Because the three-horned alien is heterozygous, we know that three must be dominant to four, because the gene for the three horns is "hiding" the gene for four horns. Therefore, the three-horned alien has the genotype Tt (T for three horns, and t for four horns). The four horned alien must be tt, because that is the only way that a recessive trait may be seen. If you solve the punnet square on a cross between Tt and tt, you end up with half three (heterozygous) and half four (homozygous recessive) it is a bit easier to explain with something a little "closer to home" if you want me to explain it again, just say so, I don't mind!
Can you please elaborate..?
Graduated Cylinder. A graduated cylinder measures volumes of liquids.
Answer:
Primitive Earth where life emerged was subjected to extreme conditions
Explanation:
The origin of life is still an issue of intense debate today, although most researchers believe that life emerged from primitive organisms generated by the synthesis of organic compounds in early Earth. In line with this theory, it has been shown that membrane-forming compounds can be formed in extreme conditions (i.e., UV rays, extreme temperature, etc). It is believed that such conditions recreated in a laboratory were similar to the early Earth about 3,900 million years ago, thereby supporting the idea of the 'primordial soup theory' proposed by John Burdon Sanderson Haldane in 1929.
