Unit 7 -Muscular System Part 1 - Physio

Anaerobic respiration

• causes fatigue
• produces lactic acid
• produces oxygen debt
• all of these

Which of the following MUST be present for aerobic respiration? 

• carbon dioxide
• lactic acid 
• glucose
• oxygen

Acetylcholine

• is responsible for producing lactic acid
• causes an action potential to begin in muscle fibers
• gives us good muscle tone
• causes cramps and spasms

Which chemicals must be present for muscles to contract?

• calcium
• ATP
• lactic acid
• ATP and Calcuim

The part of a skeletal muscle from z-line to z-line is called

• nucleus
• H-zone
• perimysium
• sarcomere

Which structure contains large amounts of calcium used for muscle? 

• sarcomere
• mitochondria
• sarcoplasmic reticulum
• myofibril

What action causes the sarcomere to shorten?

• Myosin slides over actin

• Actin slides over myosin

• Actin and myosin shorten

• Actin and myosin move closer together

Which of these produces exactly 2 ATP molecules?

• Aerobic respiration

• Direct phosphorylation

• Anaerobic respiration

• Creatine phosphate

What happens with myosin attaches to actin?

• Myosin heads pull towards the ends of the sarcomere

• Calcium ions begin to detach

• Calcium ions bind to myosin

• Myosin heads pull towards the center of the sarcomere

What action causes the sarcomere to shorten?

• Myosin slides over actin

• Actin slides over myosin

• Actin and myosin shorten

• Actin and myosin move closer together