A novel species with double-stranded genetic material consists of 5 bases namely P , Q , R , S , T , with percentage given below. P Q R S T Percentage 22 28 22 12 16 Based on the above information, which one of the following inferences is not supported by the observations?

S base pairs with T and Q base pairs with R

S base pairs with Q and T base pairs with Q

P base pairs with R and S base pairs with Q

P base pairs with R and T base pairs with Q

Watson and Crick model of DNA is

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Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

DNA molecule which has the highest number of hydrogen bonds

HARD

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

Assertion $(A) :$ Between $DNA$ and $RNA$ , $DNA$ is a better genetic material.

Reason $(R) :$ $2^{'}$ $- OH$ group present in every nucleotide in $RNA$ is a reactive group and make $RNA$ labile and easily degradable.

The correct answer is:

HARD

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

DNA molecule has length of $476 \overset{\circ}{A}$ with $20 %$ guanosine. Choose the correct features of $DNA$

$I)$ $56 CTP$
$II)$ $336$ Hydrogen bonds
$III)$ Total $150$ nucleotides
$IV)$ $84 TTP$

HARD

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

A newly discovered organism possesses a genetic material with a new base composition consisting of the sugar and phosphate backbone as found in existing natural

DNA

. The five novel bases in this genetic material-namely,

P, Q, R, S, T

are heterocyclic structures with

1, 1, 2, 2

and

3

rings, respectively. Assuming the new

DNA

forms a double helix of uniform width, which one of the following would be the most appropriate base pairing?

EASY

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

Considering the average molecular mass of a base to be 500 Da, what is the molecular mass of double stranded DNA of 10 base pairs?

HARD

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

A novel species with double-stranded genetic material consists of

5

bases namely

P, Q, R, S, T,

with percentage given below.

	$P$	$Q$	$R$	$S$	$T$
Percentage	$22$	$28$	$22$	$12$	$16$

Based on the above information, which one of the following inferences is not supported by the observations?

MEDIUM

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

Choose the correct statement

I)

Secondary metabolites do not have identifiable physiological processes in plants, fungal and microbial cells

I I)

Bio macromolecules are acid insoluble organic compounds with mol wt more than

10, 000

daltons

I I I)

Uridylic acid and cytidylic acids are derived from uracil and cytosine by esterification

I V)

Lecithin and lectin are phospholipids found in cell membrane

MEDIUM

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

What is the difference between a nucleoside and a nucleotide?

EASY

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

If a double-stranded

DNA

has

15 %

cytosine, what is the

%

of adenine in the

DNA

?

MEDIUM

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

The sequences of four DNA molecules are given. Which one of these DNA molecules will have the highest melting temperature

(T_{m})

?

MEDIUM

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

Match the following lists:

	List $I$		List $II$
A)	X-ray diffraction data	$I)$	Chargaff
B)	DNA double stranded	$II)$	Meischer
C)	DNA double helix	$III)$	Wilkins
D)	DNA as an acidic substance	$IV)$	Watson $&$ Crick

The correct match is

EASY

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

If a dsDNA has 20% adenine, what would be its cytosine content?

HARD

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

A bacteriophage

T 2

particle contains within its head a double-stranded

B

-from DNA of molecular weight

1.2 \times 10^{8} Da .

Assume that the head of a

T 2

Phage particle is of

210 nm

in length and the average molecular weight of a nucleotide is

330 Da .

The length of the

T 2

genome is in the range of

HARD

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

The average energy of each hydrogen bond in

A - T

pair is

x kcal

{mol}^{- 1}

and that in

G - C

pair is

y {kcalmol}^{- 1}

. Assuming that no other interaction exists between the nucleotides, the approximate energy required in

{kcalmol}^{- 1}

to split the following double stranded

DNA

into two single strands is
Question Image

[Each dashed line may represent more than one hydrogen bond between the base pairs]

EASY

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

In a segment of DNA with

10

base pairs, the number of sugar molecules are __________.

EASY

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

Assertion (

A

): Purine always comes opposite to a pyrimidine.
Reason (R): Appropriate uniform distance is maintained between the two strands of the

DNA

helix.

EASY

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

If Adenine makes

30 %

of the DNA molecule, what will be the percentage of Thymine, Guanine and Cytosine in it?

EASY

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

Which one of the following is the complementary sequence for the DNA with

5^{'} - C G T A C T A - 3^{'}

MEDIUM

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

What is the length of human DNA containing

6.6 \times 10^{9} b p

?

MEDIUM

Life Sciences>From Molecules to Organisms: Structures and Processes>Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.>Structure and Function - Systems of specialized cells within organisms help them perform the essential functions of life.All cells contain genetic information in the form of DNA molecules. Genes are regions in the DNA that contain the instructions that code for the formation of proteins, which carry out most of the work of cells.

In sea urchin DNA, which is double-stranded,

17 %

of the bases were shown to be cytosine. What are the percentages of other three bases expected to be present in this DNA?

Watson and Crick model of DNA is

Important Questions on Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.

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