<p>I’m having trouble with a few of these questions which appeared in a state-wide test administered recently. I would appreciate any help on them, especially an explanation if possible. </p>
<li><p>If cells in the process of dividing are subjected to colchicine, a drug that interferes with the functioning of the spindle apparatus, at which stage will mitosis be arrested?
a. anaphase
b. prophase
c. telophase
d. metaphase
e. interphase </p></li>
<li><p>What do both mitochondria & chloroplasts have in common?
a. ATP is produced
b. DNA is present
c. Ribosomes are present
d. Only b & c are correct
e. a, b, and c are correct </p></li>
<li><p>Gram-Negative Bacteria
a. lack a second plasma membrane outside the cell wall
b. stain violet when Gram-stained
c. tend to resist many of the body’s natural defenses and antibiotics making many of them pathogens
d. completely lack a cell wall </p></li>
<li><p>All of the following are true about crossing over EXCEPT:
a. it involves the exchange of pieces of chromatids of tetrads
b. the farther away from the centromere, the more likely it is to occur
c. it produces two sets of identical chromatids from a tetrad
d. it results in genetic recombination </p></li>
<li><p>The carbon that makes up organic molecules in plants is derived directly from
a. combustion of fuels
b. carbon fixed in photosynthesis
c. carbon dioxide produced in respiration
d. carbon in the lithosphere
e. coal mines </p></li>
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<li><p>probably prophase because thats when the spindle would be forming and since it couldnt...well mitosis would be halted there.</p></li>
<li><p>Both mitoc. and chlor. produce ATP, both have their own little DNA strands....ribosomes....well, i dunno, but since just a and b is not a choice, i guess ill say a, b, and c, but im not sure ribosomes are IN them...actually i dont think they are.</p></li>
<li><p>B, they stain violet. i love the little guys.</p></li>
<li><p>C. this is kinda obvious. </p></li>
<li><p>carbon fixed in photosynthesis. i love you, RuBP carboxylase (known to all the Campbell's folks as "rubisco"</p></li>
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<li>there's ribosomes in the stroma of chloroplasts and mitochondrial matrix so it should be e.</li>
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<p>edit: I think 3 is c. Gram positive stains purple, gram negative doesn't have enough peptidoglycan to stain purple so it's red or something, and they have some kind of capsule that hides the antigens.</p>
<p>yeah #3 is C now that i think of it. Gram-negatives DO stain violet, but the stain then goes away and its dimmer. and yeah, there are ribosomes in the chloroplast stroma and in the mitochondrial matrix so yeah i was right. and yeah i am passionate at biology and i took ap my soph. year and got a 5 and 800 on bio m/e and what not and ill see y'all at IBO.</p>