Metabolic rate is .
1. the total amount of energy an animal uses in a unit of time
2. the amount of heat lost by an animal in a unit of time
3. typically higher in an ectothermic animal than in an endothermic one
4. determined when the organism is at rest with an empty stomach
5. directly proportional to body size

Metabolic rate is the total amount of energy an animal uses in a unit of time (Option 1).

In conclusion, metabolic rate is the total amount of energy an animal uses in a unit of time (Option 1).

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Metabolic rate is the total amount of energy an animal uses in a unit of time

Explanation:

Hi, metabolic rate is the total amount of energy an animal uses in a unit of time.

It refers to how quickly fuels are consumed to keep the organism’s cells functioning.

Its unit of measure can be Joules, calories or kilocalories per unit of time.

Metabolic rate is proportional to the activity level. The More active the animals is , the higher the metabolic rate is.  

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the relative standard reduction potential of the half-cell in which reduction occurs; more positive than the other half-cell. reduction is a chemical process in which electrons are added to an atom or an ion; it always occurs accompanied by oxidation of the reducing agent.