Match List-I with List-II tracking nitrogenous bases structures:
List-I (Base)
List-II (Chemical Structure Diagram)
(A) Adenine
(I) The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.
(B) Cytosine
(II) The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.
(C) Thymine
(III) The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.
(D) Uracil
(IV) The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.
Choose the correct answer from the options given below :
A.\text{(A)-(III), (B)-(IV), (C)-(II), (D)-(I)}
B.\text{(A)-(III), (B)-(I), (C)-(IV), (D)-(II)}
C.\text{(A)-(IV), (B)-(III), (C)-(II), (D)-(I)}
D.\text{(A)-(III), (B)-(IV), (C)-(I), (D)-(II)}
Solution & Explanation
### Core Logic
Let's identify the chemical structures of the nitrogenous bases used in nucleic acids:
* **(A) Adenine:** A purine derivative featuring a characteristic fused bicyclic ring system with an amino substituent at position 6 (6-aminopurine)
ightarrow$
ightarrow$ **(III)**.
* **(B) Cytosine:** A pyrimidine monocyclic derivative with an amino group at position 4 and a carbonyl group at position 2 (4-amino-2-oxo-pyrimidine)
ightarrow$
ightarrow$ **(IV)**.
* **(C) Thymine:** Found in DNA, this pyrimidine derivative features a methyl substituent at position 5 along with carbonyl groups at positions 2 and 4 (5-methyl-2,4-dioxo-pyrimidine)
ightarrow$
ightarrow$ **(II)**.
* **(D) Uracil:** Found in RNA, this pyrimidine derivative lacks the methyl group found in thymine, featuring just carbonyl groups at positions 2 and 4 (2,4-dioxo-pyrimidine)
ightarrow$
ightarrow$ **(I)**.
Matching these structures gives the sequence: (A)-(III), (B)-(IV), (C)-(II), (D)-(I).
### Step-by-Step Structural Validation
The biochemical structures correspond to the following configurations:
The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.The Match List contains nitrogenous bases aligned with their corresponding biochemical molecular ring structures.
### Pattern Recognition
Quick identification keys:
- Bicyclic ring = Adenine
- Monocyclic ring with a -mathrmCH_3$-\mathrm{CH}_3$ group = Thymine
- Monocyclic ring without a -mathrmCH_3$-\mathrm{CH}_3$ group = Uracil
- Monocyclic ring with an amino group (-mathrmNH_2$-\mathrm{NH}_2$) = Cytosine
### Evaluation Rubric / Model Answer
null
### Chapter Mix
Class 12 Chemistry: Biomolecules
### Core Logic
Fehling's reagent is reduced by reducing sugars to give a reddish-brown precipitate of Cu_2O$Cu_2O$.
Reducing sugars must have a free aldehyde/ketone group or a hemiacetal linkage that can open to form an aldehyde.
Sucrose is a non-reducing sugar because its anomeric carbons (C1 of glucose and C2 of fructose) are tied up in a glycosidic linkage, leaving no free hemiacetal group.
### Step 1: Analyzing the options
Lactose, glucose, and maltose are all reducing sugars and will give a positive Fehling's test. Sucrose does not.
### Pattern Recognition
Sucrose = non-reducing sugar. Maltose, Lactose = reducing sugars. Monosaccharides (glucose, fructose) = always reducing.
### Evaluation Rubric / Model Answer
null
### Chapter Mix
Class 12 Chemistry: Biomolecules
Q89jee_main_2024_31_jan_eveningVitamins and their Classification
From the vitamins A, B_1$B_1$, B_6$B_6$, B_12$B_{12}$, C, D, E and K, the number vitamins that can be stored in our body is ________
Numerical Answer.Answer: 5 to 5
Solution
### Core Logic
Vitamins are broadly classified into two groups based on solubility:
1) Fat-soluble vitamins: Vitamins A, D, E, and K. These are stored in the liver and adipose (fat-storing) tissues.
2) Water-soluble vitamins: B group vitamins and Vitamin C. These are readily excreted in urine and cannot be stored in the body (with the exception of Vitamin B_12$B_{12}$, which can be stored in the liver).
### Step 1: Final List
The vitamins that can be stored in the body from the given list are A, D, E, K, and B_12$B_{12}$.
Total number = 5$5$.
### Evaluation Rubric / Model Answer
null
### Chapter Mix
Class 12 Chemistry: Biomolecules
Q78jee_main_2024_31_jan_morningReactions of Glucose
Match List I with List II
LIST-I
LIST-II
A. Glucose/NaHCO_3$NaHCO_3$/Delta$\Delta$
I. Gluconic acid
B. Glucose/HNO_3$HNO_3$
II. No reaction
C. Glucose/HI/Delta$\Delta$
III. n-hexane
D. Glucose/Bromine water
IV. Saccharic acid
Choose the correct answer from the options given below:
### Core Logic
Matching the reactions of glucose:
(A) Glucose does not react with NaHCO_3$NaHCO_3$, so there is no reaction. (A rightarrow$\rightarrow$ II)
(B) Oxidation of glucose with strong oxidizing agents like HNO_3$HNO_3$ yields a dicarboxylic acid called saccharic acid. (B rightarrow$\rightarrow$ IV)
(C) Prolonged heating of glucose with HI$HI$ forms n-hexane, indicating a straight chain of six carbon atoms. (C rightarrow$\rightarrow$ III)
(D) Oxidation with mild agents like bromine water converts glucose to gluconic acid. (D rightarrow$\rightarrow$ I)
### Evaluation Rubric / Model Answer
null
### Chapter Mix
Class 12 Chemistry: Biomolecules
More Biomolecules Questions — jee_main_2025_24_jan_evening
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