Answer: Do you have answer choices?
Explanation:
Natural selection is basically when organisms with the best traits survive and pass on their good traits to their offspring so that they will adapt easily and survive. Organisms who do not have ‘good traits’ that help them adapt and escape predators will be killed or eaten before they reproduce.
So in the end, natural selection is a form of evolution that allows the ‘fittest’ animals to survive and reproduce, while weeding out the unfit.
Answer:
c
Explanation:
Random distribution of the Isopods should be 50/50 in A and B.
Chi-square = 
where O = observed frequency and E = expected frequency
Chamber O E Chi-square
A 18 10 
= 6.4
B 2 10 
= 6.4
<em>Total Chi-square </em>= 6.4 + 6.4 = 12.8
<em>Degree of freedom</em> = 2 - 1 = 1
<em>Tabulated Chi-square</em> (α = 0.05) = 3.8415
The calculated Chi-square exceeds the critical value, hence, it is significant and not due to random.
<em>The correct option is </em><em>c</em><em>.</em>
Answer:
Unlike typical mammalian red blood cells, those from amphibians, such as frogs, contain a DNA-bearing nucleus that is visible in the center of the cell. The circulatory system of amphibians is rather unusual, their hearts having three chambers, two atria, and a single ventricle.
NegativePositive
Positive
The design of the amphibian circulatory system is curious because blood accumulates oxygen in the lungs and is then returned to the heart before being pumped into the rest of the circulatory system. Therefore, a mixing between oxygenated and deoxygenated blood occurs as blood returning to the heart from the lungs is mixed with incoming blood from the body. Frogs handle this situation by having a very slow metabolism and by absorbing some oxygen through their skin. In addition, the ventricle does have some directional control over the distribution of the blood.
Negative
The presence of a nucleus in amphibian red blood cells allows researchers easy access to large quantities of amphibian DNA. Frog blood has both a solid and a liquid portion. The liquid plasma carries solid elements such as red and white blood cells. Blood can be collected from frogs and the red blood cells isolated by centrifugation. After removal of the residual plasma, purified cells can be treated with specific enzymes and detergents to digest the cellular envelope and release DNA from its protein complex. The DNA is then useful for scientific studies and experiments.
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Explanation:
