Of the Four Major Earth Systems,which One Is Composed of Living

question 4

Multiple Choice

Of the four major Earth systems,which one is composed of living organisms?

• A) atmosphere
• B) hydrosphere
• C) lithosphere
• D) biosphere

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Definitions:

Blood Pressure

The force exerted by circulating blood on the walls of blood vessels, typically measured as systolic (pressure during heartbeat) and diastolic (pressure between beats) values.

Conditioning

The process of training or accustoming a person or animal to behave in a certain way or to accept certain circumstances.

Neurofeedback

A type of biofeedback that uses real-time displays of brain activity, typically through EEG, to teach self-regulation of brain functions.

Positron Emission Tomography

A nuclear medicine functional imaging technique used to observe metabolic processes in the body by detecting pairs of gamma rays emitted indirectly by a positron-emitting radionuclide.