Molecular Basis of Inheritance Test

Result

Molecular Basis of Inheritance Test - 93

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

The deflection of pitch angle between two successive steps (rungs) of DNA is

A
$$72^{\circ}$$

B
$$54^{\circ}$$

C
$$36^{\circ}$$

D
$$18^{\circ}$$

Solution

The twist of a DNA double helix corresponds to the angular rotation that is needed to get from one base pair to the next. In an idealized DNA molecule the twist is 36 degrees, meaning that if you rotate one base pair by 36 degrees and move it up the helix by 0.34 nm, you will occupy the position of the next base pair. Thus, the distance or rise along the axis of the double helix is 0.34 nm between 2 consecutive base pairs.
Question 2
1 / -0

A terminator codon which is called amber is

A
UGA

B
UAG

C
UAA

D
UUU

Solution

There are three codons UAA, UAG and UGA which signals the termination of the synthesis of a protein.
UAG is amber
UGA is opal
UAA is ochre.
Thus, the correct answer is option (B).
Question 3
1 / -0

The nucleotide sequence on antisense strand of DNA which is transcribed as codon that specifies the amino acid serine is

A
TCA

B
AGU

C
TAC

D
CCC

Solution

The template DNA strand that serves in RNA synthesis during transcription is called anticoding or antisense strand, while the other strand is called coding or sense strand of its base sequence, is same as that of newly synthesized mRNA. Thus, the antisense strand has the complementary sequence to its corresponding mRNA and the mRNA codons UCA, UCG, UCU, UCC, AGU and AGC code for serine; the corresponding DNA codons AGT, AGC, AGA, AGG, TCA and TCG will code for serine; option A is the correct answer. Option B is incorrect as base “uracil” is not found in DNA. Options C and D are incorrect as the DNA codons TAC and CCC will code for AUG and GGG in the corresponding mRNA which in turn code for methionine and glycine respectively.
Question 4
1 / -0

What will be the codons in m-RNA if the DNA codes are ATG-CAG?

A
TAC-GTC

B
UAC-GUC

C
UCA-TUA

D
TCA-GTC

Solution

We know that Thymine (T) always pairs with adenine (A) and Guanine (G) with cytosine (C). RNA has uracil (U) in place of thymine therefore; adenine pairs with uracil in RNA. So, the mRNA codon for ATG-CAG code will be UAC-GUC which makes option B correct.
Options A, C and D are incorrect as thymine is absent in RNA and the sequences in these options do not follow the complementary base pairing mentioned.
Therefore, the correct answer is option B.
Question 5
1 / -0

Out of A-T, G-C pairing, bases of DNA may exist in alternate valency state owing to arrangement called as

A
Tautomerisational mutation

B
Analogue substitution

C
Point mutation

D
Frameshift mutation

Solution

Nitrogen bases are aromatic cyclic ketones with amine or imine group. Tautomers are a type of structural isomers which are formed by shifting of pi-bonds between functional groups. They are also called as keto-enol isomers and are inter-convertible into each other as “-C=C-C-OH” change to “C-C-C=O” . Tautomerization converts the amino (-NH2) group of cytosine and adenine into amino (-NH) group and keto (C=0) of thymine and guanine into enol group (-OH). This results in the pairing of tautomeric thymine with normal guanine and of cytosine with adenine. The resultant mutation is caused by tautomeric mutations. Thus, the correct answer is option A.
Question 6
1 / -0

When DNA replication starts

A
The leading strand produces Okazaki fragments.

B
The hydrogen bonds between the nucleotides of two strands break.

C
The phosphodiester bonds between the adjacent nucleotides break.

D
The bonds between the nitrogen base and deoxyribose sugar break.

Solution

Okazaki fragments are produced on lagging strand. DNA replication starts with unwinding of DNA duplexes which are held together by hydrogen bond. Helicases move along the double stranded DNA and separate the strands by breaking hydrogen bonds between base pairs. ATP hydrolysis provides the required energy for breaking of hydrogen bonds. DNA polymerase enzyme adds deoxyribonucleotides to primer by formation of phosphodiester bond betweenbetween the 3' oxygen of a growing strand and alpha phosphate of a dNTP. Breaking of bond between nitrogen base and deoxyribose sugar is part of nucleotide catabolism; it does not occurs during DNA replication. Thus, the correct answer is option B.
Question 7
1 / -0

From the given genetic code table, find out the 1$$^s$$$$^t$$ and last amino acid formed from the mRNA associated with the given DNA template strand.

A
Ala and stop codon

B
Arg and Cyst

C
Arg and stop codon

D
Ala and Trp

E
Tyr and Thr

Solution

The sequence of mRNA is complementary to that of the DNA template strand. Hence, the mRNA of given DNA strand will have the following sequence: 3’CGC UGU AUG UGA 5’. Hence, the first and last amino acid will be arginine (CGC) and stop codon (UGA).
Therefore, the correct answer is option C.
Question 8
1 / -0

E. coli bacteria grew in a nutrient solution containing a heavy, stable isotope of nitrogen, $$^{15 }N$$. It is then transferred to a medium with the more common light isotope of nitrogen. Then DNA from the cells was extracted and subjected to density centrifugation. The strain of E. coli used to divides once every 20 minutes. The results are illustrated below, the heaviest DNA is extracted from the cells at

A
0 minutes

B
20 minutes

C
40 minutes

D
60 minutes

E
40 and 60 minutes
Question 9
1 / -0

An error in the polypeptide chain produced from DNA sequence is not always the result of mutation. The best explanation for this is that

A
Some polypeptides are produced by a code other than a nucleic acid code

B
The nucleolus can repair damaged DNA

C
The Golgi body can repair damaged DNA

D
Different codons code for the same amino acid

E
Scientists have no idea why this phenomenon occurs

Solution

A mutation causing the no change in the amino acid and hence no effect on the function of the protein is called as a silent mutation. If point mutation alters the base of a codon in such a way that the altered codon also codes for same amino acid; the will not be any mutation. This is due to the degeneracy of genetic code that allows one amino acid to be encoded by multiple codons. The correct answer is D.
Question 10
1 / -0

Which of the following is true about codon?

A
A group of three nucleotide sequences

B
The nucleotide units between the start and stop codes

C
The nucleotide sequence that serves as the instructions for a protein

D
A single nucleotide in an mRNA sequence

E
The sequence of nucleotides that signals the start or stop of protein sythesis

Solution

A set of three nucleotides serve as a codon that specify an amino acid. for example, the mRNA codon "ACU" codes for threonine, irrespective of its source. A nucleotide sequence that serves as instruction for protein is mRNA and have multiple genetic codons between start and stop codons.
Therefore, the correct answer is option A.

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Molecular Basis of Inheritance Test - 93

Result

Molecular Basis of Inheritance Test - 93

Score

-

Rank

-

SHARING IS CARING

Question 1

$$72^{\circ}$$

$$54^{\circ}$$

$$36^{\circ}$$

$$18^{\circ}$$

Solution

Question 2

UGA

UAG

UAA

UUU

Solution

Question 3

TCA

AGU

TAC

CCC

Solution

Question 4

TAC-GTC

UAC-GUC

UCA-TUA

TCA-GTC

Solution

Question 5

Tautomerisational mutation

Analogue substitution

Point mutation

Frameshift mutation

Solution

Question 6

The leading strand produces Okazaki fragments.

The hydrogen bonds between the nucleotides of two strands break.

The phosphodiester bonds between the adjacent nucleotides break.

The bonds between the nitrogen base and deoxyribose sugar break.

Solution

Question 7

Ala and stop codon

Arg and Cyst

Arg and stop codon

Ala and Trp

Tyr and Thr

Solution

Question 8

0 minutes

20 minutes

40 minutes

60 minutes

40 and 60 minutes

Question 9

Some polypeptides are produced by a code other than a nucleic acid code

The nucleolus can repair damaged DNA

The Golgi body can repair damaged DNA

Different codons code for the same amino acid

Scientists have no idea why this phenomenon occurs

Solution

Question 10

A group of three nucleotide sequences

The nucleotide units between the start and stop codes

The nucleotide sequence that serves as the instructions for a protein

A single nucleotide in an mRNA sequence

The sequence of nucleotides that signals the start or stop of protein sythesis

Solution

User

Question Analysis

My Perfomance

Score

-

Rank

-

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.