A person affected with phenylketonuria, lacks an enzyme that converts the amino acid phenylalanine into
Valine
Proline
Histidine
Tyrosine
Tyrosine
Identify the wrong statement about DNA
The length of DNA is defined as the number of base pairs present in it
Cytosine is common to both DNA and RNA
In a nucleotide, the nitrogenous base is linked to a phosphate group
Thymine is chemically 5-methyl uracil
Thymine is chemically 5-methyl uracil
Choose the wrong statement
In grasshopper, besides autosomes males have only one X-chromosome, whereas females have a pair of X-chromosomes.
In XY type of sex determination, both males and females have same number of chromosomes.
In Drosophila, males have one X and one Y chromosome, whereas females have a pair of Xchromosome besides autosomes
In birds, females have one Z and one W chromosomes, whereas males have a pair of Z chromosomes besides autosomes
In birds, females have one Z and one W chromosomes, whereas males have a pair of Z chromosomes besides autosomes
C.
In Drosophila, males have one X and one Y chromosome, whereas females have a pair of Xchromosome besides autosomes
XX-XO type of sex determination is found in roundworms and some insects like tree bugs, grasshoppers etc. Here, the females have two sex chromosome XX, while the males have only one sex chromosome X. There is no second sex chromosome. Females show homogamety and produce all X containing eggs while males show heterogamety and produce both X containing sperms and sperms without sex chromosomes.
Which property among these listed below is not a criteria for a molecule to act as a genetic material?
Generate its replica
Chemically and structurally stable
Mutate slowly to facilitate evolution
Express itself in the form of Mendelian characters
Express itself in the form of Mendelian characters
Match Column I with Column II and choose the correct option.
Column I (Scientists) | Column II (Concept) |
I. Taylor and colleagues | A. Lac operon |
II. Hershey and Chase | B. DNA replicates semi-conservatively |
III. Griffith | C. Transforming principle |
IV. Jacob & Monod |
D. DNA is the genetic material E. Transcription |
I - B; II - E; III - A; IV - C
I - C; II - D; III - B; IV - A
I - B; II - D; III - C; IV - A
I - A; II - E; III - D; IV - B
I - A; II - E; III - D; IV - B
In sickle cell anemia, the sequence of amino acids from the first to the seventh position of the b-chain of haemoglobin S(HbS) is
His, Leu, Thr, Pro, Glu, Val, Val
Val, His, Leu, Thr, Pro, Glu, Glu
Thr, His, Pro, Val, Pro, Val, Glu
Glu, His, Leu, Pro, Val, Glu, Glu
Glu, His, Leu, Pro, Val, Glu, Glu
Read the following statements and choose the correct option:
I. RNA polymerase associates transiently with 'Rho' factor to initiate transcription.
II. In bacteria, transcription and translation takes place in the same compartment.
III. RNA polymerase I is responsible for transcription of tRNA.
IV. When hnRNA undergoes capping process, adenlyte residues are added at 3' end in a template independent manner.
V. hRNA is the precursor of mRNA.
II only is correct
II, III and V only are correct
III and IV only are correct
I and IV only are correct
I and IV only are correct
Choose the correct statement.
Haploid content of human DNA is 4.6 × 106 bp.
A nitrogenous base is linked to pentose sugar through phosphodiester linkage
X-ray diffraction data of Maurice Wilkins and Rosalind Franklin was the basis of Watson and Crick's DNA model
DNA is an acidic substance was first identified by Watson and Crick
DNA is an acidic substance was first identified by Watson and Crick
Aminoacylation of tRNA is essential for
replication of RNA
formation of peptide bond
splicing
initiation of transcription
initiation of transcription