In this virtual lab activity, you will be observing the cell cycle at the tip of an onion root. The root tip is responsible for the downward growth of the root and is one of the regions in the plant where cells are actively dividing and growing. Because of this, the root tip is an excellent system in which to observe the entire cell cycle, including the processes of nuclear division (mitosis) and cell division (cytokinesis).

metamorphism is the change of minerals or geologic texture (distinct arrangement of minerals) in pre-existing rocks (protoliths), without the protolith melting into liquid magma (a solid-state change). the change occurs primarily due to heat, pressure, and the introduction of chemically active fluids. i hoped i !

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms