State True or False. The internal structure and arrangement of bones of the forelimbs of frog, lizard, bird, bat and man are different.

State True or False. The wings of birds and those of insects are homologous organs.

State True (T) or False (F). Potassium is the constituent of ring structure of chlorophyll.

State True or False.Nerve cells have special proteins that change their shape and arrangement for conduction of impulse.

Study following statements (P to R) and choose the correct alternative : P: Those organs which have the same internal structure but different functions are called homologous organs. Q: Organs which have different basic design but have similar appearance and carry out similar functions are called analogous organs. R: The impressions of dead plants or animals that lived in the past are known as fossils. a.Only R is true. b.All the three statements are true. c.Statements P and Q are true, but R is false. d.All the three statements are false.

State True or False. Two different species originated from a common ancestor can mutually reproduce amongst themselves.

State if each of the following statements is true or false. Give reasons for your answer. Total energy of a system is always conserved, no matter what internal and external forces on the body are present.

State whether each of the following statements is true or false : If the areas of two sectors of two different circles are equal, the lengths of their corresponding arcs are equal.

State whether each of the following statements is true or false : For an AP, the common difference can never be zero.

State whether each of the following statements is true or false : For an AP for which the common difference is negative, it is possible that the sum of its first m terms and first n terms are equal.