Actin

question 108

Multiple Choice

Actin

• A) does not perform a power stroke during muscle contraction
• B) contains a globular head that forms the cross bridges between the thick and thin filaments
• C) is not found within A bands
• D) is inhibited by Ca²⁺
• E) none of these

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Definitions:

Tertiary Consumer

An organism that typically eats secondary consumers, residing at or near the top of a food chain and usually a carnivore or an omnivore.

Ecological Efficiency

A measure of the energy transfer between different trophic levels in an ecosystem, typically representing how much energy from a lower level is available for use at the next level.

Trophic Level

The position that an organism occupies in a food chain, which is a measure of its feeding level.

Decomposers

Organisms, such as bacteria and fungi, that break down dead organisms and waste materials into simpler substances.