USABO 2011 Discussion!

<p>so does that mean all were false? or was 3 true. cause i thought 1 said something like “deeper”, not “thicker” so i thought that was T, but its probably F.</p>

<p>Due to the serial position effect, my memory of the intermediate questions order wasn’t very accurate, to say the least. Regardless, this is a very comprehensive list I remembered.</p>

<ol>
<li>Hydrogen Bonding – E</li>
<li> Lowest pH - lysosome C</li>
<li>lipids –E
Similarities of nucleotides and amino acids
Presence of nitrogen, phosphate bonds (I believe some amino acids do, at least), may be helical, and branching (not sure)</li>
</ol>

<p>Measuring size of protein
Gel electrophoresis and something else, I believe.</p>

<p>pH of 5.7
7.0 x 10^-5 M</p>

<p>Chloroplast
Bound by a membrane with cristae</p>

<p>The pictures of plant tissue in order
I think it was parenchyma, sclerenchyma, and collenchymas</p>

<p>Picture of b)
Stem</p>

<p>Root meristems
12</p>

<p>Picking up log to make campfire
Water</p>

<ol>
<li><p>A –> B–> C –> D….
Negative feedback inhibition</p></li>
<li><p>Allosteric regulation
F binds to a different site, thus inhibiting B</p></li>
</ol>

<p>Lack of restriction enzymes in bacteria<br>
A – bacteriophages could easily lyse</p>

<p>Drosophilia embryogenesis
I put bicoid gene.</p>

<p>Light experiment
Not sure, but there were conflicting answers, so it had to be either A,C, or E. I thought the percent transmission of the first curvette would be double that of the second, so I think that was C?</p>

<p>Filtrate in nephron sequence
4,3,1,5,2 I think? Whichever went proximal, descending loop, ascending loop, distal, collecting duct</p>

<p>Water potential
-.8 MPa</p>

<p>Sodium-potassium pump
Thought it was chemical membrane potential difference.</p>

<p>Hemophelia
Boy with two carrier parents</p>

<p>AabbCCdd probability?
1/128</p>

<p>Heterozygous probability
I’m pretty sure I forgot to answer this one haha.</p>

<p>Lysine vs. glycine
negatively charged side chain</p>

<p>John the runner
Not sure about this one. What are your thoughts?</p>

<p>Respiratory acidosis
Decrease ventilation, Increase PCO2</p>

<p>Insecticide resistance
Best choice is mutation. Although I think the natural selection (don’t remember wording) choice is also a viable option.</p>

<p>Phylogeny tree
I. pollen
IV. flowering</p>

<p>E, the angiosperm</p>

<ol>
<li>Cladogram
I thought it was three Howling + spider + ……</li>
</ol>

<p>I. cartilage heals slowly since it is a deep tissue
II. the intestine has a large surface area due to cilia
III. fat is a type of connective tissue because….
E- all of the following incorrect</p>

<p>Adaptive radiation in Darwin’s finches
C – sudden diversification</p>

<p>Cross-sectional area graph
Mountain slope shaped one</p>

<p>Which of the following are endothermic?
I. Blue fin tuna
II. Salmon
III. Great white shark</p>

<p>I,III</p>

<p>Predecessors of plant and animals
Both had</p>

<p>4 major biomes
Forests, taiga, tundra, desert</p>

<p>Different vegetation
Temperature and precipitation</p>

<p>Starvation & steroids
Inducer?</p>

<p>Reciprocal altruism
II, IV? I think II was non-kin</p>

<p>Competition among plants
E all or none of the above. Not sure how this answer choice functions…I’ve never seen an all/none of the above</p>

<p>Muscle contraction
D – tetanus as a repetitive stimulation?</p>

<p>Maple trees
population</p>

<p>Mammals
I think it was I,IV, V, but I don’t really remember</p>

<p>Hardy-weinberg population
E -1 million and no other surrounding populations</p>

<p>Evolution
Allele frequencies</p>

<p>O2 produced in photosynthesis
Used in cellular respiration</p>

<p>Select all of the following about sperm
Haploid and 23 chromosomes.</p>

<p>The tendency for something to move towards a climax community
succession</p>

<p>pH of 5.7 was not 7.0 * 10^ -5. It was 2.0 * 10^-6.</p>

<p>Gymnosperms can also have pollen for the phylogeny (49?), and isn’t it 1 root meristem since it was a taproot (the other 11 were lateral meristems)? And fat is a connective tissue. I don’t remember, but wasn’t it asking what was false with muscle contractions?</p>

<p>Adipose tissue is connective.</p>

<p>Wasn’t the adaptive radiation the one with the word, niche in it?</p>

<p>It’s parenchyma, collenchyma, sclerenchyma</p>

<p><a href=“http://2.bp.blogspot.com/_cBCml_aE9t4/TGyTqIfTo2I/AAAAAAAAAOs/jjtlqujklaE/s1600/ground+cells.jpg[/url]”>http://2.bp.blogspot.com/_cBCml_aE9t4/TGyTqIfTo2I/AAAAAAAAAOs/jjtlqujklaE/s1600/ground+cells.jpg&lt;/a&gt;&lt;/p&gt;

<p>Wha was the heterozygous, maple trees, and bacterial resistance one?</p>

<p>I meant that, Apoc314, thank you for catching that. billin12345, i agree that gymnosperms produce pollen, but wasn’t the question asking which group that had both capabilities? Lateral meristems are still considered to be root meristems. I don’t think one was an option either. Fat is a connective tissue, but the justification for it, I believe, was incorrect. The muscle contractions question was asking which of the following is false, so the answer choice with tetanus as a repetitive stimulation is incorrect.</p>

<p>Tetanus is repetitive stimulation right?</p>

<p>I got A for that question something about calcium ions and muscle length</p>

<p>Apparently the lipid one is only two choices :(</p>

<p>I got B (gel electrophoresis) and C (size-exclusion i think) I think it was just B though. Any confirmation?</p>

<p>Tetanus is prolonged contraction.</p>

<p>Tetanus is repetitive stimulation in short intervals, so it’s a true statement, making it the wrong answer for the question.</p>

<p>I put A.</p>

<p>Tetanus is a sustained contraction. Campbell/Reece proves: “when the rate is high enough that the muscle fiber cannot relax at all between stimuli, the twitches fuse into one smooth, sustained contraction called tetanus.” (pg. 1100 8th edition)</p>

<p>Nearly positive about the lipid one. I. they’re hydrophobic. II. nonsaturated fats are liquid at room temp. III. no idea, but it was probably true.
According to wiki, Size-exclusion chromatography (SEC) is a chromatographic method in which molecules in solution are separated by their size, not by molecular weight. I think it might just be B then as I posted above.
Not so sure about the similarity of the picture of the ground tissue you found, especially considering it was posted on a blog.</p>

<p>Lipid was only II and III</p>

<p>You said Electrophoresis and something else? Yeah, Im pretty sure I got it wrong. :P</p>

<p>No, Im pretty sure it’s the exact one. The blog pic</p>

<p>tetanus: repetitive stimulation of a muscle at intervals short enough to provide summation
[Muscle</a> Mechanics and Physiology](<a href=“http://d3jonline.tripod.com/05-Cellular_Physiology/Muscle_Mechanics_and_Physiology.htm]Muscle”>Muscle Mechanics and Physiology)</p>

<p>Man, I missed some of the easiest questions like succession, saturated lipids are solids, lysosomes have low pH, maple trees are a population, etc. LOL. Fail @ me. Grr…</p>

<p>Here’s what I remember (and what I believe to be the answers [I could be wrong]):</p>

<p>What is not true of sex-linked inheritance (or something to that effect):
Answer: If parents don’t show signs of disease, offspring won’t have it</p>

<p>Myelin sheath analogy about rats eating an insulated wire:
Answer: Demyelination of a neuron</p>

<p>Which is not true of plant cells?
Answer: Chloroplast has one membrane which leads to stoma</p>

<p>Cross sectional area diagram:
Answer: Capillaries > veins > arteries
(the graph should’ve went from low, to high, to medium in the answer)</p>

<p>Coefficient of relatedness: Uncle + Nephew
Answer: 0.25</p>

<p>The question said which is not true of a maternal inheritance, I thought it was talking about mitchondrial inheritance and not sex-linked as everyone says?</p>

<p>I don’t remember that question?</p>

<p>Was there actually a hemophilia question? o.O</p>

<p>I definitely know what you mean, Infrared. You should probably read my post before posting old questions, but thank you for posting a new one (coefficient of relatedness).The answer is .25. It also helps to provide some sort of justification for your answer. [Introduction</a> to population biology - Google Books](<a href=“Introduction to Population Biology - Dick Neal - Google Books”>Introduction to Population Biology - Dick Neal - Google Books)</p>

<p>@Blebbing: Edited. My apologies by the way.
For some of the questions that you had already posted, I merely added some details to get closer to matching the actual question.</p>

<p>i am sure question number one has no correct answer. the question read: “all of the following involve h-bonds except?” and proved answers A-E with E being “all of the above.” However, the choice should have read E “none of the above” due to the double negative, as all actually do indeed represent hydrogen bonds. (some put enzyme-substrate but those interactions are definitely mediated by H bonds). what do you guys think? </p>

<p>another question that had no correct answer was the chlorophyll one that read “cholorophyll includes all of the following except?” one of the choices said single membrane that folds into stoma which is incorrect and another said double membrane with crista. are we in accordance here or was that just me? </p>

<p>also, does anyone have any idea on how to do the spectrophotometry question? i think the velocity of the light in the second case was doubled (or was it the amount of pigment?). did you guys put double the absorbance? </p>

<p>and what did you guys put for the most important factors for plant growth? latitude and temperature or soil and precipitation.</p>

<p>What is the bacterial resistance, maple tree, and hemophilia question (based off on blebbing)</p>

<p>I put cristae. You got everything else right then</p>

<p>The bacterial question was what would happen if bacteria has no restriction enzymes, and so it has no resistance to bacteriophages (because it can’t lyse them).</p>

<p>Blebbing said something about antibiotics?</p>