Imagine that, because of (or despite) your experiences in this class, you change your career choice and decide to become a doctor. Somehow, you are admitted to medical school, pass with flying colors, and end up as a general practitioner with a thriving practice.

Doctor, the following nine questions concern nine patients of yours.

1. Ms. Susan E. Pigg is a 45-year-old woman with diabetes insipidus. (This is not the same disease as the one you have to take insulin shots for; that's diabetes mellitus.) Mrs. Pigg's primary symptoms are that she is constantly thirsty, has to drink a lot of water, and produces large amounts of dilute urine no matter how much or how little fluid she has been drinking. Which of these conditions could be causing her disease?

Her hypothalamus can't produce ADH.
Remember, ADH = anti-diuretic hormone. ADH makes the loop of Henle more permeable to water going out -- meaning that the urine becomes more concentrated. No ADH means less water leaves the filtrate, thus urine stays dilute.

2. Mr. Raymond Zohrback, age 63, had a heart attack a few months ago. His heart rate ever since has been irregular, and you advise that he have an artificial pacemaker implanted. Which of the following parts of Mr. Zohrback's heart may have been damaged?

sinoatrial node

3. Mr. Solly Gohatchia, age 72, has just had a stroke. His cerebellum was damaged. What symptoms would you predict he would show?

loss of muscular coordination

4. Mr. Joseph Kamell, age 55, has smoked several packs of cigarettes a day all his life. He now has a condition called emphysema, in which the air sacs in his lungs become increasingly less elastic and expandable. What are these air sacs called?

alveoli

5. Mr. Halley Tosis, age 67, comes in with a painful, blistered skin rash called shingles. Which virus causes shingles, by remaining "dormant" inside cells for many years after the initial infection?

chickenpox

6. Ms. Polly Warner-Kracker, age 24, has a severe infection known as pelvic inflammatory disease, or PID. You know that PID can cause scarring and even blockage of the Fallopian tubes. What could be the end result?

Egg cells can no longer reach the uterus from the ovary.

7. Mr. Dan de Torpedoes, age 37, has developed an itchy rash between his fingers. You scrape some of the affected skin onto a microscope slide, examine it under the microscope, and find a parasitic organism, about half a millimeter long, called Sarcoptes. Sarcoptes has an exoskeleton, a head with a mouth, and four pairs of stumpy legs. It looks like this:

[image here]

(By the way, human infestation with Sarcoptes parasites is known as scabies.) What phylum does Sarcoptes probably belong to?

Arthropoda
Those legs were small, but they're definitely segmented. That's the big tip-off. Body segmentation was visible too.

8. Ms. Sarah N. Dipidee, age 21, comes in with a terrible cold, which she apparently caught from her roommate at UCA. You are certain that this particular cold virus will not bother Ms. Dipidee again. Why?

Memory cells are being produced during her immune response against the virus.

9. "Froggy" Wendell Cortin, age 7, has unusual skin webs between some of his fingers. What should have happened, but didn't, while little Wendell was developing?

apoptosis
Specifically, apoptosis of the cells between his developing fingers.

10. Deoxygenated blood passes through the __, which drain into the ___, which enter(s) the ___ of the heart.

veins; venae cavae; right atrium

11. Bacteria regularly exchange with each other small loops of DNA. These are

plasmids

12. An example of an organism with an open circulatory system would be

a cockroach

13. Which of these organisms is a member of the Plantae?

a pine tree

14. A sperm cell breaks through an egg cell's surrounding protective layers with the help of an organelle called the acrosome. The acrosome is

a sac of enzymes

15. Which of these is a real difference between frog and human embryos?

Human embryos form amniotic membranes; frog embryos do not.

16. A crab, a dragonfly, and a scorpion all have legs made up of many joints. What other feature would you expect them to share in common that is not found in any other of the phyla we have covered?

a tough, plated exoskeleton made of chitin
These three organisms are classified in the Arthropoda. "Body divided into segments" is found in Annelida. "Bilateral symmetry" and "complete gut" are found in many phyla, and "notochord and gill slits," of course, are found only in Chordata.

17. Air is brought into the lungs by a single tube, the trachea, which then divides into two

bronchi

18. When the Pacific giant clam, Tridacna gigas, reproduces, the clams send great clouds of eggs or sperm out into the sea water in which they live. This results in

external fertilization

19. Vertebrates go through an embryonic stage that is basically a solid ball of cells called a ___. The solid ball then ________.

morula; hollows out to form a blastula

20. Unlike other immune cells, T cells complete their development in a gland called the

thymus

21. A mutant fly is discovered with legs growing where wings would normally be located. This is probably caused by

a mutation in a homeotic gene

22. Which of these facts does not especially support the theory of symbiogenesis (a.k.a. endosymbiosis)?

chloroplasts carry out photosynthesis
All the rest are hard to explain unless one accepts that chloroplasts evolved from bacteria that once lived inside an early eukaryote.

23. Watch a snail crawling on the glass walls of an aquarium. You may see the snail rasp at the glass with a tongue-like organ studded with rows of tiny teeth. This organ is called the

radula

24. Certain mildew-like organisms, called labrynthulomycetes, are multicellular, but are classified in the Kingdom Protista. What would be the reason for this classification?

absence of extensive cell differentiation

25. Many fungi absorb nutrients from dead organisms, such as fallen tree trunks, roadkilled armadillos, or Chinese takeout food left for too long in the fridge. What word describes this lifestyle?

saprophytic

26. Which of the following describes what happens when a stomate is opened on a leaf?

CO₂ goes in and water vapor goes out

27. Which of these is a chordate that lacks true bone?

shark

28. After World War II, the Soviet psychologist A. R. Luria studied and treated a soldier named Zasetsky, who had suffered a severe bullet wound to the head in combat. The injury damaged several parts of his brain. Zasetsky lost his ability to calculate, his ability to comprehend and use language, his senses of direction and space, and some of his ability to move. He also lost much of his memory and much of his sight. However, he slowly retaught himself how to write, and-slowly and painfully, over twenty-five years-wrote a 3,000-page memoir of his life (published under the title The Man with a Shattered World). Which part of Zasetsky's brain was apparently not damaged?

the frontal lobes of the cortex
This is a true story, by the way! Remember that the frontal lobes deal (among other things) with motivation, planning, complex tasks, and so on -- all of which you'd need to do what Zasetsky did, especially under the unbelievable handicaps he had.

29. Which of these animals has no true tissues?

sponge

30. While swimming in the tropical seas off the coast of Australia, you are stung by a swimming marine organism called Chironex fleckeri. In the five minutes or so before you die horribly, you recall that this organism must belong to the phylum

Cnidaria
Chironex fleckeri is better known as the Australian box jellyfish.

Questions 31-34 refer to this drawing, depicting two nerve cells. Some parts are labeled.

[image here]

31. What part of the nerve cell is #1?

axon

32. What part of the nerve cell is #2?

cell body

33. What is shown happening at the part labeled #3?

neurotransmitters are being released into the synapse
NOTE: This question was deleted from the exam, when I realized that I hadn't actually drawn the release of neurotransmitters. . .

34. Where would you expect to find voltage-gated sodium channels?

1, 2, 3, and 4

35. Evolutionary biologists used to think that the phylum Arthropoda was closely related to the phylum Annelida, perhaps even evolving from an annelid ancestor. What characters, common to both phyla, could have given them that impression?

both have segmented bodies

36. Which of the following results would occur if the "commanders-in-chief" of the immune system were destroyed?

Both cellular and humoral immune responses would be compromised.
The "commanders-in-chief," of course, are the CD4+ T lymphocytes, or "helper T cells."

37. Which of these phyla contains the greatest number of species?

Arthropoda

38. Generally speaking, the loop of Henle concentrates its filtrate in two ways: Ions leave (and enter) the tubule by ___, and water leaves by ___.

active transport; osmosis

39. Which major vessels carry blood to the heart?

venae cavae and pulmonary vein

40. Evolutionary biologists have traditionally considered the Platyhelminthes to be the most primitive bilaterally symmetrical animals. What do they lack that is present in all other bilateral animals?

an anus

41. When you draw a very deep breath, you are using a muscle called the

diaphragm

42. The blue mold commonly found on spoiled food has a downy, almost hairy look to it. This is caused by the presence of many fine filaments of cells known as

hyphae

43. The Rous sarcoma virus, which causes a type of cancer in chickens, is a retrovirus. This means that it

contains only RNA

44. Nutrients made in the leaves by photosynthesis pass to all parts of a vascular plant through

phloem

45. Which components of your blood are most active in clotting?

platelets

46. Actor Christopher Reeve essentially severed his spinal cord, at a point located high in his neck, in a riding accident in 1995. He is currently unable to do all of the following except:

withdraw his hand and arm from a sudden painful stimulus
This is a reflex -- and it requires only neurons running to and from the spinal cord, and in the cord itself. It doesn't involve the brain at all.

47. The only character that chordates do not all have at some point in their lives is:

hair

48. Blockage of many lymph vessels in a part of the body is likely to cause

swelling of the affected body part

49. Based on what you know about the function of the excretory system: which of these animals would you expect to have the longest and largest loop of Henle?

desert kangaroo rat
Think: Which one lives in the driest environment, and has the greatest need to conserve water?

50. What is the capital of the United States?

Washington, DC
None of the rest exist -- at least, not in our spacetime. . .