A Stem Is Observed to Increase in Diameter from One

question 176

Multiple Choice

A stem is observed to increase in diameter from one April to the next.A cross section of the stem will show that the diameter increased because

• A) primary xylem cells divided.
• B) phloem cells divided.
• C) primary xylem cells elongated.
• D) vascular cambium cells divided.
• E) phloem cells elongated.

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Definitions:

Melatonin Secretion

The release of melatonin, a hormone regulated by the pineal gland, which influences sleep-wake cycles and circadian rhythms.

Half-Lives

The time required for a quantity to reduce to half its initial amount, often used to describe the decay of radioactive substances or the elimination of drugs from the body.

Lipid-Soluble

Refers to a substance's ability to dissolve in fats, oils, and non-polar solvents.

Rapid Onset

A situation or condition that develops or occurs suddenly and progresses quickly.