Chapter 5 & Muscle contraction

Front

What is muscle contraction?

Back

Muscle contraction is the process by which muscle fibers generate force and shorten in length, allowing movement of body parts.

Front

Define endergonic reaction.

Back

An endergonic reaction is a chemical reaction that requires an input of energy to proceed, resulting in products that have higher energy than the reactants.

Front

Define exergonic reaction.

Back

An exergonic reaction is a chemical reaction that releases energy, resulting in products that have lower energy than the reactants.

Front

What role does calcium play in muscle contraction?

Back

Calcium ions bind to troponin, causing a conformational change in tropomyosin, which allows myosin to bind to actin and initiate muscle contraction.

Front

What is ATP and its role in muscle contraction?

Back

ATP (adenosine triphosphate) is the energy currency of the cell, providing the energy required for muscle contraction and relaxation.

Front

What is an allosteric inhibitor?

Back

An allosteric inhibitor is a molecule that binds to an enzyme at a site other than the active site, causing a change in the enzyme's shape and reducing its activity.

Front

What is acetylcholine?

Back

Acetylcholine is a neurotransmitter released at the neuromuscular junction that stimulates muscle contraction by binding to receptors on muscle cells.

Front

What is the sarcolemma?

Back

The sarcolemma is the cell membrane surrounding a muscle fiber, playing a crucial role in conducting electrical impulses.

Front

What are transverse tubules?

Back

Transverse tubules (T-tubules) are extensions of the sarcolemma that penetrate into the muscle fiber, facilitating the transmission of action potentials.

Front

What is the function of the sarcoplasmic reticulum?

Back

The sarcoplasmic reticulum is an organelle that stores calcium ions and releases them during muscle contraction.