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:
The loss of trees and other vegetation can cause climate change, desertification, soil erosion, fewer crops, flooding, increased greenhouse gases in the atmosphere, and a host of problems for indigenous people.
Explanation:
Amino acid differs at the glutamine, which is converted to valine in hemoglobin S. the body produced hemoglobin S due to a point mutation in the DNA sequence which results in different amino acid to be formed during translation of DNA sequence codons.
Answer:
The greatest changes to the path and strength of the Gulf Stream might be caused by an increase in the volume of river water that flows into the Gulf of Mexico (Option B)
Explanation:
The North Atlantic current or Gulf Stream carries warm water from the Gulf of Mexico forward Europe, providing a relative template clime in most of the European occident.
Ocean streams are sensitive to the amount of freshwater available on the surface. An increase in overflow and precipitation over the ocean could slow or revert the north Atlantic current, blocking warm water flow to Europe.
The deposition of freshwater could cause a temporal deceleration or total collapse of the North Atlantic Current, and this interruption might lead to very cold periods in the North Atlantic.
