Ap Bio Who Is Freaking Out!?????????

Test Preparation AP Test Preparation
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<p>
[quote]
can someone explain to me the alternation of generations for plants? my books always have it in a cycle and I don't really understand what it starts and ends with...

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</p>

<p>basically half of a plant's life cycle is in the sporophyte (gamete; diploid) stage, and half of a plant's life cycle is in the gametophyte (spores; haploid) stage. </p>

<p>Sporophyte-->Meiosis-->Gametophyte-->Mitosis?-->fertilization-->sporophyte again.</p>

<p>something like that, i'm not too hot with alternation of generations. just have a general idea.</p>

<p>
[quote]
hi wxmann..</p>

<p>DNA replication moves along the 5' to 3' direction?

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</p>

<p>Yes. DNA polymerase can only add nucleotides to the 3' end b/c it breaks the OH group located on the 3' carbon to do so.</p>

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<p>thanks. i'd also like to know why is a "gamete" is diploid in this case, I always assumed that they were haploid. for some reason this has been confusing me all year.</p>

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<p>Wow, is the grading scale really that easy? IF it is, I'll stop worrying so much... I'm just hoping for a 3.</p>

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<p>Examination Grade ... % of Students Earning Grade</p>

<p>5 - Extremely Well Qualified ... 19.3
4 - Well Qualified ... 20.3
3 - Qualified ... 21.2
2 - Possibly Qualified ... 23.2
1 - No Recommendation ... 15.9</p>

<p>..relax people</p>

85

<p>
[quote]
thanks. i'd also like to know why is a "gamete" is diploid in this case, I always assumed that they were haploid. for some reason this has been confusing me all year.

[/quote]
</p>

<p>yw... and i suck at vocab so I didn't even know gamete was suppose to be haploid lol. I just remembered that a sporophyte is not a spore and a gametophyte is not a gamete.</p>

86

<p>ok, here's a good image of alt. of generations</p>

<p>a sporophyte is NOT a gamete... so sorry about that. It's the actual adult plant. </p>

<p><a href="http://upload.wikimedia.org/wikipedia/en/8/86/Sporic_meiosis.png%5B/url%5D"&gt;http://upload.wikimedia.org/wikipedia/en/8/86/Sporic_meiosis.png&lt;/a&gt;&lt;/p>

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<p>i heard that the "cut points" for each number (1,2,3,4,5) vary from year to year depending on how hard the exam is, is that true?</p>

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<p>ok but it starts with the sporophyte, cause thats what always confuses me the fact that its a circular flow (i don't know where it starts or ends)</p>

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<p>thanks, the chart was really helpful, it was very simple and to the point!</p>

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<p>ahhhhhhhhhhhhhhhhhhhhh</p>

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<p>lol only 40 percent get a 4 or 5, meaning 6 of the 10 ppl next to me will get 3 or less!!!!</p>

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<p>
[quote]
i heard that the "cut points" for each number (1,2,3,4,5) vary from year to year depending on how hard the exam is, is that true?

[/quote]
</p>

<p>Yes these break-off points change from year to year depending on how well students do on the test and (therefore) how difficult the exam is. My teacher explained the whole scoring system as a bell curve with most people in the 3ish range and smaller proportions of people at the high end (5) and low end (1).</p>

<p>Hope that's helpful. AND GOOD LUCK EVERYONE TOMORROW.</p>

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<p>duh</p>

<p>is this your first ap?</p>

<p>EDIT: I'm 1 of the 2 that get a 5.</p>

94

<p>i just finished taking the sparknotes diagnostic test, do you think its prediction of what we'll get is accurate?</p>

95

<p>can somone explain the process of getting RNA ready to make proteins</p>

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<p>oh oh oh..RNA making protein goes like.</p>

<p>Transcription. Translation. Synthesis.</p>

<p>erm? I'll pull the minute details out of the fog that is my brain tomorrow morning if I need to....lol</p>

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<p>Transcription:
DNA is used to make mRNA
RNA is only one stranded
Ts are replaced with Us</p>

<p>Translation:
At a ribosome three letters on mRNA are used to match up with anticodons on tRNA. Each anticodon makes an amino acid.
A chain of amino acids is called a polypeptide chain and is a protein.</p>

<p>Protein Structures:
Primary: Sequence of amino acids.
Secondary: Shape of amino acids (alpha helix or beta sheets)
Tertiary: Shape of whole protein
Quadrary(?): Shape of multiple proteins</p>

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<p>to get it ready though what else happens besides taking out the introns with spilcesosomes (?)</p>

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<p>do we need to know any scientists BESIDES watson/crick</p>

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<p>Transciption, RNA PROCESSING, Translation
<a href="http://i32.tinypic.com/23sd9iw.jpg%5B/url%5D"&gt;http://i32.tinypic.com/23sd9iw.jpg&lt;/a&gt;&lt;/p>

<p>this diagram and explanation helps a lot</p>