Answer:
Mutations are permanent changes in the DNA due to changes in nucleotide sequences. Mutations that cause addition of extra nucleotides in a nucleotide sequences are known as frameshift mutations
Answer:
D. Cytosol
Explanation:
A. Ribosomes are involved in protein synthesis
B.Cell Membrane is the part of the cell that encapsulates the cell
C. Cell Walls are what encapsulates plant cells
Answer:
Water is a liquid. Water is not wet BECAUSE something is only wet when water is on that object.
Explanation:
For example, there is water is a glass cup, and then the glass cup spills onto the table, causing the table to be wet, BUT you can remove that water from the table with some paper towels or a rag. Therefore, the table is no longer wet. Or when you're out in the rain and it gets on your clothes and/or hair, then your clothes and/or hair is WET.
When you put water onto water, it's an addition of water, you don't say it's wet or wetter.
Now, let me further prove my point with a different element: Fire. Fire burns things, right? So, when fire is on an object, then that object is burned. And when you add fire to fire, it causes more fire; fire does not burn itself.
Therefore, water is NOT wet. Wet is an adjective to describe an object that has been touched by a liquid, in this case, water.
So, yeah, enjoy the rest of your day. I'm sure some would like to argue my point. Go ahead.
Answer:
b). activation of T cells
Explanation:
An APC (antigen-presenting cell) can be described as an immune cell, which detects, uptakes, and informs the acquired immune response when an infection takes place. B cells, macrophages, and dendritic cells are antigen-presenting cells.
These cells play an important role in activation of T cells. T cells are unable to recognize soluble or free antigens and can only recognize antigens processed and presented by carrier molecules, such as MHC molecules.
Presence of MHCII molecules is a defining feature of APCs that process and present antigens to T cells. Hence, all antigen-presenting cells help in activation of T cells.
Thus, the correct answer is option (b).
