Enhancers are eukaryotic DNA sequences that can be used to elevate transcription and have variable positions and orientations.
Answer:
Like coal and natural gas, petroleum was formed from the remains of ancient marine organisms, such as plants, algae, and bacteria. Coal, natural gas, and petroleum are all fossil fuels that formed under similar conditions. Today, petroleum is found in vast underground reservoirs where ancient seas were located.
<em><u>H</u></em><em><u>o</u></em><em><u>p</u></em><em><u>e</u></em><em><u> </u></em><em><u>t</u></em><em><u>h</u></em><em><u>a</u></em><em><u>t</u></em><em><u> </u></em><em><u>h</u></em><em><u>e</u></em><em><u>l</u></em><em><u>p</u></em><em><u>s</u></em><em><u>:</u></em><em><u>)</u></em>
Explanation:
The modern theory of chemical evolution is based on the assumption that on a primitive earth a mixture of simple chemicals assembled into more complex molecular systems, from which, eventually came the first functioning cell(s).
<h2><u>
Full Question:</u></h2>
In the family tree below, people with the recessive trait of attached earlobes are shaded gray.
What must be true about the person labeled "A"?
A. It is a male with at least one dominant allele.
B. It is a male with two dominant alleles.
C. It is a female with at least one dominant allele.
D. It is a female with two dominant alleles.
<h2><u>Answer:</u></h2>
Its a male with atleast one dominant allele.
Option A.
<h3><u>Explanation:</u></h3>
The gene for the attached earlobe is recessive while the gene for the free earlobes is dominant. In the phylogenetic tree, we can see that both the father and mother aren't having attached earlobes. So both of them are having atleast one dominant allele which makes them have free earlobe.
In the F1 offsprings, one of the female and a male is having free earlobes. So both of them have atleast one dominant allele. The 2nd female is having an attached earlobe. So both the recessive allele have come form one parent each. So both of them are heterozygous.
Thus, the male marked as A atleast have one dominant allele. He can be a homozygous dominant, but the probability is 25%.