Molecular Basis of Inheritance Test

Result

Molecular Basis of Inheritance Test - 57

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

Melting temperature for double stranded molecules are converted into single stranded molecules. Which one of the following DNA will have the highest melting temperature?

A
DNA with $$15$$% guanine

B
DNA with $$30$$% cytosine

C
DNA with $$40$$% Thymine

D
DNa with $$50$$% adenine

Solution

The stability of the DNA segment depends on the type of bases. If the DNA is rich in cytosine and guanine, then the DNA is considered to be more stable and have the highest melting point. The more the number of cytosine and guanine, the more are the hydrogen bonds and more stable is the DNA.
Thus, the correct answer is option B.
Question 2
1 / -0

Transfer RNA (tRNA)

A
Is present in the ribosomes and provides structural integrity

B
Usually has clover leaf-like structure

C
Carries genetic information from DNA to ribosomes

D
Codes for proteins

Solution

The molecular structure of T -Rna can be explained by a cloverleaf model which was proposed by Holley. According to this model, a single polynucleotide chain is folded upon itself to due to which 3' and 5' end come close to each other and the 3' end has CCA nucleotides and G at the fifth end. This model shows the presence of three arms namely DHU arm, a middle arm, TPsi C arm. These arms have loops at their terminal end such as aminoacyl loop, anticodon loop, ribosomal binding loop. It also shows the presence of small lump called as a variable lobe or extra arm. Thus the correct answer is option B.
Question 3
1 / -0

In a random DNA sequence, what is the lowest frequency of encountering a stop condon?

A
$$1$$ in $$20$$

B
$$1$$ in $$3$$

C
$$1$$ in $$64$$

D
$$1$$ in $$10$$

Solution

UAA, UAG and UGA are stop codons. These stop codons signal the termination of translation which is the process of protein synthesis. In a random DNA sequence stop codons occur at a frequency of around 1 in 20. Thus the correct answer is option A.
Question 4
1 / -0

Desert temperature often varies between 0 to 50$$^o$$C. The DNA polymerase isolated from a camel living in the desert will be able to synthesize DNA most efficiently at

A
$$0^o C $$

B
$$37^o C $$

C
$$50^o C $$

D
$$25^o C $$

Solution

The camels are the dessert animals which belong to the group of mammals. The mammals are able to maintain the temperature of the body constant. The body temperature is maintained optimum at 37$$^o$$ C and this is the temperature at which all the reactions takes place with the optimum activity of the enzymes. So, the enzyme DNA polymerase will synthesize the DNA most effectively at this temperature.
Thus, the correct answer is option B.
Question 5
1 / -0

Watson and Crick model of DNA is a

A
$$B$$-form DNA with a spiral length of $$34 \mathring { A } $$ and a diameter of $$20 \mathring { A } $$

B
$$A$$-form DNA with a spiral length of $$15 \mathring { A } $$ and a diameter of $$20 \mathring { A } $$

C
$$Z$$-form DNA with a spiral length of $$34 \mathring { A } $$ and a diameter of $$20 \mathring { A } $$

D
$$B$$-form DNA with a spiral length of $$28 \mathring { A } $$ and a diameter of $$14 \mathring { A } $$
Solution
- The model of DNA was given by Watson and Crick in the year 1953. It is the hereditary molecules that are responsible for carrying the characters from parents to offspring.
- The DNA is in the $$B$$-form that shows left-handed coiling.
- The spiral length is $$34 \mathring { A } $$ and its diameter of $$20 \mathring { A } $$. One spiral turn has $$10$$ base pairs.
  Thus the correct answer is option A.
Question 6
1 / -0

A new life from discovered on a distant has a genetic code consisting of five unique nucleotides and only one stop codon. If each codon has four bases, what is the maximum number of unique amino acids this life from can use?

A
$$624$$

B
$$20$$

C
$$124$$

D
$$3124$$

Solution

As it is given in the question each codon has four bases, As the new life form has five unique nucleotides there are 5 possible combinations for the first position in the codon. This is repeated for all codons. As there are 4 codons using probability 5x5x5x5= 625 which can be approximated to 624. Thus the correct answer is option A.
Question 7
1 / -0

According to the original model of DNA, as proposed by Watson and Crick in 1953. DNA is a

A
Right handed helix

B
Helix that makes a full turn every 70 nm

C
Helix where one turn of DNA contains 20 basepairs

D
Two stranded helix where each strand has same polarity
Solution
- The model of DNA was given by Watson and Crick in the year 1953. It is the hereditary molecules that are responsible for carrying the characters from parents to offspring.
- The DNA is in the $$B$$-form that shows right-handed coiling. The spiral length is $$34 \mathring { A } $$ and its diameter of $$20 \mathring { A } $$. One spiral turn has 10 base pairs.
- Thus, the correct answer is option A.
Question 8
1 / -0

During replication of DNA, the two strands of the double helix are separated from each other under the influence of enzyme

A
Rep-protein

B
SSBP

C
Initiator protein

D
DNA polymerase

Solution

Rep protein is the repetitive extragenic palindromic protein that serves to unwind the DNA to initiate the replication. SSB proteins serve to stabilise the unwound DNA by preventing the formation of H-bonds between the base pairs of the ssDNA. DNA polymerase elongates the primer by addition of deoxyribonucleotides. Initiator proteins serve to recognise the ori followed by formation of primosome.
So, the correct answer is option A.
Question 9
1 / -0

A phenomenon where the third base of t-RNA at its 5' end can pair with a complementary base of m-RNA is called

A
Degenerency

B
Wobbling

C
Universality

D
Colinearity

Solution

The genetic code is degenerate which means that one codon can specify more than one amino acid. For example, GAA and GAG both specify same amino acid which is glutamic acid and not any other amino acid. Degenerate codons differ in their third positions.
There are 64 codons and only 20 amino acids. Due to this the redundant codons which specify the same amino acid are related to each other by a sequence. For example, leucine is specified by codons CUU, CUA, CUC and CUG. All the codons are same except the ones at third position. The third position is known as wobble position which can change but still specify the same amino acid.
Genetic code is universal which means that it is same for all organisms raging from bacteria to man except certain bacteria, mitochondria and protists where minor variations can be seen.
Genetic code is collinear which means that the sequence of amino acids in a polypeptide chain corresponds to the sequence of bases in DNA that codes for it. Any change in codon will change the amino acid in polypeptide.
Thus, the correct answer is option A.
Question 10
1 / -0

There are 64 codons in the genetic dictionary as

A
There are 64 amino acids to be coded

B
Genetic code has a triplet nature

C
There are 3 nonsense codons and 61 sense codons

D
There are 64 different types of t-RNA

Solution

There are 64 colons as genetic code is triplet. Three adjacent bases, termed a codon specify one amino acid. This can only account for the 20 amino acids. Thus in a triplet codon, the four bases would specify a total of 64 amino acids. Thus, the correct answer is option B.

User

Question Analysis

Correct -
Wrong -
Skipped -

My Perfomance

Score
-
out of -
Rank
-
out of -

Re-Attempt Weekly Quiz Competition

Molecular Basis of Inheritance Test - 57

Result

Molecular Basis of Inheritance Test - 57

Score

-

Rank

-

SHARING IS CARING

Question 1

DNA with $$15$$% guanine

DNA with $$30$$% cytosine

DNA with $$40$$% Thymine

DNa with $$50$$% adenine

Solution

Question 2

Is present in the ribosomes and provides structural integrity

Usually has clover leaf-like structure

Carries genetic information from DNA to ribosomes

Codes for proteins

Solution

Question 3

$$1$$ in $$20$$

$$1$$ in $$3$$

$$1$$ in $$64$$

$$1$$ in $$10$$

Solution

Question 4

$$0^o C $$

$$37^o C $$

$$50^o C $$

$$25^o C $$

Solution

Question 5

$$B$$-form DNA with a spiral length of $$34 \mathring { A } $$ and a diameter of $$20 \mathring { A } $$

$$A$$-form DNA with a spiral length of $$15 \mathring { A } $$ and a diameter of $$20 \mathring { A } $$

$$Z$$-form DNA with a spiral length of $$34 \mathring { A } $$ and a diameter of $$20 \mathring { A } $$

$$B$$-form DNA with a spiral length of $$28 \mathring { A } $$ and a diameter of $$14 \mathring { A } $$

Solution

Question 6

$$624$$

$$20$$

$$124$$

$$3124$$

Solution

Question 7

Right handed helix

Helix that makes a full turn every 70 nm

Helix where one turn of DNA contains 20 basepairs

Two stranded helix where each strand has same polarity

Solution

Question 8

Rep-protein

SSBP

Initiator protein

DNA polymerase

Solution

Question 9

Degenerency

Wobbling

Universality

Colinearity

Solution

Question 10

There are 64 amino acids to be coded

Genetic code has a triplet nature

There are 3 nonsense codons and 61 sense codons

There are 64 different types of t-RNA

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.