Select all of the answers that apply. dark matter may be
superhot gas between stars
cold matter that emits little radiation
the cause of the expansion of the universe
a new form of subatomic particle
the material from which living things develop

any abiotic or biotic factor in an ecosystem that causes a population's size to slow or decrease is a limiting factor.

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

air enters through the nose, moves through the nasal cavity, the pharynx, the larynx, enters the trachea, moves through the bronchi andbronchioles till the alveoli.