Muscle contraction - sliding filament theory

The gap between a neuron and a muscle cell: (#4 in the diagram)

• synaptic cleft or synapse

• sarcolemma
• vesicle
• Ca²⁺ ion

Region where a motor neuron comes in close contact with a muscle cell.

• neurotransmitter
• muscular dystrophy
• muscle tension
• neuromuscular junction

The neurotransmitter stored in the axon terminal identified as #3

• Acetylcholine
• Protein Channel
• Calcium Ion (Ca²⁺)
• Syanptic Cleft

The organelle containing actin and myosin identified as #9

• ACh
• Sarcolemma
• Vesicle
• Myofibril

The functional unit of a muscle that contracts is ...

• sarcomere

• motor unit

• fascicle

• myofibril

Thick filaments are in a myofibril are

• ATPase
• Sarcoplasmic reticulum
• Actin
• Myosin

Thin filaments in a myofibril are

• Sarcomeres
• Sarcoplasm
• Actin
• Myosin

What two chemicals are necessary for muscle contraction to occur?

• Niacin and Potassium
• Calcium and ATP
• Sodium and Potassium
• Ach and Potassium

What is the structure that stores the Calcium in the muscle cell.  

• Sarcoplasm
• Sarcolemma
• Sarcoplasmic Reticulum
• Myoglobin

Skeletal Muscle contraction is initiated when the ________ sends a message to the muscle cell.  

• Muscle cell
• Neuron
• Gland
• None of the above