Hemolytic transfusion reactions are caused by complement activation after a person expresses antibodies against the antigens found on the inappropriately donated blood. Hemolytic Disease of the Newborn (HDN) is due to maternal antibodies against the Rh factor crossing the placenta, binding to the baby’s red blood cells, and stimulating the baby’s own complement system to lyse its red blood cells. Monocytes are the precursor cells of tissue macrophages.

Although most leukocytes circulate through the blood, they usually leave the capillaries and function extravascularly (outside the vessels). Some types of leukocytes can live out in the tissue for several months, but others may live for only hours or days. Leukocytes can be distinguished from one another in stained tissue samples by the shape and size of the nucleus, the staining characterisitcs of the cytoplasm and the cytoplasmic inclusions, and the regularity of the cell border.

Diffusion result in the overall movement of particles from an area of high concentration to an area of low concentration down a concentration gradient. If there is a big concentration difference, diffusion will take place more rapidly than if there is only a small concentration difference. The difference in concentration is known as concentration difference.

Active transport requires the assistance of a type of protein called a carrier protein, using energy supplied by ATP. d.) – pinocytosis – Known as cell drinking fluid endocytosis, and bulk-phase pinocytosis, is a mode of endocytosis in which small particles are brought into the cell; forming an invagination, and then suspended ithin small vesicles. These pinocytotic vesicles fuse with lysosomes to hydrolyze the particles.

Injections containing antibodies are another. Sometimes travelers going abroad may be injected with gamma globulin, but this passive immunity last only about three months. Passive immunizations are used to protect people who have been exposed to infections or toxins, like snake venom or tetanus. Active immunity can occur naturally, when a pathogen invades the body, or artificially, like when we are given vaccinations containing disabled or killed pathogens. The body does require prior exposure to an antigen to develop an active immunity.

The Immune System Pioneers

Albumin, alpha globulin and beta globulin are responsible for the transport of hormone, enzymes, and respiratory gases, particularly carbondioxide. The alpha and beta globulins play an important role in the transport of metals in the blood.ROLE AS RESERVE PROTEIN.During the conditions like fasting, inadequate food intake, the plasma proteins are utilized by the body tissues. Because of this, the plasma proteins are called the reserve proteins. Helper T cells, (Th cells) are the “middlemen” of the adaptive immune system. Once activated, they divide rapidly and secrete small proteins called cytokines that regulate or “help” the immune response.

Anything that can trigger the immune response is called an antigen. An antigen can be a microbe such as a virus, or even a part of a microbe. Tissues of cells from another person also carry nonself markers and act as antigens. This explains why tissue transplants can be rejected.

  • Symptoms of the intestinal bacterial infenction vary depending on bacteria.
  • It is estimated that for the million or so antigens we encounter in our lifetime we have an equal number of specific lymphocytes for each possible antigen.
  • In active transport a special transport protein in the cell membrane picks up the useful particle on one side of the membrane.
  • They are about 1-25 mm in diameter.
  • There are 3 pairs of tonsils in a ring about the pharynx.
  • Third, damaged epithelial cells are replaced at a rapid rate.


In an anaphylactic reaction, massive release of histamine and other cytokines cause widespread vasodilation, circulatory collapse, and severe bronchoconstriction. Unless treated promptly, anaphylaxis can result in death. Protecting against microbes which exist inside of our body’s cells (intracellular bacteria and intracellular viruses). A portion of these activated T cells become memory T cells (Tm). These cells record the information about the foreign antigen so T cells can respond more quickly, and more strongly, if a second exposure occurs.

In addition, Brunner’s gland in duodenum secretes bicarbonate, which is also an alkaline. Lastly, pancreas secretes an alkaline juice that would also protect the duodenum from the gastric juices. a lymph vessel that carries a liquid fluid called lymph. Vitamins A, D, E and K can only move with packaged fats in to the lacteal. The stomach pummels the food with muscular walls produces the protease enzyme pepsin.

Edema is the swelling that forms when too much tissue fluid forms or not enough taken away. It can be caused by a variety of conditions such as allergic responses (too much vasodilation), starvation (lack of albumin in blood lowers osmotic pressure and decreases amount of fluid returning to capillaries), and lymphatic disorders (e.g. blockage due to parasite in elephantiasis, or removal of lymph nodes due to a radical mastectomy). Edema is common in the lower extremities when people spend a lot of time sitting, because the fluid return is based largely on the massaging action of skeletal muscles. C) A protein generated by the immune system in response to a foreign substance. 9-A foreign substance, usually a protein, that stimulates the immune system to react, such as by producing antibodies is a ______________.

We classify these into three broad categories; autoimmunity, immunodeficiencies, and hypersensitivities. 2. Upon reexposure, the body reacts more strongly and rapidly. The allergen binds to IgE already present on mast cells, triggering the immediate release of histamine, cytokines, and other mediators that cause allergic symptoms.

HIV is a retrovirus that primarily infects vital components of the human immune system such as CD4+ T cells (a subset of T cells), macrophages and dendritic cells. It directly and indirectly destroys CD4+ T cells.

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