Options are not provided in teh question. The complete question is as following:
Which of the following classes of antibodies is most likely to be made by the oldest plasma cell in a population of B cells?
a. IgM
b. IgG
c. IgA
d. None of the listed responses is correct.
Answer:
c. IgA
Explanation:
Specialized white blood cells called B lymphocytes (or B cells) contain antibodies. The mature B cells, or plasma cells, secrete millions of antibodies into the lymphatic system and the bloodstream. The plasma cell antibodies have the exact same antigen-binding site and specificity as the precursors to their B cells. Five different types of antibodies are present in humans: IgA, IgM, IgG, IgD,IgE.
In the oldest plasma cell igA classes of antobodies are present because initially plasma cells secret IgM but it switch and forms IgG, as the plasm aget older ans switch of antibodies takes place for scond time they can make IgA or IgE.
Hence, the correct option is c. IgA.
Answer:
Compounds are made of different types of atoms.
Elements cannot be broken down by physical or chemical changes
Elements are made of only one type of atom.
Explanation:
An Element is any one of the simplest chemical substances that CANNOT be decomposed in a chemical reaction or by any chemical means and made up of atoms all having the same number of protons. Examples are Sodium (Na), Nitrogen (N2), Aluminium (Al)
Compound is a substance formed by chemical union of two or more ingredients in definite proportions by weight. examples are NaCl (Sodium Chloride), NH3 (Ammonia)
Answer:
B
Explanation:
When your cells are lacking nutrients, it starts to take nutrients from your food and water.
Answer:
Respiration begins at the nose or mouth, where oxygenated air is brought in before moving down the pharynx, larynx, and the trachea. The trachea branches into two bronchi, each leading into a lung. Each bronchus divides into smaller bronchi, and again into even smaller tubes called bronchioles.
Answer:
It starts with a bend in a river then the river erodes the bend until it goes through the bend and the old bend keeps its water and becomes a lake