When a Weak Stimulus Is Applied in Rapid Succession, It

question 116

Multiple Choice

When a weak stimulus is applied in rapid succession, it will often reach threshold due to

• A) voltage potential.
• B) spatial summation.
• C) temporal summation.
• D) excitatory summation.
• E) inhibitory summation.

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Definitions:

Angiosperms

A large group of plants characterized by having flowers and producing seeds enclosed within a fruit.

Xylem

Complex vascular tissue of plants; cell walls of its dead tracheids and vessel elements form tubes that distribute water and mineral ions through the plant body.

Tracheids

Component of xylem. Tapered cells that die when mature; pitted walls that remain interconnect with other tracheids to form water-conducting tubes.

Vessel Elements

Of xylem, cells that form in stacks and die when mature; their pitted walls remain to form water-conducting tubes. Each tube consists of a stack of vessel elements that meet end to end at perforation plates.