Muscular System

Question 1

Explain the Steps Involved in the Muscle Contraction (in relation to actin, myosin, role of calcium, troponin and tropomyosin)

Answer 1

• Calcium ions bind to troponin.
• Tropomyosin shifts, exposing binding sites on actin
• Myosin head attach to actin, forming cross bridges
• Power stroke occurs, sliding act in filaments over myosin.
• ATP binds to myosin, causing it to release actin.
• Calcium is actively transported back into the sarcoplasmic reticulum.

Question 2

State One Site for Administering Intramuscular Injection

Answer 2

Deltoid

Question 3

Explain why Nurses Aspirate
Before Administering Intramuscular Medication

Answer 3

To ensure the needle administered isn’t in a blood vessel, preventing accidental intravenous injection