1. Mammals have _______ glands which secrete milk.   pituitary   adrenal   mammary   Hint Half-n-half Clue   2. The larvae of house-flies are known as _______.   maggots   pupas   caterpillars   Half-n-half Clue   3. Slow-worms and grass-snakes can be classified as reptiles which is one of the classes of vertebrates.   False   True   4. Pick the "odd one out" (with reference to crustaceans and molluscs).   Crab   Shrimp   Mussel   Half-n-half Clue   5. Frogs have _______ as their hearing organs.   sensitive feelers   lateral lines   external eardrums   Half-n-half Clue   6. The part of the alimentary canal that absorbs water is the _______.   colon   rectum   caecum   Half-n-half Clue   7. Each of the hind feet of a frog has 4 toes.   True   False