Answer:
Option (a).
Explanation:
Counter current flow may be defined as the flow of water in the opposite direction with the flow of blood in the body. This countercurrent flow is generally occurs in fishes.
The one main benefit of the countercurrent flow is the absorption of maximum oxygen as the water flows inside the body. Approximately, three time more oxygen is extracted during the counter current flow. The concentration gradient is maintained up to the whole length of gills.
Thus, the correct answer is option (a).
DDT was one of the first chemicals in widespread use as a pesticide. Following World War II, it was promoted as a wonder-chemical, the simple solution to pest problems large and small. Today, nearly 40 years after DDT was banned in the U.S., we continue to live with its long-lasting effects:
Interspecific competition can occur between two different species competing for the same resource in an ecosystem. So for this particular bug population, there may be another insect species that competes for the same food source or another resource, such as material or space for breeding habitat. This can lead to selective pressure, and may result in the different species evolving a more specific diet or inhabiting a niche environment.
Answer:
Option B) Serine-Phenylalanine-Aspartic acid
Explanation:
mRNA codons AGC code for the amino acid, serine while UUC code for phenylanine and GAU code for aspartic acid.
Thus, the resulting amino acid sequence after translation will be a tripeptide containing Serine-Phenylalanine-Aspartic acid
