Sliding FIlament Theory

Contractile unit of a muscle.

• 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

Calcium:

• causes ATP binding to actin

• increases the action potential along the sarcolemma

• binds to proteins on myosin

• triggers the binding of myosin to actin

What is a crossbridge?

• Where myosin binds to actin

• Where the calcium crosses into the cytoplasm

• Where calcium binds with troponin

• None of the answers are correct.

The energy needed to perform a muscle contraction comes directly from

• ATP

• Oxygen

• Glucose

• Calcium

Tags

NGSS.HS-LS1-7

The neurotransmitter stored in the axon terminal identified as #3

• Calcium Ion (Ca²⁺)

• Protein Channel

• Acetylcholine

• Synaptic Cleft

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

• Sarcoplasm

• Sarcolemma

• Myoglobin

• Sarcoplasmic Reticulum

Which filament slides inward during muscle contraction

• Actin

• Myosin

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

• synaptic cleft
• sarcolemma
• vesicle
• Ca²⁺ ion