Answer:A. The release of calcium ions causes myosin and actin to attach to each other.
The contraction of skeletal muscles takes place by induction of a nerve impulse, which produces a movement and the interaction of the filaments containing proteins named as actin and myosin. This interaction of filaments is regulated by proteins called tropomyosin and troponin present on the actin filaments. The motor nerve causes the depolarization of the muscle membrane sarcolemma. This triggers the sarcoplasmic reticulum to release calcium ions. This calcium binds to troponin and thus allows the tropomyosine strand on the actin filament to displace so that the part of the actin where myosine head needs to be attached remain uncovered. Binding of the actin myosine filament results in contraction.
Hence, the release of calcium ions causes myosin and actin to attach to each other causes muscle contraction.
Answer:
Do you think there is a quantitative relationship between transpiration rate and number or size of leaves on the stem? Explain your answer. Yes, the more leaves a plant has, means more stomata will be available for transpiration. ... Without light to facilitate photosynthesis, most plants close their stomata at night.
Explanation:
Answer: Sudden loss of habitat
Explanation:
Endangered species are animal or plant species that are in danger of going extinct.
This usually results from them suddenly losing their habitat and thus being exposed to unfamiliar conditions or threats that could end their existence. For instance, elephants losing their forest habitats in India and thus encroaching on farmland only to get shot for damaging farms.
The answer is D.) the process where distribution of molecules is balanced out by their movement.