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| * A disease causing agent, such as a bacterium or virus, is called a(n) _____. | pathogen p743 |
| * The first lines of defense offered by immune systems help prevent pathogens from _____. | getting into the hosts body p.743 |
| * the two types of immune defense found among animals are ______ immunity, which is common to all animals, and _____ immunity, which is only found in vertebrates. | innate, adaptive p743 |
| ** TRUE or FALSE: Innate immunity is common to all animals. | TRUE p744 |
| ** TRUE or FALSE: Adaptive immunity is common to all animals. | FALSE (Adaptive immunity is only found in vertebrates) p744 |
| * The barrier defenses of mammals, which block the entry of many pathogens, include the _____ and the ___. | mucous membranes, skin. p745 |
| * In ______ immunity, which includes barrier defenses, molecular recognition relies on a small set of receptor proteins that bind to molecules or structures that are absent from animal bodies but common to a group of viruses, bacteria, or other pathogens. | innate p744 |
| * In _____ immunity, molecular recognition relies on a vast arsenal of receptors, each of which recognizes a feature typically found only on a particular part of a particular molecule in a particular pathogen. | adaptive p744 |
| * The adaptive immune response can also be called the ______ immune response. | acquired p744 |
| * The adaptive immune response is enhanced by _________ to the infecting pathogen. | previous exposure p744 |
| ** TRUE or FALSE: Innate immunity is also found in plants. | TRUE p744 |
| ** Within the digestive system of insects, _______, an enzyme that breaks down bacterial cell walls, acts as a chemical barrier against pathogens ingested with food. | lysozyme p744 |
| ** In insects, the major immune cells are called ____. | hemocytes p744 |
| * After an immune cell phagocytizes a pathogen, the vacuole that is formed around the pathogen will merge with a(n) ______ so that the pathogen can be broken down by digestive enzymes. | lysosome p744,  |
| * Some immune cells ingest pathogens through a process called _____. | phagocytosis p744, |
| ** _____, an enzyme found in tears, saliva, and mucous secretions destroys the cell walls of susceptible bacteria as they enter the openings around the eyes or the upper respiratory tract. | Lysozyme p745 |
| ** One way your body fights pathogens is to create acidic environments that kill the pathogens. What are two places where this occurs? | skin and stomach (Secretions from oil and sweat glands drop pH to the 3 to 5 range. The stomach has a pH that averages around 2) p745 |
| * The two main types of phagocytic cells in the mammalian body are _______ and ________. | Neutrophils, macrophages p745 |
| ** Eosinophils, often found in tissues underlying an epithelium, are important in defending against multicellular invaders, such as parasitic worms. Upon encountering such parasites, eosinophils discharge _______. | destructive enzymes p745 |
| ** _______ cells mainly populate tissues, such as skin, that contact the environment. They stimulate adaptive immunity against pathogens that they encounter and engulf. | Dendritic p745 |
| ** _________ cells circulate through the body and detect the abnormal array of surface proteins characteristic of some virus-infected and cancerous cells. These immune cells do not engulf stricken cells. Instead, they release chemicals that lead to cell death, inhibiting further spread of the virus or cancer | Natural killer cells p745 |
| ** Natural killer cells attack and destroy your own cells, but only if they _____. | are cancerous, or have been infected with a virus p745 |
| * The _______ system is a network of tissues and organs that help rid the body of toxins, waste and other unwanted materials. The primary function of this system is to transport lymph, a fluid containing infection-fighting white blood cells, throughout the body. | lymphatic 746,  |
| * Virus-infected body cells secrete ______ proteins that induce nearby uninfected cells to produce substances that inhibit viral replication. | interferon (Besides being produced by cells infected by virus, some white blood cells release a different type of interferon that attracts macrophages to come in a phagocytize the pathogen. Interferons are now being produced in the lab and injected into people to help boost their immune system) p.746 |
| * The _____ system consists of roughly 30 proteins in blood plasma. These proteins circulate in an inactive state and are activated by substances on the surface of many pathogens. Activation results in a cascade of biochemical reactions that can lead to lysis (bursting) of invading cells. This system also functions in the inflammatory response. | complement (Notice how these proteins self-assemble to produce a knife-like structure that punctures the targeted cell) p746,  |
| ** During an inflammatory response, Activated macrophages discharge ________ signaling molecules that recruit neutrophils to the site of injury or infection. | cytokine p746 |
| ** During an inflammatory response, Activated macrophages discharge cytokine signaling molecules that recruit _______ to the site of injury or infection. | neutrophils p746,  |
| ** During an inflammatory response, Activated ________ discharge cytokine signaling molecules that recruit neutrophils to the site of injury or infection. | macrophages, |
| * _______, immune cells found in connective tissue, release the signaling molecule histamine at sites of damage. Histamine causes a series of events that lead to ______. | Mast cells, inflammation (You've probably heard of anti-histamines. These are chemicals, often found in nasal spray, that block the effect of histamines and reduce inflammation) p746 |
| * One strategy of the inflammatory response is to induce a slight ____ in the animal. This is thought to make it more difficult for bacteria to reproduce, and it also might speed up phagocytosis and the chemical reactions necessary to fight off infection. | fever p747 |
| ** Certain bacterial infections can induce an overwhelming systemic inflammatory response, leading to a life-threatening condition called septic shock. Characterized by very high fever, low blood pressure, and poor blood flow through capillaries. | septic shock p747 |
| * The adaptive response relies on ____ and _____, which are types of white blood cells called _____. | T cells, B cells, lymphocytes p747,  |
| * Like all blood cells originate from stem cells in the ______. | bone marrow p747, |
| ** Lymphocytes that migrate to the thymus mature into ____ cells. | T p747, |
| ** Lymphocytes that migrate to the _____ mature into T cells. | thymus p747, |
| ** Lymphocytes that remain and mature in the bone marrow develop as ___ cells | B p747, |
| ** Lymphocytes that remain and mature in the ____ develop as B cells | bone marrow p747, |
| * Any substance that elicits a B or T cell response is called a(n) ____. | antigen p747,  |
| * The part of the T or B cell that binds to a part of a pathogen's outer surface is called a(n) _____. | antigen receptor (The diagram below shows antigen receptors for B and T cells) p747, |
| * A given lymphocytes antigen receptor can bind to ____ type of antigen. | only one (Yet your body has to recognize millions of different antigen shapes, so it produces millions of different types of antigen receptors. How does it do this. Each antigen receptor is made of protein and we only have about 20,000 different genes and most of them are not for antigen receptors. The answer is random combination of a couple different genes that code for the variable regions of antigen receptors early on in lymphocyte development with all the other genes being cut out and eliminated. The lymphocyte then makes a certain shaped antigen receptor for the rest of its life and passes that trait on when it divides. This random recombination allows there to be over a million B-cell antigen receptors and 10 million different T-cell receptors) p749,  |
| * The small part of an antigen that an antigen receptor can actually bind to is called the _____. | epitope p747,  |
| * Each B cell antigen receptor is a(n) ___ shaped protein | Y, |
| * Binding of a B cell antigen receptor to an antigen is an early step in B cell activation, leading eventually to formation of cells that can release these Y-shaped antigen receptors into blood or lymph. The Y-shaped antigen receptors that are no longer attached to a cell are called ____ or _____. | antibodies, immunoglobulins p748,  |
* Which type of lymphocyte is shown below?,  | B-cell p747, |
* Which type of lymphocyte is shown below?,  | T-cell p747, |
| * What do histamines do to blood vessels? | Causes them to dialate and become more permeable (This increases the amount of blood plus white-blood cell and immune protein-rich fluids that go to the site of an injury. This is the purpose of inflammation) p746 |
| ** Antigen receptors of T-cells must wait for one of your own cells to present an antigen fragment from a pathogen that got into the host cell. These antigens are presented by a host protein called _____.d by | the major histocompatibility complex (MHC) molecule p748,  |
| ** When infected cells or phagocytic immune cells display a fragment on its cell surface via an MHC molecule, the process is called _____. | antigen presentation (This allows T cells to recognize pathogens and also viral infected cells that need to be destroyed) p749 |
| * Lymphocytes that happen to develop antigen receptors that bind to your own body cell antigens are eliminated or inactivated after being tested for self-reactivity while they are being formed in the bone marrow. This ensures the concept of ______. | self-tolerance p750 |
| * What happens immediately after a B or T cell is activated by having its antigen receptor bind to an epitope from a pathogen. | The lymphocyte will start dividing over and over again (This allows an immune response to develop. Some of the new cells will turn into short-lived effector cells that fight the infection while others will turn into long-lived memory cells that will allow for much quicker recognition and immune response initiation if the infection re-occurs in the future) p750 |
| * Once a lymphocyte is activated (by binding to an antigen), it will divide over and over again. Some of these cells become ____ cells that are short-lived and fight the infection. The rest become long-lived _____ cells that stay in the body and help make recognition of the same pathogen quicker in the future if re-infection were to occur. | effector, memory p750 |
| * What do you call B cell effector cells? | Plasma cells (These are cells that are capable of secreting antibodies into blood and lymph),  |
| * Which type of cells, once activated, can become plasma cells that secrete antibodies? | B cells p750, |
| * What do plasma cells do? | secrete antibodies into the blood or lymph (Remember, these are the effector cells that B cells turn into once they've bumped into a pathogen. B cells will also develop into memory cells) p750, |
| ** The proliferation of a certain type of lymphocyte after binding to an antigen is called ____. | clonal selection p750, |
| ** What are the two types of effector cells that can develop from activated T cells? | helper T cells and cytotoxic T cells p750 |
| ** A primary immune response peaks about ___ to ___ days after the initial exposure. | 10 to 17 p751,  |
| ** A secondary immune response peaks about ___ to ___ days after the initial exposure. | 2 to 7 p751, |
| * The ______________ immune response protects the blood and lymph by using antibodies to neutralize or eliminate toxins or pathogens in the body fluids. | humoral p752 |
| * The humoral immune response protects the blood and lymph by using ______ to neutralize or eliminate toxins or pathogens in the body fluids. | antibodies p752 |
| * The _____ immune response uses specialized T cells to destroy infected host cells. | cell-mediated p752 |
| * The cell-mediated immune response uses specialized T cells to destroy _____. | infected host cells p752 |
| ** Which type of cell, once activated, stimulates both humoral and cell-mediated immune responses? | helper T-cells p753,  |
| * TRUE or FALSE: Only immune cells can display foreign antigens on their surface. | FALSE (Both immune cells and infected body cells can display antigens on their surface that help activate T cells) p752 |
| ** Each plasma cell secretes approximately ____ antibodies every second during its four- to five-day life span. | 2,000 (That amounts to about a trillion antibodies secreted per plasma cell during its lifecycle) p752 |
| * The targeted destruction of an infected host cell by a cytotoxic T cell involves the secretion of proteins that disrupt ______ integrity and trigger cell death | membrane p.754 |
| * The targeted destruction of an infected host cell by a(n) ____ cell involves the secretion of proteins that disrupt membrane integrity and trigger cell death | cytotoxic T p754 |
| ** Cytotoxic T cells will release _____ molecules which form pores in the infected cell, and also _____, which are enzymes that break down proteins and initiate apoptosis (programmed cell death) in the infected cell. | perforin, granzymes p754,  |
| * _____ is a process that involves the use of antigens artificially introduced into the body to generate an adaptive immune response and memory cell formation. | Immunization p754 |
| * A(n) _______ is a collection of harmless epitopes that are introduced into the body to immunize a person against infection by a real pathogen. | vaccine (vaccines today can be made from inactivated bacterial toxins, killed or weakened pathogens, or even genes encoding microbial proteins) p754 |
| * When antibodies in the blood of a pregnant female cross the placenta to her fetus, this type of protection is called _______ immunity because the antibodies in the recipient (in this case, the fetus) are produced by another individual (the mother) | passive p756 |
| * If you get bitten by a venomous snake and received a dose of antivenin, what your are really getting are _____ that were harvested from the blood of an animal that was vaccinated against the snakes venom. | antibodies p756 |
| * ______ are exaggerated (hypersensitive) responses to certain harmless antigens. | Allergies p757 |
| ** A person may die from a severe allergic reaction by going into ______. | anaphylactic shock (Inflammatory chemicals released from immune cells trigger constriction of bronchioles and sudden dilation of peripheral blood vessels, which causes a precipitous drop in blood pressure. Death may occur within minutes due to the inability to breathe and lack of blood flow) p757 |
| ** A person who is having a severe allergic reaction (for instance, to a bee sting) and is in danger of going into anaphylactic shock, can be given a shot of ____ which counteracts the allergic response. | epinephrine p757 |
| * When a person's own immune system attacks certain cells or natural proteins in their body, they are said to have a type of ______ disease. | autoimmune (In systemic lupus erythematosus, or lupus, the immune system generates antibodies against histones and DNA. Autoimmunity can also target the insulin-producing beta cells of the pancreas (in type 1 diabetes) and the myelin sheaths that encase many neurons (in multiple sclerosis) p757 |
| ** The changing of cell surface proteins (epitopes) by a pathogen through mutation or some other means is called _____. | antigenic variance (this is what makes it hard to have long-lasting immunity to influenza, even if you've been previously exposed, because the virus changes it's surface epitopes often) p758 |
| ** Some viruses avoid an immune response by infecting cells and then entering a largely inactive state called ____. | latency (In latency, the production of most viral proteins and free viruses ceases; as a result, latent viruses do not trigger an adaptive immune response. Latency typically persists until conditions arise that are favorable for viral transmission or unfavorable for host survival. Herpes and HPV, the human papillomavirus, are examples of viruses that might not cause symptoms for years after the actual infection event) p758 |
| ** The human immunodeficiency virus (HIV) attacks cells of your adaptive immune response, specifically, _____ cells. | helper T p759 |
| * The human immunodeficiency virus (HIV) can lead to ____ which stands for ____. This leads to the immune system not being able to fight off secondary infections and cancers that are normally handled by healthy immune systems. | AIDS, acquired immune deficiency syndrome p759 |
| ** ______ are involved in about 15–20% of all human cancers. | Viruses (Because the immune system can recognize viral proteins as foreign, it can act as a defense against viruses that can cause cancer and against cancer cells that harbor viruses) p759 |
| * Which virus can cause cervical cancer? | HPV (This virus, known as the human papillomavirus, is easily spread through sexual contact and can remain latent for years before causing symptoms, most often cervical cancer in females or genital warts in both males and females. It is estimated that over half the human population born before the early 1990's has some form of HPV. This can now be prevented through vaccination as long as it's done at an early age) p759 |
