1. Muscles Pre-test/Packet Muscles to Know Coloring
Monday - 9/26/16
Question of the Day
Agenda
What are 3 every day functions that your muscular system allows you to do?
Return tests
Muscles Pre-test/Packet
Muscles to Know Coloring
Muscle Notes

2. Tuesday 9/27/16
Question of the Day
Agenda
Name the tissues that…
Are involuntary?
Are striated?
Have intercalated disks?
Are voluntary?
Are attached to bone?
Are in the heart?
Are not striated?
Moves substances along a pathway?
1. Review
2. Microscopic Anatomy of Skeletal Muscle Notes
3. DIY Skeletal Muscle

3. Thursday - 9/29/16 Thin myofilaments are made of the protein _____.
Question of the Day
Agenda
Thin myofilaments are made of the protein _____.
Thick myofilaments are made of the protein _____.
1. Review
2. Notes
3. Work on packet
4. Lab

4. Friday - 9/30/16 1. Review 2. Finish notes 3. Work on packet
Question of the Day
Agenda
Place these structures of the skeletal muscle in order from largest to smallest
1. fascicle
2. myofilament
3. muscle fiber
4. myofibril
5. sarcomere
1. Review
2. Finish notes
3. Work on packet

5. Monday - 10/3/16
Question of the Day
Agenda
Put the steps of the sliding filament theory in the correct order.
1. Another cross bridge is formed
2. Actin cross bridges to myosin
3. Another power stroke slides actin closer to the center of the sarcomere
4. Cross bridge is broken
5. Actin slides past myosin in a short power stroke
1. Review
2. Muscular System Project - due at the beginning of class on Thursday
Test is Thursday!

6. The Muscular System

7. Comes from the Latin word mus meaning “little mouse”
What are “muscles?”
Comes from the Latin word mus meaning “little mouse”

8. Types of muscular tissue
What are the 3 types of muscular tissue?
(Think back to when we covered histology.)

9. Types of muscular tissue
1. Skeletal Muscle Tissue
2. Cardiac Muscle Tissue
3. Smooth Muscle Tissue

10. Types of muscular tissue
Skeletal Muscle Tissue –
Found attached to bone
Striated, multinucleated
Voluntary (often reg. by
reflexes)
Exerts great force but
tires easily

11. Types of muscular tissue
Cardiac Muscle Tissue –
Found only in the heart
(bulk of heart walls)
Has striations and
intercalated disks
Involuntary

12. Types of muscular tissue
Smooth Muscle Tissue –
Found in the walls of
hollow internal structures
No striations
Involuntary
Propels substances along a
definite pathway

13. Functions of muscular system
Movement
Maintains posture
Regulate organ volume
Move substances within the body
Produce heat
Stabilize joints

14. What does skeletal muscle tissue look like?

15. Microscopic Anatomy of Skeletal Muscle
Epimysium
Surrounds the entire muscle
Continuous with tendons (attaches the muscle to the bone)

16. Microscopic Anatomy of Skeletal Muscle
Perimysium
Surrounds a bundle of muscle fibers (called fascicles)

17. Microscopic Anatomy of Skeletal Muscle
Endomysium
Surrounds each muscle fiber (muscle cell)

18. What does skeletal muscle look like?
Khan Academy Video

19. Design your own muscle fiber
DIY muscle fiber

20. 1. 2. 3. 4. 5.

22. Microscopic Anatomy of Skeletal Muscle
Myofibrils are composed of alternating light (I) and dark (A) bands (called myofilaments) – gives the muscle its striped appearance

23. What does skeletal muscle look like?
Myofibrils
(light and dark
bands) are
divided into
compartments
known as
sarcomeres.

24. What does skeletal muscle look like?
Each sarcomere is divided into sections.
A band
I band
H zone
Z disc

25. What does skeletal muscle look like?

26. What does skeletal muscle look like?
Sarcomeres are arranged into even smaller structures called myofilaments.
Myofilaments produce banding pattern by 2 proteins
Myosin (thick)
Actin (thin)

27. What does skeletal muscle look like?
Thick myofilaments are
composed of the protein
myosin.
Split ATP to generate the
power needed for
muscle contraction

28. What does skeletal muscle look like?
Thin filaments are
composed of the
protein actin.
Slide toward each
other during
contraction

29. Sarcomere coloring

30. Physiology of skeletal muscle contraction
Skeletal muscle requires stimulation from the nervous system in order to contract.
Motor neurons are the cells that cause muscle fibers to contract.

31. Neuromuscular junction
Junction between muscle cells

32. Overview of events at the NMJ
Action potential travels down the axon of the motor neuron to the end bulbs (axon terminals)
Acetylcholine (Ach) is released into the synaptic cleft (gap)

33. Overview of events at the NMJ
Ach binds to Ach receptors on the motor end plate
The binding of Ach to its receptors causes a new action potential to be generated along the muscle cell membrane

34. Overview of events at NMJ
Immediately after it binds to its receptors, Ach will be broken down
Prevents continuous contraction of the muscle cell
Events at the NMJ

35. Blocks the release of Ach by the neuron Weakens muscle ~3-4 months
Botox
Botulinum toxin
Blocks the release of Ach by the neuron
Weakens muscle ~3-4 months

36. Physiology of skeletal muscle contraction
Myofilament contraction animation

37. Providing energy for muscle contraction
As muscles contract, ATP is broken down to release the needed energy and break cross bridges
In order for muscle contraction to continue, ATP must be regenerated (creatine phosphate, anaerobic respiration and aerobic respiration)

38. No oxygen = No ATP production Myosin/Actin cross bridges do not break
Rigor Mortis
No oxygen = No ATP production
Myosin/Actin cross bridges do not break

39. Creatine Phosphate
At rest, muscle fibers make more ATP than is needed which is then used to make creatine phosphate + ADP
When muscle begins to contract, phosphate group is transferred back to ADP forming ATP
Enough energy for short bursts (15 sec)

40. Anaerobic Respiration
Glucose broken down into pyruvic acid which is then converted to lactic acid (when oxygen levels are low) = 2 ATP
~ 30 to 40 seconds of maximal muscle activity

41. Aerobic Respiration
In the presence of oxygen, pyruvic acid enters mitochondria where it generates ATP
36 ATP molecules from 1 glucose molecule
Lasts more than 10 minutes

42. Muscle/Body Movements
Flexion: decreases the angle of the joint and brings two bones closer together

43. Muscle/Body Movements
Extension:
increases the angle between 2 bones or parts of the body
Opposite of flexion

44. Muscle/Body Movements
Abduction:
moving a limb away from the midline
Adduction:
movement of limb toward the body midline

45. Bell Work - 11/18/14
Put the steps of the sliding filament theory of muscle contraction in the correct order.
1. Another cross bridge is formed
2. Actin cross bridges to myosin
3. Another power stroke slides actin closer to the center of the sarcomere
4. Cross bridge is broken
5. Actin slides past myosin in a short power stroke

46. What causes cramps? Inadequate blood supply Mineral depletion
Myosin fibers cannot break free
of actin

47. Nutritional Imbalance
Why is my eye twitching?
Eye strain
Tiredness
Too much caffeine
Allergies
Nutritional Imbalance

48. FOP video
Dancing Zombie Squid video
Pat Grange: ALS video