Answer: If one is constructing a phylogeny of reptiles using DNA sequence data of birds, mammals, amphibians or fish, the suitable outgroup to be used are mammals due to the time of divergence from other group of organisms.
Explanation: Phylogeny is used to determine evolutionary relationship between items or organisms. A phylogenetic tree is a graphical illustration of phylogenetic relationship. In phylogeny, an outgroup represent an organism that is more distantly related to other group of organisms.
In a phylogenetic tree, outgroup stands alone. It shows that the time of divergence of that particular organism is far from other group of organisms. Outgroup is used to root a tree and sometimes represent a group that is more ancestral on a tree.
It should be noted that differences in the DNA sequences of the organisms under consideration will determine which organism will serve as the outgroup.
Answer : Option D) Fewer people have skin pigmentation lighter than the central peak than people who have pigmentation darker than the central peak.
Explanation : The quantitative variation which is shown for the skin is best explained by option D. Which shows that fewer people have got skin pigmentation which is lighter than the central peak in the graph, compared to the people who have darker pigmentation than the central peak.
Anti- inflammatory combined with a local anesthetic that offers short term pain relief for degenerative disc disease. So a positive effect , in some cases saline can flush out chemicals that can cause the inflammation providing even more pain relief.
Dominance involves one allele masking another at the same locus whereas epistasis involves one locus masking a different locus.
Explanation:
Epistasis is a type of gene interaction in which one gene masks or modifies the expression of another gene at a distinct locus.
Dominance refers to the gene interaction in which one allele of a given gene masks the expression of another alllele of same gene.
The comparison of dominance and epistasis give the following information:
- Dominance involves allelic suppression while epistasis involves non-allelic suppression.
- Dominance involves a single pair of alleles while epistasis involves two pairs of allele.
- In dominance, the expression of recessive allele is suppressed while in epistasis, either recessive or dominant non allele is suppressed.
- The effect of dominance is due to the dominant allele while epistasis may be due to dominant or recessive allele.
Answer:
The question: Do mice live longer when they are fed high sugar diets?
Hypothesis: There are two hypothesis the null hypothesis which we assume is correct, it states that a high sugar diet will have no effect on the life span of a mouse and an alternate hypothesis that we accept if evidence shows that sugar does increase the life span if mice. It says a high sugar diet does incerease the life span of mice.
Prediction: Assume that the null hypothesis is correct. High sugar diets will not increase the life span of the mice.
Collect data through experimentation. Use some mice as a 'control'. These mice will not undergo any changes but will be kept for comparison. Expose some other mice to high sugar diets and the compare the outcome with the 'control' mice.
Analyzing: From the experiment this you can choose which hypothesis you are going to accept. I.e. null: no change or alternate: there was a change and do some extra research to back up your hypothesis.
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