Question

question 1 (1 point) saved
antigen presenting cells include
macrophages, b cells, dendritic cells
t cells, b cells, mast cells
memory cells, macrophages, tc cells
plasma cells, mast cells, immunoglobulin cells
question 2 (1 point) saved
this immunoglobulin gives long - term immunity and is associated with memory response.
igg
iga
igm
igd
question 3 (1 point) saved
a titer is the concentration of
a ntigen in plasma.
antibody in serum.
a ntigen in serum.
antibody in whole blood.

Explanation:

• Question 1: Antigen - presenting cells (APCs) are cells that can present antigen to T - cells. Macrophages, B cells, and dendritic cells are well - known APCs. T cells are mainly involved in cell - mediated immunity, mast cells are related to allergic reactions, memory cells are for immune memory, \(T_C\) (cytotoxic T cells) kill infected cells, plasma cells secrete antibodies, and immunoglobulin is a protein (not a cell type).
• Question 2: IgG is the most abundant immunoglobulin in the blood. It can cross the placenta (in pregnant women) and provides long - term immunity. IgA is mainly in mucosal secretions, IgM is the first - line defense in the initial immune response, and IgD has a less - clear function in immunity.
• Question 3: A titer is a measure of the concentration of antibodies in serum. Serum is the liquid part of blood after clotting (without fibrinogen and blood cells). Plasma is the liquid part of blood (with fibrinogen), and whole blood contains cells. Antigens are usually measured in other ways rather than by titer.

Answer:

• Question 1: macrophages, B cells, dendritic cells
• Question 2: IgG
• Question 3: antibody in serum