[Q]: Two friends went to the doctor because they weren't feeling well. As it turns out Danny had a condition called hypercalcaemia, while Greg had hypocalcaemia. Which friend didn't have neuromuscular excitability? Hint: Excess intake of calcium may cause hypercalcaemia. However, because calcium is absorbed rather inefficiently by the intestines, high serum calcium is more likely caused by excessive secretion of parathyroid hormone (PTH) or possibly by excessive intake of vitamin D, both which facilitate calcium absorption. It may also be due to bone destruction that occurs when tumours metastasize within bone. All these conditions result in excess calcium salts being deposited in the heart, blood vessels, or kidneys. Symptoms include anorexia, nausea, vomiting, memory loss, confusion, muscle weakness, increased urination, dehydration, and metabolic bone disease. Chronic hypercalcaemia typically leads to calcification of soft tissue and its serious consequences: for example, calcification can cause loss of elasticity of vascular walls and disruption of laminar blood flowand thence to plaque rupture and thrombosis. Conversely, inadequate calcium or vitamin D intakes may result in hypocalcaemia, often caused also by inadequate secretion of parathyroid hormone or defective PTH receptors in cells. Symptoms include neuromuscular excitability, which potentially causes tetany and disruption of conductivity in cardiac tissue.
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[A]: Danny

[Q]: David is investigating the breathing process of different organisms. He found that humans have alveoli to help them with gas exchange. He got curious about other organisms that do not have alveoli. To compare these two groups he labeled organisms with alveoli as group A and organisms without alveoli as group B. Which group may not have network of small blood vessels in the lungs, group A or group B ? Hint: The lungs of mammals are unique in having alveoli . These are tiny, sac-like structures. Each alveolus is surrounded by a network of very small blood vessels (see Figure below ). Because there are millions of alveoli in each lung, they greatly increase the surface area for gas exchange between the lungs and bloodstream. Human lungs, for example, contain about 300 million alveoli. They give the lungs a total surface area for gas exchange of up to 90 square meters (968 square feet). That's about as much surface area as one side of a volleyball court!
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[A]: group B

[Q]: Doctors studied the blood of 2 sisters, Ann and Julie. Ann had sickle cell anemia, Julie did not. Which sister had fewer cells that had a difficulty passing through the smallest blood vessels? Hint: Another example of incomplete dominance is with sickle cell anemia, a disease in which a blood protein called hemoglobin is produced incorrectly. This causes the red blood cells to have a sickle shape, making it difficult for these misshapen cells to pass through the smallest blood vessels. A person that is homozygous recessive ( ss ) for the sickle cell trait will have red blood cells that all have the incorrect hemoglobin. A person who is homozygous dominant ( SS ) will have normal red blood cells.
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[A]: Julie

[Q]: Joe is at a party and carrying around a can of beer that he has had in his hand for awhile. He bumps into Sally, and they begin chatting. During their conversation, Sally notices the beer in Joe's hand, and remarks that a beer sounds like a good idea. She heads over to the refrigerator and grabs a nice cold one and pops it open. She takes a sip while the two continue their chat. The molecules in whose can of beer are moving faster? Hint: Liquid water is a fluid. The hydrogen bonds in liquid water constantly break and reform as the water molecules tumble past one another. As water cools, its molecular motion slows and the molecules move gradually closer to one another. The density of any liquid increases as its temperature decreases. For most liquids, this continues as the liquid freezes and the solid state is denser than the liquid state. However, water behaves differently. It actually reaches its highest density at about 4C.
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[A]:
Joe