Marconis

Please delete. Found literature that answers my question.

I am pretty good at drawing MO diagrams when they are simple. For instance, I can start from 1s and go up to, say, 2p and draw everything in (e- in proper location). If it said something like, "Draw the MO diagram of N2" or NO- I'd be able to do it very easily. Despite this, I get very confused when it throws in hybrid orbitals. For example, if the question says, "Using an sp3 orbital on carbon and a p orbital on Fluorine, construct the MO energy diagram" I don't understand this, because isn't Fluorine in CH3F also sp3 hybridized? It has 3 lone pairs and a carbon next to it, yeah? "4 groups". But is it asking for a hybridized orbital of the F, or just one of the 3 p orbitals? Even so-----I wouldn't know how to draw the diagram for this. If it asked me to draw the structure of the compound with its hybrid orbitals shown, I'd be able to do it easily. But, in the "step" diagram, if you will, I am completely thrown off. How would you do this? Sorry if this is a confusing question! THANKS!

We had to do a t-test analysis for a lab, and I am confused as to how to answer the question of significance in terms of null/alt hypothesis using confidence intervals. We were to measure the height and weight of 7 males and 12 females in the lab. After doing so and collecting all the data, I got the following: Confidence Intervals based on 95% certainty: Male Height (Mean 174.786): +/- 5.28cm= 169.506cm - 180.066cm Male Weight (Mean 78.143): +/- 20.339kg= 57.804kg - 98.482kg Female Height (Mean 160.83): +/- 5.2426cm= 155.587cm - 166.0726cm Female Weight (Mean 54.30): +/- 8.627kg= 45.672kg - 62.927kg I calculated the CI by multiplying the SE by the confidence level. Now, the question asks: Is there a significant difference between the height of males and females in this population of humans? and then the same for weight... I am unsure how to answer this in terms of analysis with confidence intervals. Null hypothesis states that there is no difference between the mean values of populations 1 and 2, and alt. hypothesis states that the mean values are not equal and that the difference between them is statistically different. Can you give me hints as to how to answer this in terms of CI/t-test analysis? Thank you very much, I appreciate it.

Why is the default potential of a photoreceptor cell hyperpolarized? Why is it that more neurotransmitter is released in the dark than in response to light? I can't understand this and my textbook does not go into why it is the case, it just states it as a matter of fact and being "unique". Thanks!

This isn't a homework question, I am just curious. With both fertilization and chemical synaptic transmission, I have learned that Ca+ causes a fusion of corticle granule and synpatic vesicles, respectively, to the plasma membrane. My textbook never states why, nor has my professor. I am confused as to how Ca+ induces such an instance. Could anyone give me some things to think about? Thanks.

Nevermind! It all just hit me.

If the parents (of the F1 gen) of a dihybrid cross are not true-breeding, will you still see a 9:3:3:1 ratio in the F2 generation? I did a bunch of dihybrid crosses on Kansas State Uni's website (found it on google), and literally all of the F2 generation punnet squares were not in 9:3:3:1. For example, one had 10 of a certain phenotype, another problem had 8 for a given phenotype. I started to scratch my head, because all of the questions that I answered were correct (like when it asked for a given genotype number, it'd be correct, etc). Something about genetics really crushes my brain. Sorry if I sound stupid. See? http://www.ksu.edu/biology/pob/genetics/… Not 9:3:3:1, and it's a dihybrid cross. Let's say A/a stands for hair color, brown is dominant. T/t stands for height, tall is dominant. If you look at this square, isn't it only showing 8 Brown/Tall, and 8 Brown/Short? (1:1) It says a dihybrid cross is defined as: "a cross between identical double heterozygotes."

Thanks fellas

Yeah I always thought that n referred to chromosomes and it seemed incorrect to refer to the DNA duplication as 4n, so I was getting thrown off. Thanks.

In my GEN BIO 1 course we just did cell division. I breezed through the chapter since it was a nice review from AP Biology. All of the sudden, when I got to lecture, though, I was slammed with confusion. On my professors powerpoint, for mitosis she had labeled Interphase as going from 2n--->4n. This made no sense to me. Isn't the DNA replicated in S phase, and the number of chromosomes remains the same? So for instance, if this was a human cell and there were 46 chromosomes, wouldn't this indicate that there are now 92 chromosomes (4n)? 92 chromatids, yes, but chromosomes? Seems weird. For prophase all the way to telophase she has "4n" underneath each phase picture, until the cells are ready for cytokinesis in which it says "2n" Again, for meiosis, she did the same thing. I am very confused on this...I never knew that the cells could ever have 4n. The whole class seemed to be confused by this as well. Any clarification would be great!

I just accounted for the 10 months that were used. I guess that's incorrect? Hey I got help on another forum, I truly feel like an idiot for not doing it properly . Thanks anyway for responding/

Sorry, should have stated my major: biology. Calc 1 covers differentiation while Calc 2 is integration I believe. I don't think I'll be taking any math intensive courses in the future.

Here's what I did: To find annual growth rate, I did 16-2/10. That's 1.4cm per year, average. To reach a meter in length, I did 100=1.4x, then got x=71.43. I divided that by 2 (2 months a year) and got 35.7 years. Then, for average summer growth rate I did 16-4.5/5 and got 2.3cm. Is this correct?

I'm a sophomore, and since I am pitiful at math I had to take the slow route in order to build up to Calc 1 (College algebra, precalc to here). I transferred schools after last semester, and I didn't realize but they allow Introductory Biometrics to fulfill math as an alternative to Calc 2. I hear horror stories about calculus in general (no matter what the level) and me being terrible at math myself makes matters worse. So, I am wondering, if I pass Calc 1 this semester, would it be more wise to go the biometrics route or just go into calc 2? What do you guys think? Thanks

We are to find the annual growth rate of a fish from 2003-2007. The measurements are taken in March and September of the same year. This is throwing me off in determining the growth rate. In general if it just said the year and then the measurement (without the two different months), I'd subtract the first year measurement from the final year measurement and divide by 4. However, when two months are involved, this doesn't seem to work. This also leads me to believe that you need to account for 5 years instead of 4. Any advice on how to go about it? March 03 : 2cm Sept. 03: 4.5cm March 04: 4.7 Sept. 04: 6.6 March 05: 7.0 Sept 05: 9.2 March 06: 9.3 Sept 06: 12.0 March 07: 12.5 Sept 07: 16.0

Thanks for your help, cypress.

Ah, you're totally right man. I found a formula: one space on the OM= X spaces on SM x .01mm/ 10 Thanks so much for your help. So are these all right? I found an easy formula for the last part too Number of SM units in 10 OU @4X: 25 One OM unit= .025mm,25um Number of SM units in 10 OU @10X:10 One OM unit=.01mm, 10um Number of SM units in 10 OU @40X: 2.5 One OM unit=.0025mm, 2.5um By doing (length of one division of the ocular micrometer)(number divisions counted as length Paramecium caudatum). So (80)(2.5) 80 OU divisions @ 40X= 200um 70 OU divisions @ 40X= 175um

Not quite sure what you're saying. Through my lab manual it is confirmed that 100 stage units is equal to 1mm.

I'm pretty sure each is .01mm or something and the whole stage glass is 1mm (with all the units).

If the total length is 2.0 mm, that means that the Paramecium is 2000 micrometers. That seems pretty false...what am I not grasping here?

Glad to hear the first is correct. But as for the second, I was wrong? Damn...I remember my lab instructor telling my bench partner that's how to do it. So I have to multiply, not divide?

So in my bio class we had our first lab as a microscopy lab. Since I am a transfer student, they want me to take freshman bio even though I got a 5 on AP exam which exempt me from freshman bio at my other institution. I state that because I went in all cocky to this lab since I have used microscopes many times before this in my other classes such as Invertebrate Zoology. In that we had a microscopy lab, but we never dealt with a stage micrometer for some odd reason. When this was foreign to me, I felt stressed and embarrassed for myself and the instructor (he was going nuts trying to explain things to people about it) . So, since I am new to it, I want to know if these calculations are correct... At 4x objective, if 25 stage units fit into 10 ocular units, then is that equal to .25 mm and 250 um? I just did 25x.01mm and then got my answers. I feel like that's wrong. From an earlier determination that 2.5 stage units fit into 10 ocular units at 40x objective, I calculated that 80 ocular units is the equivalent to 320 um. I did this by doing 80/2.5, multiplying that by .01 and then converting mm to um. Correct? I hope I'm right, I want to stop feeling like an idiot over such a simple thing Thanks in advance.

Okay, so...this is the third time I have seen a question of this exact form, and have gotten it right both times. This time, I got it wrong, and am completely stumped as to why! Any help is greatly appreciated. A voltaic cell consists of an Au/Au3+ electrode (E° = 1.50 V) and a Cu/Cu2+ electrode (E° = 0.34 V). Calculate [Au3+] if [Cu2+] = 1.20 M and Ecell = 1.13 V at 25°C What is the correct answer? Less negative is 1.50, reduced, .34 flipped to -.34. Overall E^o is 1.16 1.13=1.16-(.05916/6)log(1.20/x) -.03=-.00986log(1.2/x) 3.042=log(1.2/x) -2.963=logx 10^-2.963=.001

Ah, I figured it out.

For a lab we did on Tuesday, we are required to do a flowchart (in order to assist us in part two of the lab this week). I emailed my lab TA my flowchart, and she told me I had the right idea but should start out with OH- so that I can have all filled up ppt (precipitate) and spn (supernatant) throughout. For some reason, I am having trouble on linking them together. The OH through H+ experiments are all a sequence, but the PO4 and Fe(CN)6 are both independent, so I am unsure how to factor that in. Also, as you can see, the PO4 experiment yields no spn, so that is confusing me as well. Thanks in advance for any assistance. http://s160.photobucket.com/albums/t179/Marconisradio/?action=view&current=Picture1-2.png