ATI TEAS Science

Which of the following describes the immune system mistakenly recognizing harmless foreign particles as serious threats?

ALLERGY When the immune system mistakenly recognizes harmless foreign particles as serious threats, the response is termed an allergy. Allergies are manifested when the immune system mistakenly recognizes harmless foreign particles as serious threats. Allergies launch an immune response, which causes sneezing, runny nose, and watery eyes. Antihistamines block the effects of histamines and bring relief to allergy sufferers. Humoral immunity is also called antibody-mediated immunity, meaning that it is controlled by antibodies. The efforts of the white blood cells known as phagocytes and T-cells are called the cell-mediated immune system. When B-cells and T-cells are activated by a pathogen, memory B-cells and T-cells develop, and the primary immune response results, it is called active immunity. Passive immunity is the transfer of active immunity, in the form of ready-made antibodies, from one individual to another, i.e., mother to child.

Which of the following proteins in the blood can destroy pathogens?

COMPLEMENT SYSTEM The complement system enhances the ability of antibodies and phagocytic cells to clear pathogens. It consists of a number of proteins synthesized by the liver that act for the complement activation cascade, which leads to a massive amplification of the response and activation of the cell-killing membrane attack complex. The major histocompatibility complex attaches itself to pathogens for faster recognition by the appropriate T-cells. Fibrinogen and platelets are both involved in the blood coagulation process.

Which of the following constitute the regional groups of lymph nodes?

Explanation Parotid lymph nodes, submandibular lymph nodes, and submental lymph nodes are a few groups of regional lymph nodes in the head and neck. Parotid lymph nodes get lymph from the portion of scalp above the parotid salivary glands, from the anterior wall of the external auditory meatus, some parts of eyelids, and the middle ear. Submandibular lymph nodes get their lymph from the front portion of the scalp, nose, cheeks, lips, paranasal sinuses, teeth, anterior part of the tongue, floor of the mouth, and gums. Submental lymph nodes receive lymph from the tongue, floor of the mouth, teeth, gums, and skin of the chin. All these regional groups of lymph nodes drain into the deep cervical lymph nodes.

Which of the following cells are known as phagocytes?

Explanation Phag/o = eat, swallow; cyte/o = cell The white blood cells (WBCs) are responsible for eating foreign particles by engulfing them. This process is known as phagocytosis, and the cells are termed as phagocytes. Once engulfed, the phagocyte breaks the foreign particles apart in organelles called lysosomes. WBCs normally circulate throughout the blood, but will enter the body's tissues if invaders are detected. Red blood cells and platelets are not involved in the process of phagocytosis. Red blood cells function to carry out oxygenation of blood while platelets that are involved in clot formation.

Which of the following is not part of the inflammatory response of the immune system?

Explanation When pyrogens are released, the temperature rises. The inflammatory response is considered the second line of defense. Injured body cells release chemicals called histamines, which begin the inflammatory response: Capillaries dilate. Pyrogens are released and reach the hypothalamus, and body temperature rises. Pain receptors activate. White blood cells flock to the infected area like sharks to blood.

Which of the following immunities is provided by the secretion of antibodies by B-cells?

HUMORAL Immunity is the ability of the body to resist infection by invading pathogens. The body has two main types of immunity: innate and acquired. This is further defined by the functions of cells within the immune system: active and passive. Humoral immunity is provided by B-lymphocytes, which reside in body tissues, search for invading antigens, and label them for destruction. Humoral immunity is a subtype of acquired, active immunity. Innate (or natural) immunity is not acquired from another source. It comes from white blood cells produced by the body, including natural killer cells and phagocytes, which can respond immediately to invading antigens and attack without specifically recognizing the invader. Phagocytosis is the process by which innate immune cells attack and destroy antigens. It is part of innate immunity. Cell-mediated immunity involves T-lymphocytes specifically. They attack and destroy cells directly. Secretion of antibodies provides permanent immunity. The next time the same pathogen attacks an individual, the antibodies previously secreted will recognize the antigen of the pathogen and destroy it immediately. This is called acquired immunity, because the body's B- and T-cells must learn to recognize the antigen, and the response is specific to that antigen. Passive immunity results from getting actual antibodies (immunoglobulin) to protect the body. This can occur in a few ways. Passive immunity may be accomplished by receiving immunoglobulin donated by others or by transfer of antibodies or lymphocytes from one individual to another. A mother can pass antibodies to her baby.

Which of the following blood types can be safely given to an individual with blood type B?

Individuals with blood type B are born with the anti-A antibody in their blood. Consequently, when blood from a type-A person is administered to individuals with blood type B, this triggers an immune response inside the body to destroy the cells containing antigens for A. Therefore, individuals with blood type B should receive donated blood from individuals with a compatible blood type—either B or O. Those with type A should receive blood from individuals who have blood types of either A or O. Persons with blood type O are the "universal donors" because they do not have antigens for A and B, so their blood can be given to individuals with any blood type. However, type-O individuals can only accept type-O blood products, because they have both type-A and type-B antibodies. People born with type AB blood are considered "universal recipients," as they do not have antibodies for either A or B. They can accept blood of any type.

Which of the following cells is non-phagocytic?

Lymphocytes are types of white blood cells that have antibodies that bind to specific antigens in the pathogen. They then release toxic enzymes to kill the pathogen. On the other hand, phagocytes are white blood cells that directly engulf pathogens and destroy them. Eosinophils, neutrophils, and monocytes are types of white blood cells that are phagocytic.

Which of the following types of white blood cells engulf and digest pathogens as their immune response?

The immune system produces different kinds of cells involved in different types of immune response: Macrophages are white blood cells that engulf and digest foreign substances and cellular debris, cancer cells, etc., that do not have the specific proteins present in a healthy body. They act in response to infection and accumulating damage or death of cells. B-cells are able to produce antibodies for certain antigens.\ T-cells assist the B-cells by secreting cytokines to mount a potent antibody response. Lymphocytes are capable of recognizing antigens.

Which of the following statements regarding macrophages is incorrect?

They are found abundantly in the blood. Macrophages are found in the organs, not in the blood. They are larger than neutrophils and are produced in bone marrow as monocytes. Monocytes are called macrophages once they reach the organs. Macrophages have long life spans. They initiate immune responses as they display antigens from the pathogens to the lymphocytes.