ORGANIC CHEMISTRY-SOME BASIC PRINCIPLES AND TECHNIQUES |Class 11 Chemistry |5PM By Shagun Ma'am |L9

Organic Chemistry L5

12 PM Special Class | Class 11 - STRUCTURE OF ATOM || BOHR MODEL By Yakshu Ma'am

Organic Chemistry- Some Basic Principle & Technique|Catenation|What Is Organic Chemistry?|Importance & Application Organic Chemistry?|Tetra Valence Of C: Shape Of Organic Compound|Question|Structural Representation Of Organic Compound|Complete Structural Formula|Condensed Structural Formula|Bond Line Structural Formula|3D Structure Representation Of Organic Compound|OMR

Read the following information carefully to answer the questions that follow. In a survey of 25 students, it was found that 15 have taken Mathematics. 12 have taken Physics and 11 taken Chemistry, 5 have taken Mathematics and Chemistry, 9 have taken Mathematics and Physics, 4 have taken Physics and Chemistry and 3 have taken all the three subjects. The number of students who have taken only two subjects, is (a)7 (b)8 (c)9 (d)10

Read the following information carefully to answer the questions that follow. In a survey of 25 students, it was found that 15 have taken Mathematics. 12 have taken Physics and 11 taken Chemistry, 5 have taken Mathematics and Chemistry, 9 have taken Mathematics and Physics, 4 have taken Physics and Chemistry and 3 have taken all the three subjects. The number of students who have taken only Physics, is (a)2 (b)3 (c)5 (d)6

In a survey of 25 students, it was found that 15 had taken Mathematics, 12 had taken Physics and 11 had taken Chemistry, 5 had taken Mathematics and Chemistry, 9 had taken Mathematics and Physics, 4 had taken Physics and Chemistry and 3 had taken all the three subjects. The number of students who had taken only physics is :

Read the following information carefully to answer the questions that follow. In a survey of 25 students, it was found that 15 have taken Mathematics. 12 have taken Physics and 11 taken Chemistry, 5 have taken Mathematics and Chemistry, 9 have taken Mathematics and Physics, 4 have taken Physics and Chemistry and 3 have taken all the three subjects. Consider the following statements I. The number of students who have taken only one subject is equal to the number of students who have taken only two subjects. II. The number of students who have taken at least two subjects is four times the number of students who have taken all the three subjects. Which of the above statement(s) is/are correct?

In a survey of 25 students, it was found that 12 have taken physics, 11 have taken chemistry and 15 have taken mathematics; 4 have taken physics and chemistry; 9 have taken physics and mathematics; 5 have taken chemistry and mathematics while 3 have taken all the three subjects Find the number of students who have taken (i) physics only (ii) chemistry only; (iui) mathematics only (iv) physics and chemistry but not mathematics; (v) physics and mathematics but not chemistry; (vi) only one of the subjects; (vii) at least one of the three subjects; (vii) none of the three subjects.

Read the passage given below and answer the question: EVIDENCE FOR THE FIBROUS NATURE OF DNA The basic chemical formula of DNA is now well established. As shown in Figure 1 it consists of a very long chain, the backbone of which is made up of alternate sugar and phosphate groups, joined together in regular 3' 5' phosphate di-ester linkages. To each sugar is attached a nitrogenous base, only four different kinds of which are commonly found in DNA. Two of these---adenine and guanine--- are purines, and the other two thymine and cytosine-are pyrimidines. A fifth base, 5-methyl cytosine, occurs in smaller amounts in certain organisms, and a sixth, 5-hydroxy-methyl-cytosine, is found instead of cytosine in the T even phages. It should be noted that the chain is unbranched, a consequence of the regular internucleotide linkage. On the other hand the sequence of the different nucleotides is, as far as can be ascertained, completely irregular. Thus, DNA has some features which are regular, and some which are irregular. A similar conception of the DNA molecule as a long thin fiber is obtained from physicochemical analysis involving sedimentation, diffusion, light scattering, and viscosity measurements. These techniques indicate that DNA is a very asymmetrical structure approximately 20 A wide and many thousands of angstroms long. Estimates of its molecular weight currently center between 5 xx 10^6 and 10^7 (approximately 3 xx10^4 nucleotides). Surprisingly each of these measurements tend to suggest that the DNA is relatively rigid, a puzzling finding in view of the large number of single bonds (5 per nucleotide) in the phosphate-sugar back bone. Recently these indirect inferences have been confirmed by electron microscopy. (source: Watson, J. D., & Crick, F.H. (1953, January). The structure of DNA. In Cold Spring Harbor symposia on quantitative biology (Vol. 18, pp. 123-131). Cold Spring Harbor Laboratory Press.) Out of the four different kinds of nitrogenous bases which are commonly found in DNA, _______ has been replaced in some organisms.

Read the passage given below and answer the question: EVIDENCE FOR THE FIBROUS NATURE OF DNA The basic chemical formula of DNA is now well established. As shown in Figure 1 it consists of a very long chain, the backbone of which is made up of alternate sugar and phosphate groups, joined together in regular 3' 5' phosphate di-ester linkages. To each sugar is attached a nitrogenous base, only four different kinds of which are commonly found in DNA. Two of these---adenine and guanine--- are purines, and the other two thymine and cytosine-are pyrimidines. A fifth base, 5-methyl cytosine, occurs in smaller amounts in certain organisms, and a sixth, 5-hydroxy-methyl-cytosine, is found instead of cytosine in the T even phages. It should be noted that the chain is unbranched, a consequence of the regular internucleotide linkage. On the other hand the sequence of the different nucleotides is, as far as can be ascertained, completely irregular. Thus, DNA has some features which are regular, and some which are irregular. A similar conception of the DNA molecule as a long thin fiber is obtained from physicochemical analysis involving sedimentation, diffusion, light scattering, and viscosity measurements. These techniques indicate that DNA is a very asymmetrical structure approximately 20 A wide and many thousands of angstroms long. Estimates of its molecular weight currently center between 5 xx 10^6 and 10^7 (approximately 3 xx10^4 nucleotides). Surprisingly each of these measurements tend to suggest that the DNA is relatively rigid, a puzzling finding in view of the large number of single bonds (5 per nucleotide) in the phosphate-sugar back bone. Recently these indirect inferences have been confirmed by electron microscopy. (source: Watson, J. D., & Crick, F.H. (1953, January). The structure of DNA. In Cold Spring Harbor symposia on quantitative biology (Vol. 18, pp. 123-131). Cold Spring Harbor Laboratory Press.) Purines present in DNA are: