All AP Biology Resources
Example Questions
Example Question #11 : Immune System
Which leukocyte releases histamine in order to dilate blood vessels and increase blood flow to infected areas?
Plasma cells
Eosinophils
Basophils
Neutrophils
Basophils
Basophils are the least common leukocyte found in the body, but play a key role in the inflammatory response. They contain histamine, which is a potent vasodilator. Upon release, histamine will increase blood flow to infected areas. Mast cells are another immune cell that is involved in histamine release, but are generally localized to various regions of the body rather than found in circulation.
Basophils, mast cells, eosinophils, and neutrophils are all considered granulocytes and are essential cells in the innate immune response. Plasma cells are differentiated B-lymphocytes that are responsible for mass-producing antibodies to a specific antigen.
Example Question #12 : Immune System
Which of the following is not a characteristic of B-cell receptors?
Upon further maturation, the B-cell receptor can become a secreted molecule
They consist of two identical heavy chains and two identical light chains
They consist of two polypeptide chains
They have transmembrane domains that anchor into the B-cell plasma membrane
They consist of two polypeptide chains
Each B-cell receptor is a Y-shape molecule that, upon maturation, can become a secretory form (an antibody). Each receptor is comprised of four polypeptide chains: two identical heavy chains and two identical light chains. The four chains are linked together by disulfide bridges. Both heavy and light chains consist of constant regions, as well as variable regions. The variable regions of each chain provide the specificity for antigen binding, which generates a signaling cascade within the B-cell.
Example Question #1 : Understanding Cell Types
In what way do eosinophils differ from other innate immune system cells?
They produce anti-inflammatory cytokines
They detect and eliminate infected host cells
They have low phagocytic activity
They secrete antibodies
They have low phagocytic activity
The granulocytes are responsible for numerous functions of innate immunity, from secreting histamine, to phagocytosis, to anti-inflammatory processes. These cells are the basophils, neutrophils, eosinophils, macrophages (monocytes), and mast cells.
Eosinophils have a more limited role in innate defense than the other granulocytes. They possess only low phagocytic activity, however, they are more specialized to respond to multi-cellular pathogens, such as parasitic worms. Rather than phagocytosing an invading organism, eosinophils function by releasing an arsenal of destructive enzymes and free radicals to ward off the organism. The other granulocytes are specialized for phagocytosis of bacteria, viruses, and cellular debris.
Example Question #2 : Understanding Cell Types
Embryonic stem cells can go on to form any of the three germ layers (endoderm, mesoderm and ectoderm). How can they be defined?
Multipotent
Pluripotent
None of the other answers
Totipotent
Progenitor cells
Pluripotent
The ability to form any of the three germ layers is known as pluripotency. Totipotent cells, such as the zygote, are able to form an entire organism, multipotent cells are able to form any cell within the same germ layer lineage, and progenitor cells are cells closer to differentiation, often found in adult organisms.
Example Question #3 : Understanding Cell Types
What type of cell creates free antibodies that then circulate in the bloodstream?
Memory B-cells
Helper T-cells
Plasma cells
Cytotoxic T-cells
Monocytes
Plasma cells
Humoral, or B-cell, immunity is associated with the formation of antibodies. Plasma cells are B-lymphocytes that have been differentiated with the help of a helper T-cell. They release antibodies, which are created to respond to a specific pathogen in the body.
Cytotoxic T-cells are also activates by help T-cells, but are involved in cell-mediated immunity rather than humoral immunity. They target infected cells based on antibody tagging. Monocytes are a part of the innate immune response and are not involved in antibody interactions. They primarily differentiate into macrophages, which engage in phagocytosis of pathogens.
Example Question #4 : Understanding Cell Types
Which of the following cells is exclusive to the adaptive immune system?
Dendritic cells
Neutrophils
B-cells
Mast cells
Macrophages
B-cells
The adaptive immune system primarily relies on the function of B-cells and T-cells. T-cells help recognize antigens to which the body has been previously exposed and stimulate B-cell to release antibodies to combat that specific antigen.
Upon initial antigen exposure, all other cell types listed (which help comprise the innate immune system) kick in.
Example Question #17 : Immune System
Which immune cells primarily contribute to allergic reactions?
Mast cells
B-cells
Dendritic cells
T-cells
Phagocytes
Mast cells
Mast cells contains secretory granules, rich in histamine and other hormonal mediators, that promote inflammation and other allergy symptoms in response to antigen exposure.
Example Question #5 : Understanding Cell Types
Which immune cells contribute most to the humoral immune response?
Natural killer T cells
B cells
Helper T cells
Phagocytes
Basophils
B cells
The humoral response refers to the antiquated term "humors", meaning body fluids, as used in ancient and medieval medicine. In response to antigen exposure, B-cells release antibodies into the extracellular fluid and throughout the body, thus eliciting a "humoral response."
Although helper T-cells are responsible for activating B-cells, the humoral response is limited to B-cells because they are the ones releasing products into the body fluids.
Example Question #6 : Understanding Cell Types
Metastasis is __________.
the asexual reproduction of cells
the spread of the cells produced during mitosis
the spread of cancer cells beyond their site of origin
the spread of the cells produced during meiosis
the spread of cancer cells beyond their site of origin
Metastasis is the proliferation of cancer cells into new tissues. Cancer usually metastasizes through the circulatory or lymphatic systems, and the cancerous cells take residence in other, seemingly unrelated parts of the body.
Example Question #7 : Understanding Cell Types
Long-lived B cells that circulate the body and respond to subsequent infections are called __________.
Memory cells
Plasma cells
IgG
Immunoglobulins
Macrophages
Memory cells
Memory B cells circulate the body and are ready to respond to subsequent infections while plasma cells generate many antibodies to a current infect. "Immunoglobulins" refers to both the B cell receptor and to the excreted form of these proteins (known as antibodies). IgG is a class of immunoglobulins (along with IgA, IgE, IgD, and IgM). Finally, macrophages are cells that engulf non-self (and often antibody-bound) cells and communicate with T cells to promote B cell proliferation.