Once a Pollen Tube Lands on a Compatible Stigma ____

question 18

Multiple Choice

Once a pollen tube lands on a compatible stigma ____.

• A) chemical cues guide the pollen tube from the stigma to the embryo sac of an ovule
• B) that pollen tube continues on to another ovule
• C) other pollen tubes are attracted to that ovule
• D) other pollen tubes can penetrate that ovule more easily
• E) the flower dies to prevent further pollination

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Definitions:

Sunrise

The time of day when the upper limb of the Sun appears on the horizon in the morning.

Sunset

The time in the evening when the sun disappears below the horizon, marking the transition from day to night.

Suprachiasmatic Nucleus

is a small region of the brain located in the hypothalamus that acts as the primary circadian clock, regulating sleep-wake cycles and other circadian rhythms.

Rhythmicity

The characteristic of exhibiting or pertaining to rhythm, often used in the context of biological processes and neural activity.