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, Nutrition
the process by which nutrients are acquired from the environment and used in cellular
activities such as metabolism and growth.
Nutrient
any substance that can be metabolized by an organism to give energy and build tissue.
Essential nutrient
A nutrient that cannot be synthesized by the body and must be supplied in the diet.
Macronutrient
A chemical substance that an organism must obtain in relatively large amounts, which
plays principal role in cell structure and metabolism. Ex. C, N, P.
Micronutrient
A substance needed only in small amounts for normal function of an organism. They are
involved in enzyme function and protein maintenance. Ex. Mn, Zn, Ni.
Photoautotroph
organism that uses energy from sunlight to convert carbon dioxide and water into organic
compounds which store energy in their chemical bonds.
Chemoautotroph
an organism that needs only carbon dioxide as a carbon souce but that obtains energy by
oxidizing inorganic substances
Lithoautotroph
a chemoautotroph that requires neither sunlight nor organic nutrients, relying totally on
inorganic minerals
Chemoheterotrophs
An organism that must consume organic molecules for both energy and carbon.
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,page2
, Nutrition
the process by which nutrients are acquired from the environment and used in cellular
activities such as metabolism and growth.
Nutrient
any substance that can be metabolized by an organism to give energy and build tissue.
Essential nutrient
A nutrient that cannot be synthesized by the body and must be supplied in the diet.
Macronutrient
A chemical substance that an organism must obtain in relatively large amounts, which
plays principal role in cell structure and metabolism. Ex. C, N, P.
Micronutrient
A substance needed only in small amounts for normal function of an organism. They are
involved in enzyme function and protein maintenance. Ex. Mn, Zn, Ni.
Photoautotroph
organism that uses energy from sunlight to convert carbon dioxide and water into organic
compounds which store energy in their chemical bonds.
Chemoautotroph
an organism that needs only carbon dioxide as a carbon souce but that obtains energy by
oxidizing inorganic substances
Lithoautotroph
a chemoautotroph that requires neither sunlight nor organic nutrients, relying totally on
inorganic minerals
Chemoheterotrophs
An organism that must consume organic molecules for both energy and carbon.
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