The scientists(s) who performed experiments with heavy isotopes of nitrogen to prove that DNA replicates semiconservatively is/are
Fredrick Griffith
Watson and Crick
Taylor
Meselson and Stahl
Meselson and Stahl
D.
Meselson and Stahl
Meselson and stahl tested the hypothesis of DNA replication. They cultured bacteria in a 15 N medium. 15 N is a heavy isotope of nitrogen so the DNA synthesized is of heavy density. They then shifted the bacteria to a 14 N medium, DNA was isolated at different times corresponding to replication cycle 0, 1 and 2.
If the four bases of DNA have to code for twenty amino acids, the code should constitute a combination of bases. This was proposed by
Rosalind
Har Gobind Khorana
George Gamow
Marshall Nirenberg
Marshall Nirenberg
Match the following
List I | List II |
A. Contraceptive pill | 1. Prevents sperms reaching the female reproductive tract |
B. Condom | 2. Inhibits ovulation and implantation |
C. Vasectomy | 3. Increases phagocytosis of sperms |
D. Copper I | 4. Blocks gamete transport |
A - 4; B - 1; C - 2; D - 3
A - 1; B - 2; C - 3; D - 4
A - 2; B - 1; C - 3; D - 4
A - 4; B - 3; C - 1; D - 2
A - 4; B - 3; C - 1; D - 2
The natural antibodies in the plasma of a person with blood group 'O' is
Anti- A only
anti - B only
Anti-A and Anti-B only
Anti-B and Anti-D only
Anti-B and Anti-D only
In Eukaryotes, the removal of RNA polymerase III from the nucleoplasm will affect the transcription of
mRNA
hnRNA
tRNA
5.8S rRNA
5.8S rRNA
X and y are disenses in infants. X is produced by deficiency of proteins and calories. Y is produced by protein deficiency unaccompanied by calories deficiency. X and Y are respectively
Kwashiokar; Marasmus
Diabetes; Goitre
Goitre; Diabetes
Marasmus; Kwashiorkar
Marasmus; Kwashiorkar
Which one of the following does not follow the central dogma in molecular biology?
HIV
E.coli
Mucor
Chlamydomonas
Chlamydomonas
Which among these are correctly matched
(i) Down's syndrome - trisomy 21
(ii) Klinefelter's syndrome - 45, XO
(iii) Turner's syndrome - 47x XXY
(ii) and (iii) only
(i) only
(i) and (ii) only
(iii) only
(iii) only
Choose the correct correctly matched pair
CAD - Atherosclerosis
Tetany - Disorder of the neuromuscular junction
Gout - Rapid spasms in muscles
Goitre - Hyperthyroidism
Goitre - Hyperthyroidism