Answer:
Option c (No, T cells left from the previous infection can kill any virus.
)
Explanation:
When ever viral infection occur, body's immune system start to fight against it by activating B-cells and T-cells.
B-cells produce antibodies that bind with virus and act as label. This label indicate virus as foreign substance. Hence T-cells recognize it and kill it. Furthermore, B-cells form memory cell that keep the viral memory. if this viral infection occur again in future, T-cell recognize it and eliminate the virus.This mechanism is called immunity.
A. the cell is the smallest working unit of living things
Answer:
Delivered small RNAs can inhibit protein A production through the RNA interference (RNAi) mechanism, and thus impairs angiogenesis
Explanation:
The pregnancy-associated plasma protein-A is a protease enzyme involved in the formation of new blood vessels by increasing insulin-like growth factor I (IGF-I) bioavailability. Moreover, small RNAs (<200 nucleotides in length, generally 18 to 30 nucleotides) are non-coding RNA molecules that function in RNA silencing through the RNA interference (RNAi) pathway. Small RNAs are widely used in molecular biology laboratories because they can be delivered into specific cells in order to silence target mRNAs such as, in this case, the mRNA encoding protein A, by complementary base pairing and thereby inducing translational repression. In consequence, mRNAs complementary to delivered small RNAs are silenced through RNAi pathways, i.e., by cleavage of the target mRNA and/or mRNA destabilization.
Some of the main functions of skin cells are to provide protection, perceive and transmit sensation, control evaporation and regulate temperature.<span> Skin cells, which are epithelial cells, are also self-repairing and reproduce quickly.</span>
