531. Fish that have hand and legs: 
Answer: Latimer

532. Tusk of the elephant is a modification of: 
Answer: Incisors

533. Ichthyology is the study of: 
Answer: Fish

534. Emu is a native of: 
Answer: Australia

535. The bird that lives in Rookery: 
Answer: Penguin

536. Archiopterics are the ancestors of: 
Answer: Birds

537. The bone above the elbow: 
Answer: Humerus

538. The bones below the elbow: 
Answer: Radius and Ulna

539. The bones below the knee: 
Answer: Tibia and Fibula

540. The bone above the knee: 
Answer: Femur

541. What is known as the ‘relay station of the brain’? 
Answer: Thalamus

542. Jarvic-7 is the name of artificial…… 
Answer: Heart

543. The wavy motion of food through the alimentary canal is: 
Answer: Peristalsis

544. Which gland is known as ‘biological clock’? 
Answer: Pineal gland

545. The hormone that regulates water in the human body: 
Answer: Vasopressin

546. What per cent of the total energy in the human body is utilized by the brain?
Answer: 20

547. The enzyme in the intestine that digests protein: 
Answer: Pepsin

548. The plant food which is the richest source of protein: 
Answer: Soyabean

549. What is known as the ‘blood bank in the human body’? 
Answer: Spleen

550. The substance that causes tears while handling onion: 
Answer: Phosphorus

551. Which gland is known as Adam’s apple?
Answer: Thyroid