36. ______ do NOT depend on the circulatory system to deliver oxygen to the tissues.
(A)Insects
(B)Molluscs
(C)Mammals
(D)Birds
(E)Amphibians

32. Our sense of balance depends most directly on (A)the vestibular system. (B)the auditory system. (C)the visual system. (D)mechanoreceptors in our hands and feet. (E)stretch receptors in our skeletal muscles.

33. Bile is crucial for ______ digestion because of its function in _______. (A)protein, protecting the stomach lining (B)fat, solubilizing glycerol:fatty acid bonds (C)nucleic acids, uncoiling DNA strands (D)fat, emulsification (E)protein, lyophilization

34. Which of the following bacteria is known to be a contributing factor in the development of stomach ulcers? (A)Clostridium tetani (B)Vibrio cholerae (C)Helicobacter pylori (D)Staphylococcus aureus (E)Escherichia coli

35. Estivation in animals is an example of what specific phenomenon? (A)sleep (B)rest (C)torpor (D)hiding (E)activity

37. The volume of air normally breathed in and out of the lungs in a single breath at rest is referred to as the _____ volume. (A)tidal (B)total (C)reserve (D)inspiratory reserve (E)expiratory reserve

38. The bulk of the reabsorption of useful materials by the kidney takes place in the (A)renal corpuscle. (B)proximal convoluted tubule. (C)loop of Henle. (D)distal convoluted tubule. (E)collecting ducts.

39. The descending portion of the loop of Henle is (A)permeable to water and impermeable to sodium. (B)permeable to water and permeable to sodium. (C)impermeable to water and permeable to sodium. (D)impermeable to water and impermeable to sodium. (E)the site of active transport of water

40. ________ is a water-soluble hormone derived from the nervous system that regulates blood volume and blood pressure? (A)Antidiuretic hormone (B)Aldosterone (C)Cortisol (D)Oxytocin (E)Adrenocorticotropic hormone

41. The ectoderm is to the central nervous system as the mesoderm is to the (A)epidermis. (B)respiratory tube. (C)digestive tract. (D)skeletal muscle. (E)peripheral nervous system. 

42. The clonal selection theory is an explanation for (A)how a single type of stem cell can produce both red blood cells and white blood cells. (B)how antibody proteins can be molded to fit antigens after the antigen interacts with the antibody-producing type of cell. (C)how an antigen can induce the multiplication of very few cells to result in production of high levels of specific antibodies. (D)how HIV can disrupt the immune system. (E)how macrophages can recognize specific T cells and B cells.