A taxonomist is someone who classifies animals, plants, and other organisms into their respective kingdoms, allowing the earth to be separated into different types of things. The conservation of habitats is one of the most important factors to a taxonomist because organisms are found only in specific areas/habitats. If these areas were to be destroyed, it is possible that unclassified species could be destroyed along with it, causing the taxonomist to be unable to discover them and share them with the world.
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.
