Xylem Vessels, Found in Angiosperms, Have a Much Greater Internal

question 20

Multiple Choice

Xylem vessels, found in angiosperms, have a much greater internal diameter than tracheids, the only xylem conducting cells found in gymnosperms. The tallest living trees, redwoods, are gymnosperms. Which of the following is an advantage of tracheids over vessels for long-distance transport to great heights?

• A)Adhesive forces are proportionally greater in narrower cylinders than in wider cylinders.
• B)The smaller the diameter of the xylem, the more likely cavitation will occur.
• C)Cohesive forces are greater in narrow tubes than in wide tubes of the same height.
• D)Only A and C are correct.
• E)A, B, and C are correct.

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Definitions:

Size Constancy

A perceptual process allowing individuals to perceive the size of an object as constant, despite changes in the distance or angle from which it is viewed.

Perceived Size

The size an object appears to have in the viewer's perception, which can be influenced by distance, context, and conditions of observation.

Phi Phenomenon

A visual illusion in which stationary objects shown in rapid succession, such as in a motion picture, appear to be moving.

Stroboscopic Motion

Perceived motion created by the rapid presentation of static images in sequence, similar to how motion pictures work.