<span>the action of forming a united whole</span>
The urinary tract collects and stores urine and provides a passage for urine to be expelled from the body. The ureters are about 25-30 cm long and carry urine from the kidneys to the bladder.
<span>The anterior end of an earthworm contains an organ that detects smells. Evidence of this is the way the earthworms responded to the ammonia. The earthworms backed away from the ammonia when it was waved near their anterior end, but they did not respond at all when the ammonia was waved near their posterior end.</span>
Answer:
color of light
Explanation:
<em>The independent variable is the variable that is supplied and often varied/manipulated by the researcher during the course of experiments. It is varied/manipulated in order to see the effect it will produce on another experimental variable - the dependent variable.</em>
In this case, out of all the variables supplied by Mary, only the color of light supplied was varied - red, white, green, and blue; other variables supplied were kept constant. Hence, <u>the independent variable is the color of light.</u>
This means that a single carbon atom can form up to tetravalent bonds with other atoms