It is when their is sort of a dent somewhere on your body, dimples are usually found on the face, and sometimes you may only have a dimple on one side of your face
I believe is that one is salt water and the other is maybe regular water, salt water will shrink cells
<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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The human body is made up of four different types of tissues, these are epithelial, muscular, connective and nervous tissues. Epithelial tissues refers to the thin tissues, which covers all the exposed surfaces of the human body. They can be found in the following places: digestive tract, inner lining of the mouth, secretory glands, external skin, the lining of hollow part of the heart, etc. The cells of epithelial tissues are usually closely bound together and they lack blood vessels and nerves.
