Muddiest Points 1

Muddi est Points 1

Use of other compo unds as reduct ants in the electro n transp ort chain. To obtain energy , we and many bacteri a perfor m aerobi c respira tion which strip electro ns from glucos e and send them throug h an electro n transp ort chain to end up with oxyge n (oxyge n is the final electro n accept or). Some bacteri a do not perfor m aerobi c respira tion, they perfor m an alterna tive form of respira tion (anaer obic respira tion) where the electro ns end up with a chemic al other than oxyge n. We did not talk much about these other compo unds, becaus e there are a numbe r of them, but the tend to be nitroge n, sulfur or carbon ate compo unds.

ETC. I was confus ed about the electro ns. Maybe it would be helpful to follow the path of the electro ns in the ETC. My diagra m did show the path of the electro ns (but realize that the electro ns at the start are being carried by NADH or FADH 2. Also see fig 5.12 and 5.18 in your text.

What do we need to know for the Kreb’s cycle? I assum e you mean what do you need to know for an exam. Just know the summa ry reactio ns and that it is a cycle.

Ferme ntation and the produc tion of ATP.

Know that fermen tation is a proces s that uses glycol ysis to produc e the ATP. Then know that to regene rate NAD+ so that glycol ysis can contin ue, you perfor m one or two chemic al (ferme ntation ) reactio ns where pyruva te is conver ted into some fermen tation end- produc t such as lactic acid or ethano l.

ATP Produc tion. I have a hard time with this even though I had it in A & P. See if these videos help: http://s pot.pcc .edu/~j volpe/ b/bi10 1\bi10 1lec\ex traStuf f\Chap ter_8\8 _1_1a _plain. html http://v ideo.g oogle.c om/vid eoplay ? docid= - 82522 47314 22533 4487& sourcei d=sear chfeed

Much of this is review of other classes , so how much do we need to know . .. for the exam. Anoth er person asked about what inform ation is crucial inform ation, especi ally in the readin g, (things we will be tested on).

Genera lly speaki ng, from the text, I only ask you to know the genera l topics and overall picture of things covere d in the readin g. For materi al that is covere d in the lecture I expect you to know it all unless I specify otherw ise. Perhap s the second person is asking “What will we be tested on?” If so, I am afraid I do not answer that becaus e a student who only knows what will be on the exam is not a very well rounde d student .

Worm s/helm inths. What groups are flatwor ms. Which groups are all parasit ic.

There are three groups of helmin ths you need to know. Tremat odes, cestod es and nemat odes. Lumpi ng this 3 groups as helmin ths is probab ly a mistak e, as the tremat odes and cestod es are flatwor ms (phyla platyh elmith es) and the nemat odes are round worms (phyla nemat odes). Flatwo rms are as differe nt from round worms as they are from us. All tremat odes and cestod es are parasit ic. Some other flatwor ms are not. Some nemat odes are parasit ic, some are not. We are only studyi ng the parasit ic ones.

How much info about each species do we need to know since some were elabor ated on more than others? A second student asked someth ing similar and for a list of sympt oms, treatm ents, and disease progre ssion for each would be helpful . For specifi cs, you only need to know what we covere d in the lecture , if we did not elabor ate on someth ing, then I will not “elabo rate on it” in an exam questio n(s). If we did, then I may. I genera lly did provid e sympt oms and if it was import ant, the disease progre ssion for the parasit es that we covere d. If you desire more details, see the text or some online materi al. Especi ally with treatm ents, you may need to go online.

How can a macro phage carry a pathog en around in the body w/o dying before hand? Why does the body not preven t the spread of the disease ?

Some pathog ens can infect and grow in macro phages or other white blood cells. Depen ding on the species , they often reprod uce inside until the kill and lyse the white blood cell. This takes time, giving the white blood cell plenty of time to move around in the body. After all, a cell in the blood can be carried a long distanc e in just a matter of second s. The body often tries to fight off disease , but white blood cells are one of the body’s defens es and the pathog en can get around or overco me the defens e. Also, someti mes the host (the patient ) maybe in a weak state (sick, malno urishe d, etc.) and unable to effecti vely mount a defens e.

Malari a. A mosqu ito bites a human , infecti ng the human with sporoz oites which are carried by the blood to the liver. The parasit e infects liver cells and grows, killing the cell and releasi ng malari a parasit es into the blood. These infect red & white blood cells, reprod ucing and eventu ally burstin g the blood cells, releasi ng the parasit es which are male and female gamet ocytes. A mosqu ito bites the human , suckin g blood and obtaini ng male and female gamet ocytes. In the gut of the mosqu ito, a male and female gamet ocyte fuse and form the mature form of the parasit e, the zygote. The zygote goes throug h sexual reprod uction formin g sporoz oites which migrat e to the salivar y gland of the mosqu ito. The cycle then contin ues.

Classif ication s, moder n vs. clinica l. In classifi cation, just know that the moder n classifi cation uses the sequen ce of DNA, so that there is no argum ent or subject ivity about what someth ing is classifi ed as. For the parasit es, just learn the clinica l classifi cations .

DNA genetic coding . See the earlier part of Ch. 7.

The diffs betwee n transfo rmatio n, conjug ation, and transd uction. A second student said transd uction.

These are differe nt proces ses that spread around existin g genetic variati on. Look at the picture s to sort them out. Transf ormati on involv es a cells taking in DNA, transd uction involv es movin g DNA around using a virus, and conjug ation is the spreadi ng around of DNA by bacteri al sex. :>)

With the operon , is the RNA polym erase always bound and ready to go or do the attach when the repress or (protei n) drops off? The polym erase can always attach to the promot or DNA and attemp t to move down the DNA. Someti mes it is ready to go and someti mes it will attach after the repress or protein falls off. If the repress or protein is on the operat or, the polym erase will stay blocke d at the operat or for awhile, but if the repress or protein does not come off, the polym erase will eventu ally fall off.

R cell + S dead cell --> Dead mouse, how does the DNA get incorp orated into anothe r organi sm? DNA only gets incorp orated into the R cell, not the mouse. You only need to know that DNA comes out of the heat killed S cells and gets incorp orated into the R cell. What is actuall y happen ing is rather compl ex. DNA comes over to the cell membr ane and either gets inside the cell by recept or- mediat ed endocy tosis or pinocy tosis (bulk phase endocy tosis). The vesicle then either breaks down or release s the DNA into the cytopl asm. The DNA moves to the chrom osome and pairs up to a similar sequen ce of DNA. DNA recom binatio n occurs, and the new DNA becom es inserte d into the chrom osome. The chrom osome then expres ses that DNA just like any other DNA on the chrom osome. This is too detaile d for our class.

Regula tion of gene expres sion. Which are the most import ant parts?

Since they differ, you need to unders tand at least some of both cellula r regulat ion (at the level of the protein ) and genom ic regulat ion (at the level of the gene). For genom ic, know the lac operon .

Why does transfo rmatio n not happen in eukary otes? It does happen in micror ganism s which are eukary otes, such as yeast cells. Micro bes can take up DNA into their cells. Huma ns comin g upon floatin g DNA in a pool will not take it up. It cannot get across our skin.

Ames test is confus ing. Lac operon . Secon d person said the Ames test. Try lookin g at the picture s and see if that helps you make sense of them. Then reread the topics and look at the picture s while you do so.