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+--- Thread: I am also weak in Beh. & Genteics - drfuture (/showthread.php?tid=669593)
0 - ArchivalUser - 04-09-2012
@hd12
Q6 coorect anser is B
Clinitest is a nonspecefic test positive with glucose,fructose and galactose.
In contrast, urine dipstick is only positive for glucose
so with a urine dipstick we can not exclude presence of galactose and fructose then we need to do a clinitest to check for that
Q7 anser is A+D tyrosine is essential in patients with PKU and dihydrpteriorate reductase deff. *** ( sorry I did not write deff. ) this DHB reductase enz is needed for proper function of phenylalanine hydroxylase
thanks for ur contribution Q8 answer is BB
loss a an amino acid mean loss of 3 nucleotides and this is called In-frame mutation whic is less grave than frame shift mutation seen in Familial hypercholesterolemia and Duchene ms. dystrophy
feel free for further discussion
0 - ArchivalUser - 04-09-2012
Probability of GETTING a difference when there IS a difference IS CALLED:
a. Alpha
b. Beta
c. 1-Beta
d. Type 1 Error
e. Type 2 Error
f. Coeffecient of determination
0 - ArchivalUser - 04-09-2012
ccc
0 - ArchivalUser - 04-09-2012
Correct 1-B = POWER OF STUDY
0 - ArchivalUser - 04-09-2012
Q. what effect does lowering of alpha level have on the power of the study?
increase
decrease
0 - ArchivalUser - 04-09-2012
a. probability of GETTING a difference when in fact there is no difference TYPE1ERR
b. '''''''''''''''''''''''''''GETTING NO difference '''''''''''''''''''''''''''''is a difference TYPE2ERR
0 - ArchivalUser - 04-09-2012
In the question about lac operon in presece of glucose and lactose
Is going to break lactose depending in the amount of glucosa present.
If there is more lactose and a little amount of glucosa, the lac operon is going to be able to break lactose. If is glucose more than lactose, the bacteria is going to use off course glucosa like a major fuel.
Kaplan 2004 page 71
Coordinate control of the lactose operon by glucose and lactose
Full expression of the lactose operon requieres both mechanisms favor gene expression
- The represor protein must not bind at the operator and
- The cAMP dependent activator protein must bind to the CAP site.
This in turn requieres that:
- Lactose is present (prevents repressor binding)
- Glucose is low (to allow cAMP to increase)
It is convenient to simplify the situation in the following way:
The only condition that allows high gene expression is : lactose present, glucose absent.
All other combinations of these sugars result in low level expression.
0 - ArchivalUser - 04-09-2012
thank drcvx
0 - ArchivalUser - 04-09-2012
99% confidence interval
means that we have a higher SEM cuz CI= MEAN +- SEMxZ score
and that means less precesion and consistency in our means.
but in the mean time it is more accurate cuz the mean we have is more likely to be present with in a large ranger than with in a narrower range
0 - ArchivalUser - 04-10-2012
Q10 A 21 yo male patient presents to u with eunuchoid habitus, tall extremeties, gynecomastia, female hair distribution and infertility. what is the best diagnostic test?
a. Karyotyping at anaphase
b. karytyping at metaphase
c. RFLP studies
d. ASO probes
e. Sequencing
f. Karytyping during meiosisII
Q11 In the aforementioned question what is the most likely causative genetic defect during gametogenesis in this individual:
a. nondysjunction of sex chromosome at meiosis I
b. nondysjunction of autosomes at meiosis I
c. nondysjunction of autosomes at meiosis II
d. nondysjunction of sex chromosome at meiosis II