The answer is an open system
Answer:
Answer is A signal is sent down an exon within a nerve cell.
Explanation:
<span>a. Fish have a single central heart; earthworms have several hearts.
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Multi cellular organisms are made up of billions of cells each specialized to a unique role and these cells are organized into structural and functional units such as tissues and organs.
For each cell and organ to function optimally, it requires oxygen and nutrients and needs carbon dioxide and metabolic waste taken away in a continuous, never ending process.
<span>A mechanism is needed to accomplish the important function of transporting the relevant materials to and from the cell. The circulatory system fits this bill splendidly. It is a specialized organ system which allows blood and lymph to flow through the entire body carrying nutrients such as glucose, amino acids and electrolytes as well as oxygen to each cell, at the same time carting away carbon dioxide and all sorts of metabolic waste over to excretory organs to be expelled from the body.
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<span>B. the creation of two daughter cells with half the number of chromosomes that the parent cell has by the process of cell division
</span><span>D. The exchange of solute molecules across a permeable membrane from areas of high concentration to areas of low concentration
</span><span>A. Osmosis occurs through a semipermeable membrane. Diffusion occurs through a permeable membrane.</span>
Since there are 20 heigh-associated genes and only two of the alleles are identical to both of them, the other genes could have different effects on the development of their bone and muscle cells which can result to the two women having different heights.