When a muscle cell contracts some myosin heads bind to actin molecules as other myosin heads release from actin molecules.
Muscle contraction occurs when the thick filament and the thin filaments slide over one another in a series of repetitive events.
Answer:
This question lacks options, the complete question is: What do you think would have the greatest effect on the body—a harmful mutation in a pluripotent embryonic stem cell, or a harmful mutation in an adult multipotent stem cell?The correct answer is a harmful mutation in a pluripotent embryonic stem cell.
Explanation:
Pluripotent Stem Cells can self-renew and differentiate into any of the three germ layers, which are: the ectoderm, the endoderm and the mesoderm. These three germ layers subsequently differentiate to form all the tissues and organs within a human being. If during embryonic development, genetic mutations - alterations in genes - occur in the embryonic stem cell, they pass to daughter cells as a consequence of cell division, and an individual is generated whose cells differ at the genetic level. Multipotent stem cells are organospecific cells, that is, they can give rise to any type of cells but from a specific organ (a lung, a kidney or the brain). Their differentiation ends the moment they specialize and become a cell with a specific function within a specific tissue or organ. If there were a mutation in these cells, it would damage a specific designed tissue or organ.
Answer:
directional selection
Explanation:
Directional selection is the most common type of natural selection and occurs when some individuals with characteristics favorable to the conditions of the environment in which they live, have survival advantages over individuals who do not have this advantage, who end up dying.
Imagine, for example, a graph showing the directional selection in the same species of moths. Moths of the same species have white and brown collations, in summer, brown moths can camouflage themselves on tree trunks, while white moths cannot and are easily captured by their predators, which means that the amount of white moths decrease. In this graph, the population of white moths would be at a minimum, at the same time that the population of brown moths would be at maximum.
However, with the arrival of the reverse, snow begins to cover the trees, allowing white moths to camouflage themselves more easily. The brown moths, then, are very exposed to predators, causing their population to reach the minimum while the population of white moths reaches the maximum.
Answer:
Your bloodstream.
Explanation:
The cells in your pancreas produce insulin which needs to be sent to the rest of your body to tell your cells to take in glucose (sugar) for energy. In order to get sent out of the pancreas' cells, the insulin needs to go through your bloodstream.
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