Incomplete dominance is where two traits intermix together, usually to create some kind of in-between trait. With blonde hair and black hair, the offspring will likely have a hair color that will be between the two extremes — likely brownish hair. There will be patches or strands of pure blonde and pure black hair in the offspring if hair trait was co-dominant, but it states in the problem that hair color trait has incomplete dominance. It may also be possible that the child will have only blonde hair or only black hair, but this is less likely and also will not be demonstrating the concept of incomplete dominance, as the question is asking for. Any of the other answers are equally likely to occur since the two parents have very different hair colors.

It can be seen that the phenotypic ratio of the offspring will be purple : pink of 2 : 2. This can be seen by doing a Punnett square and keeping in mind that fur color in this problem has incomplete dominance.

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It is possible for the parents to have genotypes that contain recessive alleles that will yield an offspring with the recessive traits. This can be seen by doing a dihybrid cross of the two parents both with genotypes of TtRr (which would express sharp teeth and red leaves; additional note: both parents HAVE to have this genotype in order to have an offspring with the recessive traits of blunt teeth and purple leaves — please refer to the Punnett square to see why).

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Restriction enzymes are named from the organism they were taken from. They function to cut DNA in bacteria, a crucial step in the process of sequencing DNA, as you need it to be broken down into smaller segments.

There are two primary factors that influence the quality of a polymerase chain reaction (PCR) primer. The first is length. The primer should ideally be roughly 18-30 bases in length; this qualification can be used to rule out two of the possible given answer options. The second factor is the melting point of the primer. An ideal oligonucleutide sequence will have a relatively high cytosine/guanine content. These particular bases form three hydrogen bonds in the DNA molecule, while adenine and thymine form only two. Cytosine and guanine interactions thus require more energy to break, and raise hte melting point of the sample. The process of PCR requires heating the sample at certain points, which can become a problem for primers with high adenine/thymine content.

Our ideal answer will be a longer sequence (18 bases) with a high percentage of cytosine and guanine residues.

It was Gregor Mendel who did studies on pea plants to first described the concepts behind genetic inheritance. By breeding pea plants with different visible phenotypes and observing the phenotypes of the offspring produced, he was the first scientist to provide rules for heredity (now known as Mendelian inheritance). 

Polymerase chain reaction (PCR) is a method by which a specific sequence of DNA can be copied and replicated many times over in a test tube, which has been of enormous importance to the field of molecular biology. The other techniques listed all are important in molecular biology as well, but are typically for detection or other manipulations, not replication. 

Watson and Crick crystallized DNA to be able to visualize the structure, and it was this finding that led them to propose the double helix. Fun fact: Rosalind Franklin's work was essential to this finding as she was the expert in x-ray crystallography, but Watson and Crick are traditionally given all the credit. 

This process is known as transformation. It was discovered after Griffith heat treated bacteria (to destroy their virulence) and noticed that mice injected with the heat-killed bacteria and a living, non-virulent strain would die of infection.

In 1910, Thomas Hunt Morgan performed a test cross between white-eyed male Drosophila and homozygous red-eyed females to test the frequency of white eyes in the subsequent generations. The F1 generation all had red eyes, but when Morgan crossed the F1 generation, he noticed a 3:1 ratio of red to white eyes in the F2 generation. In all of his experimements, the white-eyed F2 flies were always male. Subsequent experiments supported the hypothesis that the white-eye trait was sex-linked (in this case, to the X chromosome).