Answer:
Option-C
Explanation:
A pulse-chase experiment which is used to study the cellular process taking place in the cells. This uses the labelled molecule which is incorporated into the cellular pathway and then the unlabeled molecules are used over time to determine how much time is required by the unlabeled molecule to replace the labelled molecule.
In the given question, the pancreatic cell which secretes the digestive enzyme known as the acinar cell is labelled with the leucine and then used unlabeled leucine.
When observed after three hours, the black spots will appear on the exterior of the cell as the protein has been synthesised by the ER and now has been secreted from the cell.
Thus, Option-C is the correct answer.
Answer:
The correct answer would be - "bacterial populations evolve in response to the selection pressure imposed by antibiotics".
Explanation:
The given information provided in the question about the bacterial infection supports the hypothesis that the bacterial population shows the evolution in response to the selection pressure caused by the antibiotics due to the fact that bacteria increased resistance gradually with time. This resistance towards antibiotics increased the percentage of bacterially infected children in the late 1980s and early 1990s.
In this case, the population of bacteria having resistance genes is selected to evolved selected to increase their offsprings.
The right answer is D (less responsive to antigens)
It is proven that, after puberty, thymus activity (an organ that is included in the lymphatic system, producing T cells that pick up antigens) decreases and that in adult and aged people the thymus has no role. Work done in humans indicate that in fact the cellularity begins to decline from birth in favor of lymphocyte perivascular spaces and connective and adipose tissue, which leads to a decrease in the capture of antigens.
The basic repeating unit of nucleic acids are known as nucleotides. A nucleotide consists of three distinct chemical groups, a 5-carbon sugar (ribose or deoxyribose), a nitrogen-rich base - (cytosine (C), guanine (G), adenine (A), thymine (T) in DNA or uracil (U) instead of T (in RNA), and phosphate.
