contraction
Definition
Contraction is a process in which the length of a muscle fibre decreases.
This is caused by the sliding of actin and myosin filaments past each other, which is powered by the hydrolysis of ATP.
Contractions can be isometric, in which the muscle length does not change, or isotonic, in which the muscle length changes.
How can the word be used?
The doctor prescribed a medication to contract the blood vessels.
Different forms of the word
Noun: contraction.
Verb: contract.
Adjective: contractive.
Etymology
The word "contraction" comes from the Latin word "contractio," which means "drawing together" or "shrinking." It is made up of the prefix "con-," which means "together," and the verb "trahere," which means "to draw.".
Question
What things can contract?
AQA Science Exam Question and Answer
Question:
Describe the process of muscle contraction and its role in body movement.
Answer:
Muscle contraction is the process where muscle fibres shorten and generate tension, leading to the movement of body parts. It occurs when muscle fibres receive signals from motor neurons, causing the release of calcium ions, which activate proteins to slide past each other, resulting in muscle shortening and movement. Muscle contraction is essential for various body movements, such as walking, running, and lifting objects, enabling us to perform daily activities and physical tasks.