In artificial selection, nature provided the variation, and human selected those variations that they found useful
<span>A. The nebula contracts and shrinks instead of expanding
</span><span>Nebula is the cloud of interstellar dust and gas that forms a star. It is collborately shaped during colliding and collapsing of the interstellar mediums this is influenced by the gravitational attraction of the atoms and particles in the entites. Hence, there are three types of nebular namely, are classical nebula, diffuse nebula, planetary nebular and supernova remnants.</span>
There are 5 main types of pathogens that can harm other organisms and cause diseases. They are viruses, bacteria, fungi, Protozoa, and worms.
Maintenance of normal sinus rhythm
antidysrhytmic drugs are used to treat abnormal rhythm of the heart. Abnormal rhythm is usually due to the irregular electrical stimulation of the electrical activity of the heart. This can work by correcting the cardiac function there are four classes of this drugs such as Class I for sodium channels, Class II which are the beta blocker, Class III which are the drugs that prolong repolarization and Class IV which are the calcium channel blocker.
Explanation:
SARS, Ebola, swine flu, rabies