<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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Answer: C. A substrate
Explanation:
A substrate is a substance on which an enzyme act. The enzyme acts on substrate X and converts it to Y.
Usually, volcanic ashes and cooled lava contain different minerals that plants can use. Therefore, usable.
Answer:
W w X w w
Explanation:
the square would fill with
Ww. ww
Ww. ww
<u>Answer</u>: C. Neutralization of stomach acid.
Hydrochloric acid is one of the three components of the stomach acid. The other two are potassium chloride and sodium chloride.
It plays a key role in the destruction of some ingested microorganisms. It is also vital to the digestion of proteins by activating the enzyme pepsin.
