It is said that elemental composition of living organisms and that of inanimate objects (like earth’s crust) are similar in the sense that all the major elements are present in both. Then what would be the difference between these two groups? Choose a correct answer from among the following:
- a.Living organisms have more gold in them than inanimate objects.
- b.Living organisms have more water in their body than inanimate objects.
- c.Living organisms have more carbon, oxygen and hydrogen per unit mass than inanimate objects.
- d.Living organisms have more calcium in them than inanimate objects.
Many elements are found in living organisms either free or in the form of compounds. Which of the following is not found in living organisms?
- a.Silicon
- b.Magnesium
- c.Iron
- d.Sodium
Aminoacids, have both an amino group and a carboxyl group in their structure. Which one of the following is an amino acid?
- a.Formic acid
- b.Glycerol
- c.Glycolic Acid
- d.Glycine
An aminoacid under certain conditions have both positive and negative charges simultaneously in the same molecule. Such a form of aminoacid is called
- a.Acidic form
- b.Basic form
- c.Aromatic form
- d.Zwitterionic form
Sugars are technically called carbohydrates, referring to the fact that their formulae are only multiple of C(H2O). Hexoses therefore have six carbons, twelve hydrogens and six oxygen atoms. Glucose is a hexose. Choose from among the following another hexose.
- a.Fructose
- b.Erythrose
- c.Ribulose
- d.Ribose
When you take cells or tissue pieces and grind them with an acid in a mortar and pestle, all the small biomolecules dissolve in the acid. Proteins, polysaccharides and nucleic acids are insoluble in mineral acid and get precipitated. The acid soluble compounds include aminoacids, nucleosides, small sugars etc. When one adds a phosphate group to a nucleoside, one gets another acid soluble biomolecule called
- a.Nitrogen base
- b.Adenine
- c.Sugar phosphate
- d.Nucleotide
When we homogenise any tissue in an acid the acid soluble pool represents
- a.Cytoplasm
- b.Cell membrane
- c.Nucleus
- d.Mitochondria
The most abundant component of living organisms is
- a.Protein
- b.Water
- c.Sugar
- d.Nucleic acid
A homopolymer has only one type of building block called monomer repeated ‘n’ number of times. A heteropolymer has more than one type of monomer. Proteins are heteropolymers usually made of BIOMOLECULES 45
- a.20 types of monomers
- b.40 types of monomers
- c.30 types of monomers
- d.only one type of monomer
Proteins perform many physiological functions. For example, some functions as enzymes. Which of the following represents an additional function that some proteins discharge?
- a.Antibiotics
- b.Pigment conferring colour to skin
- c.Pigments making colours of flowers
- d.Hormones
Glycogen is a homopolymer made of
- a.Glucose units
- b.Galactose units
- c.Ribose units
- d.Aminoacids
The number of ‘ends’ in a glycogen molecule would be
- a.Equal to the number of branches plus one
- b.Equal to the number of branch points
- c.One
- d.Two, one on the left side and another on the right side
The primary structure of a protein molecule has
- a.Two ends
- b.One end
- c.Three ends
- d.No ends
Enzymes are biocatalysts. They catalyse biochemical reactions. In general they reduce activation energy of reactions. Many physico-chemical processes are enzyme mediated. Which of the following reactions is not engyme-mediated in biological system?
- a.Dissolving CO2 in water
- b.Untwining the two strands of DNA
- c.Hydrolysis of sucrose
- d.Formation of peptide bond