Biomolecules Test

Result

Biomolecules Test - 53

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 most accepted nitrogen base composition for double stranded DNA is ____________.

A
31% A, 19% T, 31% C, 19%G

B
36% A, 36% U, 24% C, 24%G

C
48% A, 48% T, 52% C, 52%G

D
31% A, 31% T, 19% C, 19%G

E
24% A, 24% U, 36% C, 36%G

Solution

DNA base pairs are of 4types which together gives a ladder form of structure. Adenine with Thymine and Guanine with Cytosine together pairs up with each other.Adenine is 31% then Thymine is also 31%,then Cytosine is (50-31=19%), Guanine is also 19%.
So,the correct option is 'D'.
Question 2
1 / -0

What would be the percentage of thymine (T) and cytosine (C) in a molecule of DNA composed of approximately 16.2% adenine (A) and 33.4% guanine (G)?

A
16.3% T and 16.3% C

B
34.1% T and 34.1% C

C
34.1% T and 16.3% C

D
16.3% T and 34.1% C

E
33.4% T and 16.2% C

Solution

The purine adenine (A) always pairs with the pyrimidine thymine (T) and the pyrimidine cytosine (C) always pairs with the purine guanine (G). These base pair relationships are often called Chargaff's rules of DNA base pairing.
As, A = T and C = G, hence answer is '16.3% T and 34.1% C'
Question 3
1 / -0

Identify the correct order of the size of the structures from the smallest to the largest.
I= Bacterium
II= Enzyme
III= Nucleus
IV= Chromosome
V= Molecule of water

A
V- II- I- IV- III

B
II- V- IV- I- III

C
V- I- II- III- IV

D
II- V- I- IV- III

E
II-V-IV-III

Solution

A water molecule has two hydrogen and one oxygen atom and is smallest among the given options. An enzyme can be as small as a chain of 60 amino acid residues, while a bacterium ranges in 1 micrometre in diameter. The chromosome contains linear DNA molecule which is 2 m long. Nucleus diameter is 6 micrometers. The correct ascending order of size is water molecule, enzyme, bacterium, chromosome and nucleus.
So, the correct answer is option A.
Question 4
1 / -0

Which reactions usually release energy that is used to drive chemical reactions.

A
Anabolic

B
Catabolic

C
Photosynthesis

D
None of the above

Solution

Metabolism refers to series of reactions wherein product of one reaction becomes reactant for the next one. It includes catabolism (degradative pathways) and anabolism (synthetic pathways). Catabolic reactions are the reactions in which complex molecules are broken down into smaller simpler molecules. The catabolic reactions are exergonic reactions( energy releasing reactions). While photosynthesis is an anabolic reaction which requires energy for the formation of complex molecules. Hence option B is the correct answer.
Question 5
1 / -0

Synthesis is a term that could be used synonymously with

A
Metabolism

B
Anabolism

C
Catabolism

D
Dehydration

Solution

Anabolism term refers to the synthesis of complex molecules from simpler ones. The anabolic reaction requires energy hence are endergonic in nature. For example, synthesis of proteins from amino acids, or synthesis of glycogen molecules from simpler glucose molecules. Hence option B is the correct answer.
Question 6
1 / -0

Which of the following element is present in all amino acids and absent in carbohydrates?

A
Sulphur

B
Carbon

C
Oxygen

D
Hydrogen

E
Nitrogen

Solution

Option E is correct.
In amino acids Nitrogen is the Major element that is present. Amino acids are compounds containing carbon, hydrogen, oxygen, and nitrogen. Whereas carbohydrates are compounds containing $$CHO$$, which includes carbon, hydrogen and oxygen.
Question 7
1 / -0

Biochemical reactions are carried out by enzymes

A
By decreasing the energy of the reactants

B
By increasing the activation energy of the reaction

C
By decreasing the activation energy of the reaction

D
By increasing the energy of the products of the reaction

E
By decreasing the energy of the products of the reaction

Solution

Any chemical reaction includes the formation of transition state between reactant and product. The energy required for formation of the transition state is termed as activation energy. Enzymes enhance the rate of reaction by lowering down the activation energy of transition state. Thus, the correct answer is option C.
Question 8
1 / -0

Which molecule binds to uracil in RNA?

A
Thymine

B
Guanine

C
Cytosine

D
Adenine

E
Uracil

Solution

Nitrogenous bases are adenine, guanine, cytosine, and thymine in DNA. One of the chemical differences between DNA and RNA is that in RNA, the nitrogenous base uracil is used instead of thymine. Nitrogenous bases can form hydrogen bonds. Adenine, thymine, and uracil can form two hydrogen bonds. Guanine and cytosine can form three hydrogen bonds. In nucleic acids (DNA and RNA), nitrogenous bases can bind to each other by hydrogen bonding. Guanine binds to cytosine, and cytosine binds to guanine. In DNA, adenine binds to thymine. In RNA, adenine binds to uracil.
Question 9
1 / -0

This graph shows the activation energy required for a certain biochemical reaction to take place. The effect of an enzyme on the same biochemical reaction is shown by

A

B

C

D

E

Solution

Activation energy, is the energy required by all biochemical reactions to occur. In other words, it is the minimum energy that must be available in a system for a chemical reaction to take place. Enzymes are biological catalyst, which helps to increases the rate of reaction without being consumed by it.but lowers the activation energy. However, it does not change the energies of the original reactants or products but lowers the energy required to reach the transition state.
So, the correct answer is option E.
Question 10
1 / -0

In a reaction, reactants form a transition state, before the formation of products. Which of the following is affected by the action of enzyme?

A
Products only

B
Reactants only

C
Transition state only

D
Products and reactants

E
Transition state and products

Solution

Any chemical reaction includes the formation of transition state between reactant and product. Formation of transition state requires high energy content of reactant molecules for alignment of reacting groups, the formation of transient unstable charges, rearrangements of chemical bonds etc. The energy required for formation of the transition state is termed as activation energy. Enzymes enhance the rate of reaction by lowering down the activation energy of transition state. Thus, the correct answer is option C.