart beat.
Myogenic

5. Energy Reserves
Can break down fatty acids, glycogen, and glucose to produce ATP
Also, energy can be temporarily stored as Creatine Phosphate
Exercise
At Rest

6. Myoglobin a protein similar to hemoglobin structure
unique to muscle tissue
has high O2 affinity
binds to O2 from blood and holds onto it.

7. Questions Fill in this chart: Smooth Cardiac Involuntary/Voluntary
Innervated by
Found in
Actin and Myosin Filaments
Striations
Sarcomeres
Myogenic

8. Questions Part 6-1

9. Strenuous Exercise During exercise:
Muscle cells very quickly run out of oxygen
Myoglobin gives oxygen to muscle
Sometimes, extra oxygen from myoglobin is not enough.
Muscle gets oxygen from anaerobic respiration.
Result: lactic acid build up

10. Connective Tissue binds and supports other tissue.
2 kinds: loose connective tissue and dense connective tissue

11. Loose Connective Tissue
Found throughout the body
Binds epithelium to other tissues
Holds organs in place

12. Loose Connective Tissue
Has three protein fibers:
collagenous fibers:
Has collagen and very strong
elastic fibers:
Has elastin and gives strength to connective tissue.
Reticular fibers:
branched, tightly woven fibers that join connective tissue to adjoining tissue.

13. Loose Connective Tissue
2 cells:
fibroblasts
Secrete substances that make extracellular fibers
macrophages
Eat bacteria and dead cells using phagocytosis

14. Dense Connective Tissue
Has very high amount of collagenous fibers
Regular dense connective tissue is very strong
Dense connective tissue forms tendons (joins muscle to bone) and ligaments (hold bones together at joints)

15. Muscle-Bone Interactions
Movement depends on interaction between skeletal and muscular system
If a muscle is attached to 2 bones, only 1 bone moves.
origin:
End of the muscle attached to stationary bone.
Proximal end in limb muscles
insertion
End of the muscle attached to the bone that moves during contraction
Distal end in limb muscles

16. Muscles work in Antagonistic Pairs

17. Synergistic Muscles
Help principal muscles during movement.

18. Flexor/Extensor Muscles
Contracts to decrease the angle of a joint
extensor
Contracts to straighten the joint

19. Abductor/Adductor Muscles
moves a part of the body away from the body's midline
adductor
moves a part of the body toward the midline

20. Questions Part 6-2