Answer:
An asteroid impact.
Explanation:
An asteroid impact is considered to have tossed rubble across the earth, killing off many species of plants and animals, 65 million years ago. Volcanic activity is involved in at least four mass extinctions, whereas an asteroid in just one.
<span>Definition of a hydrogen bond is an electrostatic attraction between two polar groups that occurs when a hydrogen atom covalently bound to a highly electro negative atom such as nitrogen, oxygen, or fluorine experiences. Hope this helps </span>
A. Water being pumped in and out of guard cells.
A chromosome is DNA wrapped around proteins knwn as histones. A gene is a part of the DNA that codes for a particular protein
Answer:
Los organismos unicelulares se componen de una sola célula que lleva a cabo todas las funciones necesarias por el organismo, mientras que los organismos multicelulares utilizan muchas células diferentes para funcionar.