Connecting link between annelids and molluscs is

• Neopilina

• Peripatus

• Periplaneta

• Limulus

Which compound has a very important role in prebiotic evolution?

• Sulphur dioxide

• Nitric oxide

• Methane

• Sulphur trioxide

The velocity of conduction of nerve impulse in frog is

• 300 m/s

• same as of electricity

• faster than sound

• 30 m/s

In parasympathetic nervous system, which of the following is released?

• Epinephrine

• Norepinephrine

• Serotonin

• Acetylcholine

Which of the following is important for muscle contraction and nerve impulse transmission?

• Ca²⁺ ions

• Ca²⁺ and Mg²⁺ ions

• Mg²⁺ ions

• Fe²⁺ ions

Heparin is synthesized in

• liver

• kidney

• saliva

• pancreas

Which one is component of Ornithine cycle?

• Ornithine, citrulline and alanine

• Ornithine, citrulline and arginine

• Amino acids are not used

• Ornithine, citrulline and fumaric acid

Ruminants belong to order

• Proboscida

• Artiodactyla

• Marsupials

• Edentata

Entamoeba histolytica differs from Amoeba in absence of 

• pseudopodia

• contractile vacuole

• nucleus

• ectoplasm

Sea gulls excrete excess of NaCl from

• liver

• lungs

• nasal activity

• kidney