BIOLOGY IS THE STUDY OF EXCEPTIONS

1)The  heart of reptiles are 3 chambered except in crocodile and aligator where it is 4 chambered.
2)Lungs are absent in fishes but lung fishes have lungs as well as gills .
3) mammals give birth to their babies but Duck  billed platypus and spiny ant eater are egg laying mammals .
4)RBCs are circular and biconcave  in mammals except camel and LIama where they are oval and flat.
5) Larva  of american salamander can reproduce sexually and the phenomenon is called pedogenisis.
6) the drones of honey bee are developed from unfertilised eggs.
7)ostrich and kiwi are the birds that cannot fly.
8)DNA is double stranded but in virus coliphase *174 it is single stranded and also RNA is commonly single stranded but in Rheo virus it is double stranded .
8)roots of the plants are normally positive geotropism the roots of mangroove are negative geotropismand known as pneumatophores.
9)roots are non green and non photosynthetic but they are green and photosynthetic in Tinospora.
1o)stem are normally aerial but in no of plants they have underground eg banana, colocassia,ginger.
11)yucca and Dracaena although being  monocot show secondary growth.