<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>1. temperature
2.water purification
3. succession
4. alien species
5. conduct a survey of a species population in an ecosystem
6. adopt ecological conservation practices</span>
Answer:
At least 6. You have to look at the chemical formula for cellular respiration and make sure it is balanced!
C6H12O6+6 O2→6 CO2+6 H2O
Explanation:
Answer:
Five planets — Mercury, Venus, Mars, Jupiter, and Saturn were known to the ancients. ... However, the planets moved relative to the stars. For this reason they were called wandering stars. Our word "planet" comes from the Greek word planetes, meaning "wanderer
Explanation:
Answer:
I'm not sure how to help with this question because there was not enough information given.