Which one of the following characteristics is common both in humans and adult frogs?
- Four chambered heart
- Internal fertilization
- Nucleated RBCs
- Ureotelic mode of excretion
Answer
(4) Ureotelic mode of excretion
Solution
(1) Frog has a three chambered heart (two auricles, one ventricle); humans have a four chambered heart.
(2) Fertilisation in frog is external; in humans it is internal.
(3) RBCs of frog are nucleated; human RBCs are enucleated.
(4) As per NCERT, mammals and many terrestrial amphibians (adult frog) are ureotelic. ⇒ Common feature.
Answer: (4)