Answer: Since nutrients are needed to build life tissues and carry out essential life functions, a limiting nutrient (scarce nutrient) will limit organisms' growth in an ecosystem.
YES.The distribution of bases in sea urchin DNA and salmon DNA follow Chargaff's rules because the percentage of A bases is approximately equal to the percentage of T bases, and also the percentage of G bases is approximately equals to the percentage of C bases in both species. According to Chargaff's rule the amount of guanine should be equal to cytosine and the amount of adenine should be equal to thymine.
Answer and Explanation:
As I don't have access to live butterflies, the control group would be clay models that do not exhibit warning coloration, e.g. beige / white / brown. In contrast, the experimental group would be the clay models that exhibir a strong warning coloration such as color orange / red.
After preparing the clay 'prey', I would locate them in specific places outside where birds are able to detect them. Moreover, I would use a webcam to monitor the recurrence of birds in the area.
1st experiment: Test whether birds approach the prey that exhibits both warning coloration (experimental group) and dull coloration (control group). Then, record the minutes they spent wandering near the prey.
2nd experiment: Test wheter birds feed on the prey that exhibits both warning coloration (experimental group) and dull coloration (control group). Record time.
Carry out statistical analyses.
Present results and discuss.
Answer:
geographical isolation
Explanation:
Reproductive isolation is a process of evolution that ensures that members of different species are incapable of mating and when they do, such mating do not result into any offspring or leads to the production of invalid offspring.
There are two mechanisms of reproductive isolation:
- Pre-zygotic mechanisms prevents fertilization between two different species and these include habitat isolation, mating seasons, mechanical isolation, gamete isolation, geographical isolation and behavioral isolation.
- Post-zygotic isolation prevents the products of fertilization from becoming valid and this include hybrid inviability, hybrid sterility and hybrid breakdown.
<em>Geographical isolation involves the existence of geographical barriers between two populations such that there cannot be mating between the two. The two populations eventually evolve to become different species.</em>
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Answer:
b. False
Explanation:
These components are not sufficient to successfully perform a PCR reaction. Deoxynucleoside triphosphates (dATP, dGTP, dCTP, dTTP) are missing so that the PCR reaction can occur perfectly.
The PCR technique allows a specific fragment of the DNA molecule to be amplified thousands of times in just a few hours. This technique revolutionized research in molecular biology because it had taken a long time for DNA amplification. From PCR it is possible to obtain enough copies of a part of DNA to detect and analyze the sequence that is the target of the study.
For a PCR reaction to be performed a solution with some components must be prepared. These components are:
- Magnesium chloride buffer (to optimize reaction and act as a cofactor for polymerase)
- Forward and reverse primers (to customize the start of the enzyme reaction)
- DNA polymerase (Enzyme required for replication of desired DNA region.)
- DNA Template (the DNA to be copied)
- PCR-grade water
- Deoxynucleoside triphosphates: dATP, dGTP, dCTP, dTTP (act as bricks in the construction of DNA molecules).
