Jump to content

Paul Atreides

Members
  • Posts

    6
  • Joined

  • Last visited

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

Paul Atreides's Achievements

Lepton

Lepton (1/13)

1

Reputation

  1. Hello scientific enthusiasts! I have recently been studying the ultrastructure of the cell particularly with endoplasmic reticuli. I understand that this classification of organelles is divided into the soft and rough groups which have their respective functions of cell detoxification, lipid synthesis and so forth. But according to several comparison charts in biology books and online resource websites endoplasmic reticuli are stating as being rarely absent in eukaryotic cells. However, the part about them being rarely absent is not explained. Therefore, I would be much obliged if someone could explain to me under what circumstances these organelles are absent from eukaryotic cells.
  2. It largely depends on whether you find the course description of genetics at Clemson University (I am guessing you are in South Carolina?) to be engaging and whether you have the funds to be able to study at that university. If you have good grades then what is important in this case is that you choose a university that offers a genetics degree that you find interesting and that you could be passionate about by inspecting what subjects they take you through and whether your expectations would be met. In this case, you have to carry out some reading of your own time of university websites or their prospectuses. As I do not live in South Carolina, I do not know which educational institution would be best to join. You should have a talk with the respective heads of the departments, since you are there physically, to gain a better picture of the selection you have and whether you or your parents can afford the fees. Afterall, this is your education so you should take the time to analyse your choices as the university you enter can have ramifications (either good or bad) for the rest of your life. If you are looking for places that are prestigious, be warned that they may be resting on their laurels and thereby may offer a bad learning experience in the long term. Institutions that are lower in raking could be better as they must prove themselves to improve their status but please keep in mind that academic rankings are not always clean, as there are scandals where universities bribe ranking organisations to get ahead.
  3. Dear all, I think I have found the solution to my problem. Firstly, the sodium-potassium coefficient is not Na+1/K+1 but rather PNa/PK. From then on, it is a simple case of multiplying the numerator and the denominator of the original equation by 1/PK. Thus, the following steps are obtained where PNa/PK can be represented by the arbitrary variable "a" to simplify when solving: E = RT/F * ln((PNa[Na+]o + PK[K+]o)/(PNa[Na+]i + PK[K+]i)) E = RT/F * ln((PNa[Na+]o * 1/PK + PK[K+]o * 1/PK)/(PNa[Na+]i * 1/PK + PK[K+]i * 1/PK)) E = RT/F * ln((PNa/PK[Na+]o + [K+]o)/(PNa/PK[Na+]i + [K+]i)) E = RT/F * ln((a[Na+]o + [K+]o)/(a[Na+]i + [K+]i))
  4. Yeast do indeed store energy in a similar way to other fungi as well as plants. They have food vacuoles that store oils and the sugar glucose in the form of glycogen that can be hydrolysed when needed. It is indeed impossible for yeast to respire without an energy source, let alone any other organism, but if they have stored energy then it is possible. Lastly, using sink water wouldn't matter that much unless you have a very shady water company that pumps water to users with glucose dissolved. Tap water generally contains ions or very small amounts of disinfectants which are not of great use energy-consumption wise to many organisms, and in fact some solutes in tap water can even be toxic to micro-organisms such as chlorine or chloride. I hope this answers your question.
  5. Are you sure that ammonia is produced from these bacterial colonies? From my reading, it seems that bacteria do not produce ammonia rather they consume it and produce nitrates that give a sharp-acidic smell (pungent, in other words) that may be confused as ammonia. The class of bacteria you have examined are therefore nitrifying bacteria, but I am having trouble trying to identify which sub-class of bacteria you are trying to view. It would be more helpful if you could provide information on how you obtained these colonies and what growth medium you used (also, did you use any colorimetric methods?), as it is common knowledge that the growth medium can have an effect on the colour of the colonies e.g. mannitol salts agar when fermented give yellow colonies. I had found a few possible suspects, but they are lacking in certain ways based on the descriptions you had given. The colonies best fit the descriptions of the genus Nitrosomonas, but this genus is mostly composed of gram-negative not gram-positive bacteria.
  6. Hello everyone. I have been steadily reading through a book on human physiology and I have come across a problem related to the Goldman Equation that I am trying to understand, which is the following: Because of the fact that we are working with a chloride-free medium, chloride ions are ignored from the Goldman Equation which gives the following: Where E is the membrane potential, RT/F is a constant that is equal to 26.7 at 37 degrees Celsius, P with respective subscripts represent coefficients of different ions, and the ions in square brackets are the concentrations in mmol/L. Subscripts "o" and "i" represent extracellular and intracellular concentrations respectively. Intracellular Sodium Ion Concentration = 20 mmol/L Extracellular Sodium Ion Concentration = 145 mmol/L Intracellular Potassium Ion Concentration = 150 mmol/L Extracellular Potassium Ion Concentration = 4 mmol/L I understand that in order to answer this question I need to show that the membrane potential for the sodium-potassium ion coefficient (Na+1/K+1) is higher at +30 mV than to -90 mV to illustrate that the membrane will be more permeable to sodium during the action potential since +30 mV is closer to the equilibrium potential of sodium at +53 mV and vice versa for potassium. But the solution given is the following: I understand most of the substitutions that take place, except I do not understand how the Goldman Equation is transformed into the solution equation for one membrane potential. Therefore, I would be much obliged if someone could indicate to me how it was accomplished.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.