Compared with Young Trees Growing Out in the Open, Young

question 5

Multiple Choice

Compared with young trees growing out in the open, young trees growing in a darker forest understory tend to have longer, thinner trunks with less branching.This developmental pattern is principally caused by

• A)phototropism.
• B)thigmotropism.
• C)activated phytochrome being converted to inactive phytochrome.
• D)inactive phytochrome being converted to active phytochrome.
• E)none of these.

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Definitions:

Chemical Name

A term that provides the scientific and technical information about the chemical composition and molecular structure of a substance.

Hypochondriac

A person excessively worried about having a serious illness, often with no basis for such concerns.

Lumbar

Relating to the lower part of the back or the lower spine between the thoracic spine and the sacral region.

Iliac

Pertaining to the ilium, the largest bone of the pelvis.