BME Test 3

An antigen is a unique structure. It is a substance that can induce an immune response when introduced into an immunocompetent host and that can react with the antibody produced from that response. It consists of epitopes recurring molecular groups in large molecules such as proteins, polysaccharides.

True

Innate immunity is the ability to resist damaging organisms and toxins. It involves the skin, gastric acids, tissue neutrophils and macrophages, and the complement system

True

One neutrophil can engulf 3-20 bacteria whereas one macrophage can engulf ~100 bacteria.

True

Opsonization is the process by which a foreign particle is marked for ingestion by a phagocyte. Opsonization involves the binding of an opsonin onto the particle. Most phagocytic binding cannot occur without opsonization. After opsonin binds to the membrane, phagocytes are attracted. The Fab portion of the antibody binds to the antigen, whereas the Fc portion of the antibody binds to an Fc receptor on the phagocyte, facilitating phagocytosis. The receptor-opsonin complex can also create byproducts like C3b and C4b which are important components of the complement system. These components are deposited on the surface of the particle and aid in its destruction.

True

Regarding acquired immunity: Dormant lymphocytes → Invasion of body by foreign antigen → Phagocytosis by macrophages → Presentation of antigen to lymphocytes which binds on surface antibodies (B-cell) or surface receptor protein (T-cell) → activation of T and B-cells

True

In a normal, healthy person, which of the following blood components typically has the longest life span?

macrophages

Where in the body are antigens typically presented for activation of the adaptive arm of the immune system?

nearest draining lymph node

Hormones can be

peptide and protein hormones steroid hormones amine hormones

If a patient has type AB blood, which of the following blood types can they receive? There more be more than one correct answer.

AB, OO

During an inflammatory response, which is the correct order for cellular events?

Activation of tissue macrophage, infiltration of neutrophils from the blood, infiltration of monocytes from blood, increased production of neutrophils and monocytes

Which of the following would be expected after an increase in hormone binding to plasma proteins?

An increase in the plasma reservoir for rapid replenishment of free hormone

What are the professional antigen-presenting cells (APCs) of the body?

Dendritic cells

A 20-year-old man presents to the emergency department with a 2-week history of diarrhea after a trip out of the country. He is admitted to the hospital for dehydration. His stool specimen is positive for parasitic eggs. Which type of white blood cells would have elevated numbers?

Eosinophils

Acquired immunity is non-specific and involves blood-circulating macrophages, platelets and occasionally B lymphocytes

False

Innate immunity is 100,000 times more potent than acquired immunity

False

Pluripotent hematopoietic stem cells are only committed to lymphoid stem cells

False

Which of the following is true regarding white blood cells?

Granulocytes are normally formed only in the bone marrow

Which of the following statement(s) about the nose is correct?

Most of the heat and humidity adjustment needed can be done via the nose The nose serves as a resonating chamber for speech The nose houses the olfactory receptors which are responsible for smelling The nose partially filters the inspired air and cleans it of foreign matter

Which of the following is true regarding phagocytic cells?

Neutrophils are active in the blood; non-dividing; short-lived (<8 hours in blood, ~5 days in tissue); dominant number in bloodstream Monocytes/Macrophages are active in the tissue; long-lived cells (10-20 hours in blood, months in tissue)

Some cells secrete chemicals into the extracellular fluid that act on cells in the same tissue. Which of the following refer to this type of regulation?

Paracrine

Presentation of antigen to a B lymphocyte will result in

Production of antibodies

Which of the following statement(s) about your lungs is correct?

The area of your deep lungs is equivalent to the area of a tennis court. If you inhale large particles of dust, they will primarily deposit onto your throat. A large porous particle (20 μm) with very low density behaves aerodynamically as a small particle (4 μm) and therefore deposits into the deep lungs.

Which of the following statements about peptide or protein hormones is usually true?

They have receptors on the cell membrane.