CBSE Questions for Class 12 Engineering Chemistry Biomolecules Quiz 15 - MCQExams.com

The production of starch, and not glucose, is often used as a measure of photosynthesis in leaves because 
  • starch is immediete product of photosynthesis.
  • Glucose formed in photosynthesis soon gets converted into starch
  • Starch is soluble in water.
  • Sugar can not be tested.
State whether the following statements are True or False:
Raffinose is a trisaccharide. On hydrolysis, it gives three molecules of glucose.
  • True
  • False
State whether the following statements are True or False:
Vitamin C is synthesised in skin cells in sunlight. 
  • True
  • False
Ampholyte is :
  • $$H_2O$$
  • $$Zn(OH)_2$$
  • $$H_2NCH_2COOH$$
  • all of these
In the table given above the acidic amino acids are______
  • I, II
  • I, III
  • II, III
  • I, II & IV
The metal present in $$Vitamin \ B_{12} $$ is
  • Magnesium
  • Iron
  • Cobalt
  • Manganese
An organic compound answers Molisch's test as well as Benedict's test.But it does not answer Scliwanoffs test.Most probably, it is 
  • Sucrose
  • Protein
  • Fructose
  • Maltose
A carbohydrate that cannot be hydrolysed to simpler forms is called :
  • Disaccharide
  • Monosaccharide
  • Polysaccharide
  • Trisaccharide
Starch can be used as an indicator for the detection of traces of
  • Glucose in aqueous solution
  • Proteins in blood
  • Iodine in aqueous solution
  • Urea in blood
Nitrous acid $$(HNO_2)$$ converts amino acids into hydroxy acids with retention of configuration. Estimation of nitrogen gas evolved in the reaction is the reaction is the basis of Van slyke estimation of amino acids.

$$R - \overset{NH_2}{\overset{|}{C}H} - COOH \xrightarrow{HNO_2} R - \overset{OH}{\overset{|}{C}H} - COOH + N_2 \uparrow + H_2O$$

Which of the following amino acids cannot be analysed by Van slyke method? 

1751514_23fd8f475c304d30845b9ba05d63813c.JPG
  • Only I
  • Only II
  • I and III
  • I, III, IV
Sugars are 
  • Optically active polyhydroxy aldehydes
  • Optically active polyhydroxy ketones
  • Optically active polyhydroxy aldehydes or ketones
  • Polyhydroxy aldehydes or ketones which may or may not be optically active
The standard compound for determination of configuration in the 'sugar chemistry' is 
  • Glycolaldehyde
  • Glyceraldehyde
  • Glucose
  • Fructose
Glucose and fructose form
  • Same osazone
  • Same acid on oxidation
  • Same alcohol when reduced
  • Different osazone
Carbohydrates are
  • Hydrates of carbon
  • Polyhydroxy aldehydes or ketones
  • Polyhydroxy acid compounds
  • None of these
Which of the following shows the maximum hydrophobic behaviour
  • Glycerine
  • Stearic acid
  • Glucose
  • Adenine
Which of the following is not present in nucleic acids
  • Uracil
  • 2-aminopyridine
  • Thymine
  • Adenine
Ascorbic acid is a
  • Vitamin
  • Enzyme
  • Protein
  • Carbohydrate
Which $$\alpha$$ amino acid can cross link peptide chains
  • Serine
  • Cysteine
  • Protein
  • Carbohydrate
Which carbohydrates has highest abundance in human blood
  • d-fructose
  • d-glucose
  • Sucrose
  • Lactose
The optically inactive amino acid is
  • Lysine
  • Glycine
  • Arginine
  • Alanine
Galactose is converted into glucose in
  • Mouth
  • Stomach
  • Liver
  • Intestine
Which substance is not present in nucleic acid
  • Cytosine
  • Adenine
  • Thymine
  • Guanidine
Vitamin A is present in
  • Cod liver oil
  • Carrot
  • Milk
  • In all of these
In RNA , nitrogen bases are 
  • Adenine and guanine and cytosine and thymine
  • Adenine and guanine and thymine and cytosine
  • Adenine and thymine and guanine and cytosine
  • Adenine and guanine and uracil and cytosine
Lysine, is ________
1797040_b798a5843b084c0b9030484f7a85ac0c.png
  • $$\alpha$$- Amino acid
  • Basic amino acid
  • Amino acid synthesised in body
  • $$\beta$$- Amino acid
Which of the following is the correct statement?
  • Starch is a polymer of $$\alpha-$$glucose.
  • Amylose is not a component of starch.
  • Proteins are composed of only one type of amino acid.
  • In the cyclic structure of fructose, there are five carbon atoms and one oxygen atom.
Which of the following vitamins is water soluble
  • Vitamin $$E$$
  • Vitamin $$D$$
  • Riboflavin
  • Retinol
Nucleic acid are

  • Small molecules
  • dipepetides
  • Long chain polymers of nuceotides
  • Polypeptides
Nuclei acids are polymers of ________.
  • nucleosides
  • nucleotides
  • bases
  • sugars.
In what respect enzymes are different from catalysts?
  • High diffusion rate
  • Active at high temperature
  • Protein nature
  • Used in the reaction
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 12 Engineering Chemistry Quiz Questions and Answers