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DrVirgo
Forum Junior  Topics: 731 Posts: 3487 |
See picture... Choices: A. 100 B. 50 C. 33 D. 25 E. 0 (%) PLEASE EXPLAIN!! 
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muzammil
| Forum Guru  Topics: 17 Posts: 681
wher is the pic
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DrVirgo
| Forum Junior Topics: 731 Posts: 3487
.here is the pic... sorry it didn't attach first time. Attached Files: Genetics.JPG (42 KB, 186 downloads)
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robin082006
| Forum Hero  Topics: 468 Posts: 5028
A. 100%
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DrVirgo
| Forum Junior Topics: 731 Posts: 3487
no. not A
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robin082006
| Forum Hero Topics: 468 Posts: 5028
E???????
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Cedrick
| Life  Topics: 0 Posts: 1425
D if is ressesive 25%
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Cedrick
| Life Topics: 0 Posts: 1425
If is autosomic DOMINANT is 50% if is autosimic Ressesive is 25 %
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DrVirgo
| Forum Junior Topics: 731 Posts: 3487
E is right... can you explain Robin?
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Cedrick
| Life Topics: 0 Posts: 1425
yes please
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Cedrick
| Life Topics: 0 Posts: 1425
It does not matter to me thanks for the post gang
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robin082006
| Forum Hero Topics: 468 Posts: 5028
look III3 and III4 Both are males and receive X chromosome from their mother. Both are phenotypically normal so their X chromosome is normal--> upper X chromosomes is normal. II4 is father, has one X normal. III 2 recieves one normal X from father and the normal other from mother. she carries both normal X--> 0% at first I only looked at father and though lower X is noraml and the upper one is abnormal. I should be careful for such question
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Cedrick
| Life Topics: 0 Posts: 1425
tricky one
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DrVirgo
| Forum Junior Topics: 731 Posts: 3487
Thanks... I figured it out by the pedigree only... You don't need the info withthe bands to solve it, right?
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study_ing
| Forum Fanatic  Topics: 179 Posts: 2261
U do...to figure out that the alleles in the 2 normal sons are differentand hence BOTH are normal. if the bands werent there , we'd have to calculate risk of being a carrier etc
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DrVirgo
| Forum Junior Topics: 731 Posts: 3487
yes i see it now... II-5 has two normal X's so her kids are normal.
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mediocre
| Forum Elite Topics: 37 Posts: 225
hello, I am finding it tough to understand the qs especially the box with dashes and roman numerals,forgive me for sounding like a lay man ,I think step1 will force me to come face to face with all the nightmares i avoided back in medical school......gulp!!, so please can any one spoon feed me.....thanx! 
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mediocre
| Forum Elite Topics: 37 Posts: 225
.....well I guess I figured it out after some cool thinking,sorry 4 the trouble guys ,I get scared early,and 4 those who r as repulsive of genetics as i m let me decipher the facts to help others,here goes..(only 4 mediocres!!) ii4,ii5------------are just the labels (x,y axis)for dad and mom of the woman concerned(shown with an arrow) the bars in the box are genetic mapping of the x chromosomes of men and women ,hence only one bar for a male and two for femal to show the distribution of different x chromosomes of the mother since there is a chance that the same x chromosome might have been reused in both iii3 and iii4 as studying pointed out. THE PEDIGREE is an XR as no females are diseased. in an XR carrier mother atleastr50% of her son has to be affected which is not a case here so ii-5 is innocent,not a carrier,ie has no defective X to give to her daughter which may accept one of her x chromosome ,the other X comes from her father who is normal so cant have defective X (no carriers possible in males,eithr dsd or normal) so the iii-2 female is proved not to be a carrier . QID 
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