<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:
Explanation:
porque una persona con dos alelos normales presentará un fenotipo normal, mientras que si las dos copias del gen son el alelo mutado que producen una enfermedad, el fenotipo expresará los síntomas característicos de esa enfermedad.
It is an organic substance.
Answer:
Productivity is refers to the rate of generation of biomass in an ecosystem. The difference between net and gross productivity is that gross productivity is is the overall rate of energy capture while net productivity is is lower, adjusted for energy used by organisms in respiration/metabolism.
Explanation:
