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three different amino acids joined in different sequence to form different types of tri-peptide
Three different amino acids can form different types of tri-peptides. The number of possible sequences is given by the permutations of 3 different amino acids taken 3 at a time, which is 3! (3 factorial), equal to 6.
Which of the following sentence is true or false? (symbol for true is T, and for false it’s F) (i) group attached to Cl in cyclic structure of glucose acts as reducing agent group, this glucose is one monosaccharide unit of sucrose (ii) group attached to Cl in cyclic structure of glucose acts as reducing agent group, this glucose is one monosaccharide unit of maltose (iii) in maltose two monosaccharide units are joined to each other (iv) group attached to C4 in cyclic structure of galactose acts as reducing agent group
Explanation: (i) False - The group attached to Cl (carbon 1) in the cyclic structure of glucose acts as a reducing agent, but this glucose is not a part of sucrose. In sucrose, glucose is non-reducing. (ii) True - The group attached to Cl (carbon 1) in the cyclic structure of glucose acts as a reducing agent, and this glucose is one monosaccharide unit of maltose. (iii) True - In maltose, two monosaccharide units are joined to each other via a glycosidic bond. (iv) False - The group attached to C4 in the cyclic structure of galactose does not act as a reducing agent. The reducing group is at carbon 1.
cellulose consist of long chain of
Explanation: Cellulose is a polysaccharide consisting of a linear chain of several hundred to many thousands of β-D-glucose units. The β(1→4) linkages in cellulose result in a straight, unbranched chain that forms strong fibrous structures.
Amino acid is given in Column-1 & its nature is given in Column-ll so match the following Column 1 i. lysine ii. glysine iii. arginine iv. Alanine Column II a. acidic b. basic c. nutral
Explanation: (i) Lysine is basic due to the presence of an extra amino group in its side chain. (ii) Glycine is neutral as it has no additional functional groups in its side chain. (iii) Arginine is basic due to the presence of a guanidino group in its side chain. (iv) Alanine is neutral as it has a simple alkyl side chain.
chemical reactions are given in section I and chain or group present in structure of glucose are given in section II. Match Section-I with Section-II Section-I i. glucose forms oxime with hydroxyl amine ii. glucose is oxidized by nitric acid and give saccharic acid iii. glucose is oxidized by bromine water and givegluconicacid iv. glucose forms penta-acitile glucose with aceticenhydride in presence of pyridine Section-II a. OHC-C-C-C-C-C chain is present b. carbonyl group is present c. OHC-C(OH)-C(OH)-C(OH)-C(OH)-CH2OH chain is present d. OHC-C-C-C-C-CH2OH chain is present
Let's break down the reactions and match them with the corresponding groups:
Glucose forms oxime with hydroxylamine: This reaction indicates the presence of a carbonyl group (aldehyde or ketone). Hence, this matches with 'b'.
Glucose is oxidized by nitric acid to give saccharic acid: This reaction indicates the presence of an aldehyde group at the end of the carbon chain, which gets oxidized to a carboxylic acid. Hence, this matches with 'd': OHC-C-C-C-C-CH2OH.
Glucose is oxidized by bromine water to give gluconic acid: This oxidation specifically targets the aldehyde group, forming a carboxylic acid while the rest of the carbon chain remains the same. Hence, this matches with 'a': OHC-C-C-C-C-C.
Glucose forms penta-acetate with acetic anhydride in the presence of pyridine: This indicates the presence of hydroxyl groups which are acetylated. Hence, this matches with 'c': OHC-C(OH)-C(OH)-C(OH)-C(OH)-CH2OH.
So, the correct matching is i-b, ii-d, iii-a, iv-c.
Which of the following sentence is true or false ? (symbol for true isT, and for false it's F) i. in maltose anomeric carbon of two monosaccharide units are involved in formation of glycosidic bond ii. in sucrose anomeric carbon of one monosaccharide unit is involved in formation of glycosidic bond iii. in lactose anomeric carbon of one monosaccharide unit is involved in formation of glycosidic bond
structure of protein given in column I, Shape & example of protein is given in Column II & its bond is given in Column III, so match following, COLUMN I i. primary structure ii. secondary structure iii. tertiary structure iv. quaternary structure COLUMN II a. $ \beta $ - platinated b. myoglobin c. insulin d. hemoglobin COLUMN III P. hydrogen bond Q.disulphide bond R. ionicbond S. vanderwall’s force
Let's match each structure with its shape, example, and bond types:
Primary structure: This refers to the linear sequence of amino acids in a protein. Insulin is a classic example of a protein with a defined primary structure, and disulfide bonds can be present. Hence, i-c-Q.
Secondary structure: This refers to local folded structures that form within a polypeptide due to interactions between atoms of the backbone. The β-pleated sheet is one such structure, and hydrogen bonds are crucial for its stability. Hence, ii-a-P.
Tertiary structure: This refers to the overall three-dimensional structure of a single protein molecule. Myoglobin is an example of a protein with a well-defined tertiary structure, and it can have multiple bond types including hydrogen bonds, disulfide bonds, ionic bonds, and van der Waals forces. Hence, iii-b-P,QR,S.
Quaternary structure: This refers to the structure formed by several protein molecules (polypeptide chains), usually called protein subunits. Hemoglobin is an example, and it involves multiple types of bonds including hydrogen bonds, ionic bonds, and van der Waals forces. Hence, iv-d-P,QR.
So, the correct matching is i-c-Q, ii-a-P, iii-b-P,QR,S, iv-d-P,QR.
Which of the following sentence is true or false ? (symbol for true is T and for false is F)
i. message forthe synthesis of a specific protein is present in DNA
ii. cytosine base is derivatives of pyrimidine
iii. $ \beta $ -D ribose sugar present in DNA iv. DNA is the exclusively responsible for maintaining the identity of different species of organism upto 100 years
what are alpha - D+glucose & beta - D + glucose?
Alpha-D-glucose and beta-D-glucose are anomers. Anomers are a type of stereoisomer and specifically differ at the anomeric carbon. For glucose, this is the carbon-1 (C1) position. In alpha-D-glucose, the OH group attached to C1 is on the opposite side (trans) of the CH2OH group, whereas in beta-D-glucose, the OH group on C1 is on the same side (cis) as the CH2OH group.
which statement is appropriate for anomer of glucose ?
Anomers are isomers of glucose that differ in structure specifically at the anomeric carbon (C1) position. This means that their structure changes around the C1 carbon atom, which is the carbon that was part of the carbonyl group in the open-chain form of the sugar. Therefore, the correct statement is 'they are isomers of glucose which contain different structure with $C_1$,' which corresponds to option 2.
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