The amount of energy required to initiate every metabolic reaction is called
activation energy.
enzyme energy.
cumulative energy.
work energy.
The Correct Answer is A
A. activation energy: Activation energy is the minimum amount of energy required to initiate a chemical or metabolic reaction. Enzymes lower this energy threshold, allowing reactions to occur more rapidly and efficiently at physiological temperatures, which is essential for sustaining life processes.
B. enzyme energy: There is no specific concept called "enzyme energy." Enzymes function by reducing activation energy, but they do not provide energy themselves; they act as catalysts to facilitate reactions.
C. cumulative energy: Cumulative energy is not a recognized term in biochemistry or metabolic reactions. Energy in metabolism is measured in terms of activation energy, free energy changes (ΔG), or ATP yield, not cumulative energy.
D. work energy: Work energy is a general physical concept referring to energy required to perform work but is not specific to initiating metabolic reactions. In biology, the energy to start reactions is specifically referred to as activation energy.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
A. Breakdown of molecules to release energy: Catabolism involves the enzymatic breakdown of complex molecules such as carbohydrates, lipids, and proteins into simpler molecules like sugars, fatty acids, and amino acids. This process releases energy, which is captured in the form of ATP to fuel cellular activities, making it a fundamental part of metabolism.
B. Building molecules: The synthesis of complex molecules from simpler ones is called anabolism, not catabolism. Anabolic processes, such as protein synthesis or glycogen formation, require energy input rather than releasing energy.
C. DNA replication: DNA replication is a specific cellular process that duplicates genetic material for cell division. While it is essential for cell survival, it is not a catabolic process, as it does not involve the breakdown of molecules for energy production.
Correct Answer is B
Explanation
A. uses CO₂ for its carbon source: Organisms that use carbon dioxide as their carbon source are called autotrophs, not heterotrophs. Autotrophs can synthesize organic compounds from inorganic carbon, whereas heterotrophs rely on preformed organic molecules.
B. must obtain organic compounds for its carbon needs: Heterotrophs cannot fix carbon dioxide into organic compounds, so they rely on consuming organic molecules such as carbohydrates, lipids, or proteins from other organisms. This dependency on external organic carbon distinguishes heterotrophs from autotrophs.
C. gets energy by oxidizing inorganic compounds: Organisms that derive energy from the oxidation of inorganic substances are chemolithotrophs. While some heterotrophs may also utilize chemical energy, the defining feature of a heterotroph is its requirement for organic carbon, not the energy source.
D. gets energy from sunlight: Organisms that capture energy from sunlight are phototrophs. While some phototrophs are autotrophs, heterotrophs rely on organic compounds for carbon and may use chemical energy rather than sunlight.
E. does not need a carbon source: All organisms require a carbon source to build cellular structures and macromolecules. Heterotrophs, in particular, must obtain organic carbon from their environment to survive and grow.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.