functions of proteins

Q. Give distinguishing features of each type of structure?

Ans:     In primary structure, there is a linear sequence of amino

acids. Secondary structure contains protein resulting from hydrogen bond interaction b/w amino acids which are very close to each other. Tertiary structure refers to polypeptide chains forming complex after coiling and folding. Quaternary structure defines the structure resulting from interactions between separate polypeptides units having more than one subunits.

What are major classes of proteins on the basis of functions?

(I)        Structural proteins (Collagen)

(ii) Storage proteins (Ferritin)

(iii) Contractile proteins (Myosin)

(iv)             Enzymes

(v)               Protective proteins (Fibrinogen)

(vi)             Transport proteins (Haemoglobin)

(vii)           Growth hormones

(viii)         Toxins.

Q. What are derived proteins?

Ans:     These are degradation products of simple & conjugated

proteins e.g., peptides, peptones etc.

Q. Write down at least two examples of oxygen­transporting proteins.

Ans:     (i) Myoglobin               (ii) Haemoglobin

Q. What are blood proteins?

Ans:     These are present in blood plasma. These include serum,

albumin, glyco proteins etc.