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BaseballBaseballThe Muscular SystemThe Muscular System

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• What role does ATP play in muscle contraction?– Answer: it

is the source of energy for the sliding filaments

• Which muscle allows you to wrinkle your forehead?– Answer:

frontalis

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• What structures connect muscles to bone?– Answer:

tendons

• Where is smooth muscle located? Cardiac?– Answer:

1)smooth: hallow organs (stomach, intestine, etc) 2)cardiac:heart

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• Define origin & insertion points.– Answer: 1) points

where muscle attaches to bone

2) origin :immovable or less movable point of attachment (muscle to bone) 3)insertion: movable point of attachment

• What is the minimal strength needed for muscle contraction?– Answer:

threshold

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• What is a recording of an electrically stimulated isolated muscle called?– Answer:

myogram

• Why does skeletal muscle look striated?– Answer:

alternating layers of light and dark bands (actin & myosin)

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• Which diagram shows a relaxed sarcomere, 8,9 or 10? Explain why– Answer:

10…..z lines are far apart, long sarcomere

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• During what time interval would the latent period occur?– Answer: 0-

2.5 msec

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• Identify area 6 & indicate the role it plays in muscle contraction.– Answer:

Mitochondrion… supplies ATPs

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• What type of summation is indicated by the myogram?– Answer:

tetanic contraction

• What is it called when muscles decrease in size or seem to waste away.– Answer:

atrophy

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• Identify the fleshy muscle that runs across the cheek…whistling & chewing muscle– Answer:

Buccinator

• Increasing the angle between to bones is best known as flexion, true or false?– Answer:

false….extension

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• Identify the area labeled # 5 & 6– Answer:

biceps brachii & external obliques

• Gluteus maximus was named how (2 reasons)– Answer:

gluteal (body region) & size (maximus=large)

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• Identify the area labeled # 5 & 6– Answer:

5)deltoid & 6)trapezius

• What is oxygen debt?– Answer:

the amount of oxygen required to convert built up lactic acid into glucose

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• Identify the area labeled # 1 & 4– Answer:

1)gluteus medius & 4) gastrocnemius

• Why do actin and myosin come in contact with eachother only some of the time?– Answer:

Binding site on actin is covered up…preventing contact

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• Identify area 7 & what is found within it?– Answer:

synaptic vesicles contains neurontransmitters (like acetylcholine)

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• Identify the area labeled # 10– Answer:

bucinnator

• Which muscle helps you wink? (name and number it)– Answer:

orbicularis oculi #2

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• When a muscle can no longer contract it is said to be….– Answer:

fatigued

• Identify the area labeled # 1 and indicate its function– Answer:

sternocleidomastoid allows you to bow your head

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• Identify the area labeled # 8 & indicate the action on #5– Answer:

sartorius & dorsiflexion of the foot (tibialis anterior)

• Identify the area labeled # 2 to which group of muscles does this belong ? – Answer:

Vastus medialis…. quadriceps

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• If a muscle fiber contracts at all, it will contract completely…. This is also known as– Answer:

all or none theory

• Identify by name & number the muscles that comprise the hamstrings– Answer:

9-biceps femoris 8-semitendinosus 7-semimembranosus

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• Identify the area labeled

# 5– Answer:

zygomaticus

• Which muscle helps you kiss? (name and number it)– Answer:

orbicularis oris #6

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• Identify the area labeled # 4 & 6– Answer:

latissimus dorsi & triceps brachii

• When several muscles contract at a time, the one muscle responsible for the majority of movement is called– Answer:

the prime mover

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• Identify the area labeled # 1, 2 &3– Answer:

1:A (dark) band 2: I (light) band 3: H zone

• What kind of muscle opposes or reverses a movement?– Answer:

antagonists

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• Identify Area #3 – Answer:

Z Line

• What substance is #4 & 6?– Answer:

Actin & Myosin

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• Identify the area labeled # 4 & 6– Answer:

soleus & peroneus

• One neuron and all the skeletal muscle cells it stimulates is called a– Answer:

motor unit

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• Order the events from first to last A. Acetylcholine is released from axonal terminal into synaptic cleft.B. Sarcomeres contractsc. Depolarization triggers action potential, travels along sarcolemma & T tubules.

D. motor end plate is depolarizedE. Action potential arrives at axonal terminal

– Answer: E-->A-->D-->C--->B

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• Even when a muscle is at rest, its fibers usually remain partially contracted this is called….– Answer:

muscle tone

• An increase in the number of motor units being activated is called– Answer:

recruitment