*Winter Review Week
*Homework
*Set up for “Memory” *Create flashcards for:* Perimysium* Synergist*Aerobic* Leukocytes* Plasma* Eccentric contraction* Leukemia*Motor Unit* Smooth Muscle* Tendon
*Types of Muscle
• Attaches to bone/face skin• Long, cylindrical, striated• Voluntary
Skeletal
• Walls of the heart• Involuntary• Rhythmic contraction
Cardiac
• Walls of hollow organs• Involuntary, hormones/nervous
system• Slow contraction
Smooth
*Function
1. Producing Movement2. Maintain posture and position3. Stabilize joints4. Generate heat
*Type I v. Type II
*Type I – Slow twitch*Type II – Fast twitch*Type II(a)*Type II(b)
*Type I
*Oxygen efficient*Necessary for extended muscle contraction (over
time)*Longer time before fatige
*Type II
*Anaerobic*Speed and strength*Fatigue quickly*Type II(a)*Combination of type I and type II
*Type II(b)*Classic fast twitch*Rapid firing
*Think Critically
*In what areas of the body are you likely to NOT find type 1 fibers, only type II fibers?
*Muscle Tissue Anatomy
*What are the 6 parts of that make up muscle tissue?*Muscle Fiber*Endomysium*Fascicle*Perimysium*Epimysium*Tendon
*Structure of Muscle
*Actin/Myosin
*At a much smaller level, myofibrils are made up of smaller myofilaments*Myofilaments composed of 2 different types of
contractile proteins, Actin and Myosin*Slide past each other to create a shortening
(contraction)
*Neuromuscular Junction
*Neuron
*Neuromuscular Junction
*All muscle must be stimulated*In between axon and muscle is a neuromuscular
junction*Motor axon breaks into several branches called
axon terminals*Each branch forms a neuromuscular junction
with a single muscle cell*1 neuron stimulates many muscle fibers
*Motor unit – neuron and all the muscles it stimulates
*Neuromuscular Junction
*Neuron and muscle fibers DO NOT touch*Separated by small, fluid filled gap called the
synaptic cleft*Acetylcholine (neurontransmitter) carries the
impulse across the gap and delivers the message*If enough acetylcholine is released, the
permeability of the receiver changes, allowing for sodium to enter the surface*Results in possible muscle contraction
*Types of Muscle Contraction
*Types of Muscle Contraction
*Types of Muscle Contraction
*What are the 3 types of muscle contraction? Explain each one*Isometric*Concentric*Eccentric
*REVIEW
*Direct Phosphorylation*Phosphorylation of ADP by creatine phosphate (CP)*Creatine Phosphate found in muscles
*As ATP depletes, CP and ADP react to create ATP and Creatine*Muscles store about 5x as much CP as ATP*CP stores are quickly depleated as well (15 seconds)
*Review
*Aerobic Respiration*At rest, during light or moderate exercise, the majority of ATP
used for muscle contraction comes from Aerobic Respiration*95%
*Occurs in mitochondria of the cell*Glucose is broken down to CO2 and water*Energy released from broken bonds are captured in ATP
molecules*What happens to the CO2?
*32 ATP per 1 glucose*Slow and requires continuous oxygen and fuel
*Review
*Anaerobic glycolysis*Does not require oxygen
*Occurs in cytosol*Glucose broken down to pyruvic acid and small
amounts of energy are captured in ATP bonds*2 ATP per 1 glucose
*If enough oxygen is present, pyruvic acid enters mitochondria and follows aerobic pathway
*When exercise becomes intense, pyruvic acid turns to lactic acid and process is referred to as anaerobic glycolysis
*Muscle Fatigue and Oxygen
Deficit
*Muscle fatigue – when muscles are exercised strenuously for a long time*Unable to contract even though it is being stimulated
*Contractions will weaken until they are no longer possible*Muscle fatigue due to oxygen deficit*Not able to keep up with oxygen demand
*Muscles lack oxygen, lactic acid accumulates
*Worksheet!
*Use the worksheet to sequence the steps of a muscle contraction*Bring to class on Monday
*Homework
*Set up for “Memory” *Create flashcards for:* Perimysium* Synergist*Aerobic* Leukocytes* Plasma* Eccentric contraction* Leukemia*Motor Unit* Smooth Muscle* Tendon