600N DNK ni 1 ta ipi yoki i-RNK
dagi N lar
Javob: D _____________________________ 240. Oqsil zanjirining molekulyar massasi 12000. Bitta
aminokislotaning o‘rtacha massasi 120 ga teng. Qo‘shni nukleotidlar
orasidagi masofa 0,34 nm bo’lsa, quyidagilarni aniqlang.
a) genning uzunligi (nm); b) DNK qo‘sh zanjiridagi nukleotidlar
soni; c) i-RNKdagi nukleotidlar soni; d) purin va pirimidin
asoslarining o‘zaro nisbati;
1) 102; 2) 34; 3) 4000; 4) 600; 5) 100; 6) 300; 7) 120; 8) 1:1; 9)
1:3; 10) 1:2
A) a-1; b-4; c-7; d-10
B) a-1; b-4; c-6; d-8 C) a-3; b-7; c-4; d-10 D) a-2; b-5; c-6; d-9
Ishlanishi: 1) 12000/120=100AK; 100*3=300N
a) L=300*0,34=
102nm ; b) 300*2=
600N ;
c) i-RNK da-
300N ; d)
1:1 Javob: B _____________________________ 241. DNK molekulasida adenin va timin nukleotidlari orasida
ikkita, guanin va sitozin nukleotidlari orasida uchta vodorod bog’i
borligi ma’lum. DNK fragmentida 1040 ta vodorod bog’i bo’lib,
ushbu fragmentda adenin nukleotidlari umumiy nukleotidlarning
20% ini tashkil etsa, ushbu molekuladagi jami nukleotidlar sonini
aniqlang.
A) 810
B) 800 C) 1000 D) 832
Ishlanishi: 1) A-20%=20%-T 40%-A+T 100-40=60%
60:2=30%-G-S
2) 30/20=1,5 G=1,5A
3) 2A+3G=H => 2A+3*1,5A=1040
2A+4,5A=1040 6,5A=1040 A=160
4) 2*160+3G=1040
3G=1040-320 3G=720 G=240
5) (A+G)*2=(160+240)*2=400*2=
800N Javob: B _____________________________ 242. DNK ning qo‘sh zanjirida G nukleotidlari 40% ni tashkil
etadi. DNK dagi gen asosida sintezlangan oqsil 400 ta
aminokislotadan iborat bo‘lsa, shu DNK qo'sh zanjiridagi guanin va
sitozin orasidagi vodorod bog'lari sonini toping.
