Select the correct statement about oxygen transport in blood: a. during conditions of acidosis, hemoglobin is able to carry oxygen more efficiently. b. during normal activity, a molecule of hemoglobin returning to the lungs carries one molecule of o2. c. a 50% oxygen saturation level of blood returning to the lungs might indicate an activity level higher than normal. d. increased bpg levels in the red blood cells enhance oxygen-carrying capacity.

Which of these is a sexual stereotype? a) on average, males are taller than females. b) people over the age of 60 are not interested in sex. c) male hormone levels differ from those of females. d) there are more male representatives than female representatives in congress.

Which of the following defines scoliosis? a. a posture disorder characterized by the shoulders being rounded and the back hunched b. a posture disorder in which the spine curves up the back like a snake c. a posture disorder characterized by excessive curvature or arch in the lower back d. none of the above

What is the main structural difference between enveloped and nonenveloped viruses? a) enveloped viruses have their genetic material enclosed by a layer made only of protein.b) nonenveloped viruses have only a phospholipid membrane, while enveloped viruses have two membranes, the other one being a protein capsid.c) enveloped viruses have a phospholipid membrane outside their capsid, whereas nonenveloped viruses do not have a phospholipid membrane.d) both types of viruses have a capsid and phospholipid membrane; but in the nonenveloped virus the genetic material is between these two membranes, while in the enveloped virus the genetic material is inside both membranes.