Sliding Filament Model of Muscle Contraction

Front

Calcium binds to ___ of the troponin-tropomyosin complex.

Back

troponin

Front

Contractile unit of a muscle.

Back

sarcomere

Front

Dark bands are also called ___ bands.

Back

A

Front

___ forms a crossbridge with actin.

Back

myosin

Front

The neurotransmitter stored in the axon terminal identified as #3.

Back

Acetylcholine

Front

What is the role of troponin in muscle contraction?

Back

Troponin binds calcium ions, causing a conformational change that moves tropomyosin away from actin binding sites.

Front

What is the function of tropomyosin in muscle fibers?

Back

Tropomyosin blocks the binding sites on actin filaments, preventing muscle contraction until calcium binds to troponin.

Front

What is a sarcomere?

Back

The sarcomere is the basic structural and functional unit of muscle tissue, defined as the segment between two Z lines.

Front

What are the two main types of filaments in muscle contraction?

Back

Actin (thin filaments) and myosin (thick filaments).

Front

What is the role of ATP in muscle contraction?

Back

ATP provides the energy required for myosin heads to detach from actin and re-cock for another contraction cycle.