IB Bio HL Test: Human Health & Physiology III

What is the correct sequence of events during the phagocytosis of a bacterium by a leucocyte? I. Food vacuole forms II. Plasma membrane receptors detect antigen on the surface of the bacterium III. Lysosomes fuse with the food vacuole IV. Engulfs bacterium

II > IV > I > III

The following events occur when a mammalian immune system first encounters a pathogen. Place them in correct sequence and then choose the answer that indicates that sequence. I. Pathogen is destroyed. II. Lymphocytes secrete antibodies. III. Antigenic determinants (epitopes) from pathogen bind to antigen receptors on lymphocytes. IV. Lymphocytes specific to antigenic determinants from pathogen become numerous. V. Only memory cells remain.

III > IV > II > I > V

The following events occur when a mammalian immune system first encounters a pathogen. Place them in correct sequence and then choose the answer that indicates that sequence. I. Pathogen is destroyed. II. Lymphocytes secrete antibodies. III. Antigenic determinants from pathogen bind to antigen receptors on lymphocytes. IV. Lymphocytes specific to antigenic determinants from pathogen become numerous. V. Only memory cells remain.

III > IV > II > I > V

When a pathogen is ingested by a phagocyte, which event occurs first? a. Antigen presentation by the phagocyte b. B-cell activation c. T-cell activation d. Memory cell proliferation

a. Antigen presentation by the phagocyte

Where is human chorionic gonadotrophin (HCG) produced? a. Embryo b. Ovary c. Anterior pituitary d. Posterior pituitary

a. Embryo

Which action below is affected by an antihistamine? a. blood vessel dilation b. phagocytosis of antigens c. MHC presentation by macrophages d. the secondary immune response e. clonal selection by antigens

a. blood vessel dilation

Which cell type interacts with both the humoral and cell-mediated immune pathways? a. helper T cells b. plasma cells c. natural killer cells d. cytotoxic T cells e. CD8 cells

a. helper T cells

Which of these improperly pairs an endocrine gland and a hormone it secretes? a. ovary-follicle stimulating hormone b. pancreas-insulin c. pineal gland-melatonin d. thyroid-thyroxine

a. ovary-follicle stimulating hormone

Fertilization of human eggs usually takes place in the: a. oviduct/Fallopian tube. b. ovary. c. vagina. d. labia minora. e. uterus.

a. oviduct/Fallopian tube

In the inflammatory response, the absence of which of the following would prevent all the others from happening? a. release of histamine b. dilation of arterioles c. increased permeability of blood vessels d. leakage of plasma to the affected area e. increased population of phagocytes in the area

a. release of histamine

What name is given to the molecules that bind to foreign proteins that enter the body? a. Antigens b. Antibodies c. Allergens d. Antibiotics

b. Antibodies

What happens when beta cells of the pancreas release insulin into the blood? a. Blood glucose levels rise to a set point and stimulate glucagon release. b. Body cells take up more glucose. c. The liver breaks down glycogen to glucose. d. Alpha cells are stimulated to release glucose into the blood. e. Both B and D are correct.

b. Body cells take up more glucose.

Which of the following is an effect of HIV on the human body? a. It reduces the number of erythrocytes in the blood b. It reduces the number of lymphocytes in the blood c. It increases the amount of plasma in the blood d. It reduces the number of platelets in the blood

b. It reduces the number of lymphocytes in the blood

Which of the following is a function of the acrosome contents during fertilization? a. trigger the completion of meiosis by the sperm cell. b. digest the exterior coats (zona pelucida) of the egg. c. help propel the sperm toward the egg. d. nourish the mitochondria of the sperm. e. block polyspermy.

b. digest the exterior coats (zona pelucida) of the egg.

These cells are involved in innate immunity, and a person lacking these cells may have a higher than normal chance of developing malignant tumors. a. cytotoxic T cells b. natural killer cells c. helper T cells d. macrophages e. B cells

b. natural killer cells

Which cells are diploid? a. spermatids b. spermatogonia c. mature sperm cells d. A and B only e. A, B, and C

b. spermatogonia

Which of the following is a false statement about innate immunity? a. They include inflammatory responses. b. They include physical and chemical barriers. c. They must be primed by the presence of antigen. d. They may involve the formation of membrane attack complexes. e. Macrophages and natural killer cells are participants in the process.

c. They must be primed by the presence of antigen.

Why do antibiotics kill bacteria but not viruses? a. Viruses have a way of blocking antibiotics. b. Viruses are too small to be affected by antibiotics. c. Viruses do not have a metabolism. d. Antibiotics stimulate the immune system against bacteria but not viruses.

c. Viruses do not have a metabolism.

The clonal selection theory is an explanation for how a. a single type of stem cell can produce both red blood cells and white blood cells. b. V gene and J gene segments are rearranged. c. an antigen can provoke development of very few cells to result in production of high levels of specific antibodies. d. HIV can disrupt the immune system. e. macrophages can recognize specific T cells and B cells.

c. an antigen can provoke development of very few cells to result in production of high levels of specific antibodies.

Which of the following is the last line of defense against an extracellular pathogen? a. lysozyme production b. phagocytosis by neutrophils c. antibody production by plasma cells d. histamine release by basophils e. lysis by natural killer cells

c. antibody production by plasma cells

The clonal selection theory implies that: a. brothers and sisters have similar immune responses. b. only certain cells can produce interferon. c. antigens activate specific lymphocytes. d. a B cell has multiple types of antigen receptors. e. the body selects which antigens it will respond to.

c. antigens activate specific lymphocytes

What are antigens? a. proteins that consist of two light and two heavy polypeptide chains b. proteins released during an inflammatory response c. foreign molecules that trigger the generation of antibodies d. proteins found in the blood that cause foreign blood cells to clump e. proteins embedded in B cell membranes

c. foreign molecules that trigger the generation of antibodies

If the release of LH were inhibited in a human female, which of the following events would not occur? a. production of estrogen by follicle cells b. release of FSH from the pituitary c. ovulation of a secondary oocyte d. maturation of a primary follicle and oocyte e. release of GnRH from the hypothalamus

c. ovulation of a secondary oocyte

Phagocytosis of microbes by macrophages is enhanced by a. the binding of antibodies to the surface of microbes. b. antibody-mediated agglutination of microbes. c. the release of cytokines by activated B cells. d. A and B only e. A, B, and C

d. A and B only

Monoclonal antibodies are produced by hybridoma cells. Hybridoma cells are formed by fusing tumor cells with another cell type. What is this cell type? a. Phagocytes b. T-cells c. Stem cells d. B-cells

d. B-cells

Which of the following is true of both T cells and B cells? a. They produce effector cells against specific pathogens. b. They are produced from stem cells of the bone marrow. c. They can attack and destroy invading pathogens. d. Only A and B are true. e. A, B, and C are true.

d. Only A and B are true.

What are antigens? a. proteins found in the blood that cause foreign blood cells to clump b. proteins embedded in B cell membranes c. proteins that consist of two light and two heavy polypeptide chains d. foreign molecules that trigger the generation of antibodies e. proteins released during an inflammatory response

d. foreign molecules that trigger the generation of antibodies

Which cell and signaling molecule are responsible for initiating an immune response? a. phagocytes: lysozyme b. phagocytes: chemokines c. dendritic cells: interferon d. mast cells: histamine e. lymphocytes: interferon

d. mast cells: histamine

In vertebrate animals, spermatogenesis and oogenesis differ, in that: a. oogenesis produces four haploid cells, whereas spermatogenesis produces only one functional spermatozoon. b. spermatogenesis begins before birth. c. oogenesis begins at the onset of sexual maturity. d. oogenesis produces one functional ovum, whereas spermatogenesis produces four functional spermatozoa.

d. oogenesis produces one functional ovum, whereas spermatogenesis produces four functional spermatozoa.

Naturally acquired passive immunity would involve the: a. ingestion of interferon. b. absorption of pathogens through mucous membranes. c. injection of antibodies. d. placental transfer of antibodies. e. injection of a vaccine.

d. placental transfer of antibodies.

What would happen if a woman in the later stages of pregnancy were given a combination of estrogen and oxytocin? a. Oxytocin would bind to receptors on uterine smooth muscle cells. b. Prostaglandins would be secreted from the placenta and uterus. c. Contractions of uterine muscles would begin. d. A and C only e. A, B, and C

e. A, B, and C

Physical barriers to invasion by other organisms: a. include the skin and the mucous membranes. b. are difficult for bacteria and viruses to penetrate. c. may work in conjunction with secretions like tears, perspiration, and mucus. d. Only A and C are correct. e. A, B, and C are correct.

e. A, B, and C are correct.

Only certain cells in the body are target cells for the steroid hormone aldosterone. Which of the following is the best explanation for why these are the only cells that respond to this hormone? a. Nontarget cells destroy aldosterone before it can produce its effect. b. Only target cells are exposed to aldosterone. c. Aldosterone is unable to enter nontarget cells. d. Nontarget cells convert aldosterone to a hormone to which they do respond. e. Only target cells contain receptors for aldosterone.

e. Only target cells contain receptors for aldosterone.

Blood samples taken from an individual who had been fasting for 24 hours would have which of the following? a. high levels of insulin b. high levels of glucagon c. low levels of insulin d. low levels of glucagon e. both B and C

e. both B and C

A major difference between active and passive immunity is that active immunity requires: a. proliferation of lymphocytes in bone marrow. b. acquisition and activation of antibodies. c. secretion of interleukins from macrophages. d. transfer of antibodies from the mother across the placenta. e. direct exposure to a living or simulated pathogen.

e. direct exposure to a living or simulated pathogen.

Which of the following cell types are responsible for initiating a secondary immune response? a. macrophages b. T cells c. B cells d. stem cells e. memory cells

e. memory cells

When antibodies attack antigens, clumping of the affected cells generally occurs. This is best explained by: a. denaturation of the antibodies. b. disulfide bridges between the antigens. c. complement that makes the affected cells sticky. d. bonds between class I and class II MHC molecules. e. the shape of the antibody with at least two binding regions.

e. the shape of the antibody with at least two binding regions.