Practice Questions for Dr. Welch, Final Fall 2014

Transcription

1 1) Hans Spemann discovered the organizer by transplanting the dorsal lip of one embryo onto the ventral side of a second embryo. The second embryo developed as and Spemann concluded that. A. two embryos connected on the ventral side; the organizer is not present in the dorsal lip B. two embryos connected on the dorsal side; the organizer produces diffusible morphogens C. two embryos connected on the ventral side; the organizer is not present in the dorsal lip D. two embryos connected on the dorsal side; the organizer is not involved in determining dorsal/ventral fate E. two embryos connected on the ventral side; the organizer produces diffusible morphogens 2) An animal has the following properties: constant body temperature, active at a broad range of temperatures, generates heat by metabolism. This animal is a --- A. poikilotherm B. thermotherm C. mesotherm D. endotherm E. ectotherm 3) Fick s law governing the rate of gas exchange in cells give the relationship R=DAΔP/d. Which of the following would NOT increase the rate of gas exchange? A. Increased surface area B. Increased distance C. Increased difference in partial pressure D. Decreased distance E. Peptide/protein, for example IGF1 4) Which of the following description applies to the counter current system in fish gills? A. blood flow is in the same direction as the flow of water B. in a counter current system the incoming water will have a lower po2 than the blood po2 C. in a counter current system exchange occurs along the entire length of interaction (blood with water) E. Both A and C. 5) Which organism uses parabronchi in their respiratory system? A. humans B. amphibians C. fish D. birds E. starfish 6) Which of the following statements about signal transduction is correct? A. A hydrophobic ligand cannot pass through cellular membranes. B. A receptor is a protein to which a signaling molecule binds. C. Signal transduction is a pathway through which a cellular response is converted into a signal. D. Receptor proteins are all located in the cell s plasma membrane. E. A hydrophilic ligand passes through cellular membranes. 7) Which of the following is FALSE regarding signal transduction by GPCRs? A. G-protein coupled receptors act by protein phosphorylation. B. G-protein coupled receptors (GPCRs) are the largest family of receptors in animal cells. C. G-protein coupled receptors activate heterotrimeric G-proteins. D. Activated G-proteins associate with effector proteins that elicit a cellular response. E. Hydrolysis of GTP to GDP inactivates heterotrimeric G-proteins. 8) How was the receptor for insulin discovered? A. A mutation in the dog genome was shown to result in diabetes and was subsequently mapped to the gene encoding insulin. B. Insulin was purified from a pancreatic extract and was shown to cure diabetes when injected into a dog missing its pancreas. C. Radioactively-labeled insulin was bound and cross-linked to its receptor, which was then separated from other proteins by gel electrophoresis.

2 D. Insulin was found in a genetic screen for genes involved in pattern formation in worms. E. Variations in the insulin gene were found to regulate body size in dogs. 9) Which stem cell type can give rise to any tissue in an organism? A. Totipotent B. Multipotent C. Unipotent D. Pluripotent E. Polypotent 10) Which of the following lists represent the four sub-processes involved in development? A. barriers; innate; adaptive; antibodies B. totipotent; pluripotent; multipotent; unipotent C. nuclear transfer; cell fusion; prolonged culture; defined factors D. transcription; translation; replication; decay E. cell division; differentiation; pattern formation; morphogenesis 11) Which of the following is the definition of a model organism? A. An organism that is particularly good looking. B. An organism that is studied by a small number of scientists. C. An organism that is difficult to grow and maintain in the lab. D. An organism that causes human disease and is relatively easy to study. E. An organism selected for study as a representative a large group of species. 12) The Hox genes were discovered in fruit flies by Ed Lewis. Mutations in these genes--- A. cause the appearance of body parts in inappropriate places. B. cause enhanced cell death by apoptosis. C. cause body size differences in dogs. D. cause defects in dorsal-ventral patterning. E. cause abnormal nervous system development. 13) During the falling phase of the action potential (repolarization), which of the following is true? Na + activation Na + inactivation gate K + gate gate A Closed Closed Closed B Closed Open Open C Open Closed Open D Open Open Closed 14) Which of the following animals have the largest numbers olfactory receptor genes (as presented in lecture)? A. Humans B. Rats C. Elephants D. Rabbit E. Dog 15) Select the incorrectly paired associations? A. Nephron and kidney B. Sarcomere and skeletal muscle C. Pituitary gland and ACTH D. T-tubule and hypothalamic axis E. Neuromuscular junction and neurotransmitter 16) Which of the following is NOT an example of cell signaling A. paracrine B. endocrine C. synaptic D. autocrine E. bohr shift

3 17) In response to inputs from the nervous system the medulla of the adrenal gland releases A. aldosterone B. epinephrine C. insulin D. glucagon E. adrenal corticotrophin hormone (ACTH) 18) Which of the following hormones would be expected to interact with a cell surface receptor? A. aldosterone B. testosterone C. insulin E. Only A and B 19) The adrenal gland produces both lipophilic and hydrophilic hormones. Select the best choice regarding the lipophilic hormones? A. The lipophilic hormones do not need a carrier transport and interact with hormone receptors present on the cell surface of responding cells. B. The lipophilic hormones do not need a carrier transport and interact with intracellular hormone receptors present in responding cells. C. The lipophilic hormones need a carrier transport and interact with hormone receptors present on the cell surface of responding cells. D. The lipophilic hormones need a carrier transport and interact with intracellular hormone receptors present in responding cells. 20) Which of the following are selective pressures to maximize gas exchange in fish? A. The amount of oxygen in water is less than that in air. B. The density of water is 800 times that of air. C. Oxygen exchange occurs at moist surfaces.. E. Both A and B. 21) Which of the following statements about hemoglobin is/are true? A. Hemoglobin is composed of four α polypeptide chains, and each chain has a heme group that can bind a molecule of O 2. B. During typical exertion, the hemoglobin in oxygenated blood is 97% saturated with O 2, and the hemoglobin in deoxygenated blood is 20% saturated with O 2. C. As H + concentration increases and as temperature decreases, the affinity of hemoglobin for O 2 increases. E. None of the above 22) The majority of CO 2 is transported in the blood as A. as CO 2 B. as HCO 3 - C. bound to hemoglobin (carboxy hemoglobin) D. phosphoglycerate E. H 2 CO 3 23) Which of the following adaptations makes fish gills particularly efficient at gas exchange? A. Water flow over gill surface B. Blood flow in gills C. Gill filaments D. Countercurrent exchange E. Oxygen deficient blood 24) Which of the following is NOT true of the events that occur following the binding of a neurotransmitter or hormone to a ligand-gated ion channel? A. It can result in channel opening and membrane depolarization B. It can result in channel opening and membrane hyperpolarization C. It can result in a graded change in membrane potential

4 D. hyperpolarization below -80 mv can result in an action potential E. depolarization above -55 mv can result in an action potential 25) Which of the following macromolecules in an animal s diet would contribute nitrogenous groups that must be eliminated? A. starch B. RNA C. triglycerides D. all of the above E. none of the above 26) You are an engineer at a power plant that creates large volumes of hot water, which disrupts the ecosystem of the river it drains into. Another part of the plant requires warm oil, and the plant uses large amounts of energy to heat it. Inspired by mechanisms to minimize heat loss in whales, you save energy and benefit the environment by doing what? A. running the oil pipes under the river after dumping in the hot waste water B. running the oil pipes around the water pipes in a countercurrent flow C. running the waste water and oil through a single pipe D. adding a sensor, integrating center and effectors to control temperature in both pipes E. running the oil pipes around the water pipes in a concurrent flow ANSWERS ON THE NEXT PAGE

5 QUESTION ANSWER QUESTION ANSWER 1 E 14 C 2 D 15 D 3 B 16 E 4 C 17 B 5 D 18 C 6 B 19 D 7 A 20 D 8 C 21 E 9 A 22 B 10 E 23 D 11 E 24 D 12 A 25 B 13 C 26 B