Get out a sheet of paper and
something to write with.
Monday, November 16, 2015
On your paper
•Think back to your homework
(sliding filament videos)
•What did you learn about the
sliding filament theory?
Reminders
•Extra Credit due Wed.
•next Monday = 1, 3, 5 block;
Tuesday = 2, 4, 6
LEQ
• Microscopically, how is muscle tissue organized?
• What are the roles of actin and myosin in muscle
contraction?
• What are the steps of the sliding filament theory?
• How do muscle cells obtain the necessary energy for
movement?
• How does a signal pass across the neuromuscular
junction?
Muscle Notes (continue on same paper)
Basics
• Functions of muscles: movement,
maintain posture, source of body heat
• There are over 600 muscles in the body
• Muscles use chemical energy to
contract (shorten)
Structure
• Each muscle is an organ
• Muscles are made up of skeletal muscle tissue,
connective tissues, nervous tissue & blood
• Fascia covers each muscle; this is connected to
the tendons, that are fused to bone
• Fascicles: bundle of muscle fibers (cells)

Sarcolemma: cell membrane
Structure
•Myofibrils: bundle of filaments
•Sarcomere: contraction unit of a
myofibril; made of actin and myosin
•Thin filaments: made of actin
•Thick filaments: made of myosin
A skeletal muscle is composed of a variety of tissues
Slide number: 1
Muscle
Bone
Fascicles
Tendon
Muscle fibers (cells)
Fascia
(covering muscle)
Myofibrils
Epimysium
Perimysium
Thick and thin filaments
Endomysium
Fascicle
Axon of motor neuron
Blood vessel
Myofibril
Nucleus
Sarcoplasmic
reticulum
Muscle fiber
Sarcolemma
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Filaments
Neuromuscular Junction
• a.k.a myoneural junction
• The site where the motor neuron and muscle
fiber meet
• Motor end plate on muscle fiber; sarcolemma is
tightly folded; lots of nuclei and mitochondria
• Cytoplasm of motor neuron has lots of
mitochondria and synaptic vesicles that store
neurotransmitters
What happens at neuromuscular junction
1. Nerve impulse travels from the brain or spinal cord
2. Impulse reaches end of motor neuron axon and causes
synaptic vesicles to release neurotransmitter
(acetylcholine) into the gap between the neuron and
motor end plate of the muscle fiber
3. Muscle fiber contracts
• One neuron may control many muscle fibers
• An impulse will cause each muscle fiber to contract at
the same time
Energy Notes p. 195
• Divide a sheet of paper into 3rds
• Label each column
• Phosphorylation of ADP
• Aerobic Respiration
• Anaerobic Respiration / lactic acid formation
• In each column write a description IN YOUR OWN WORDS (you should be able to understand
what you wrote)
Read pgs. 189-196
• Take notes on the following:
• Nerve stimulus & action potential
• How a signal passes across the neuromuscular
junction
• The steps of the sliding filament theory
• Have notes done & ready to go for tomorrow