​Which Bases Are Pyrimidines

question 7

Multiple Choice

​Which bases are pyrimidines?

• A)​cytosine and thymine
• B)​guanine and thymine
• C)​guanine and cytosine
• D)​adenine and guanine
• E)​adenine and thymine

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Definitions:

Phosphate

A chemical compound that contains the phosphate ion (PO4^3-), which is essential in biological systems for energy transfer and storage.

Intracellular Buffer System

Mechanisms within cells that regulate pH levels, preventing significant variations that could otherwise interfere with cellular function.

Sodium-Potassium Pump

A cellular mechanism that moves sodium ions out of and potassium ions into a cell against their concentration gradients, essential for cellular functions.

Carbonic Acid/Bicarbonate System

A major buffer system in the blood, maintaining the body's pH balance by regulating carbon dioxide (CO2) and bicarbonate (HCO3-) levels.