Analogous structures are structures which serve similar function in different organisms and evolved independently in two living organisms while homologous structures are the structures which are similar in related orgnanism due to inheritance.
The wings of Pterodactyl, bats and birds are conisdered as analogous structure. <u>they are similar in structure and same in function and evolved independently in the two groups of animals.</u>
Bones in forelimbs of pterodactyl, bats and birds are considered homologous structures as <u>they inherited the pattern from a common ancestor and have different functions.</u>
When calcium concentration increases during depolarization, it shifts the conformation of troponin and tropomyosin, and actin is able to associate with myosin. As calcium is taken up again by the sarcoplasmic reticulum the muscle cell relaxes.
