At iso-electric point:

(a) conc. of cation is equal to conc of anion

(b) Net charge is zero.

(c) Maximum conc. of di-polar ion (Zwitterion) will be present

(d) All of the above

Which amino acid does not contain chiral centre ?
(1) Valine
(2) Leucine
(3) Glycine
(4) Iso-leucine

Which of the following pair gives same phenyl osazone ?

(a) D-Glucose and D-Allose
(b) D-Glucose and D-Alfrose
(c) D-Glucose and D-Mannose
(d) D-Glucose and D-Talose

Proteins mainly contain:

(1) C, H, O and N

(2) Only C and H

(3) C, H and O

(4) N and H

The main structural feature of protein is:

(1) The ester linkage

(2) The ether linkage

(3) The peptide linkage

(4) All of these

Keratin, a structural protein is present in:
(a) hair
(b) skin
(c) wool
(d) all of these

Blood protein is ?
(a)albumin
(b)haemoglobin
(c)both (a) and (b)
(d)none of these

A vitamin which plays a vital role in the coagulating property of blood is:-

(1) Vitamin A
(2) Vitamin D
(3) Vitamin B
(4) Vitamin K

Which is not a poison for enzymes?

(a) CN^-                       (b) Fe³⁺

(c) Pb²⁺                     (d) ${\mathrm{AsO}}_4^{3-}$

The non-proteinous substances which certain enzymes require for their activity are called:

(a) catalysts                      (b) inhibitors

(c) co-enzymes                  (d) epimers