Answer: An Organ System
Explanation: Vascular plants have two distinct organ systems: a shoot system, and a root system. The shoot system generally grows above ground, where it absorbs the light needed for photosynthesis. The root system, which supports the plants and absorbs water and minerals, is usually underground.
Answer:
Unconditioned stimulus.
Explanation:
Classical conditioning may be defined as a type of learning procedure in which the biological procedure is used to pair up with the previous nerve stimulus. This stimulus result in the response of an individual.
The Pavlov experiment with the dog explains the process of classical conditioning. The ringing of bell (conditioned stimulus) is paired with unconditioned stimulus (meat presentation).
Thus, the meat presentation is unconditioned stimulus.
World pollution isn’t good
D.mitochondria because animal cells also contain mitochondria