*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