Questions

The femur is the longest bone in the human body. It is also called as thigh bone. Stapes in the shortest bone in the body that is present in the middle ear.

Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. These plates which float on and travel independently over the mantle and much of the earth's seismic activity occurs at the boundaries of these plates.

The seven major plates are the African plate, Antarctic plate, Eurasian plate, Indo-Australian plate, North American plate, Pacific plate and South American plate.

Volcanoes usually form along plate boundaries , where tectonic plates are either moving towards or away from one another. They may be convergent or divergent.

The boy fell off the bicycle.

An ionic bond is formed between two molecules when transfer of valency electrons take place between them. 

Tetrad is a homologous chromosome pair in the given options. A homologous chromosome pair is a pair of chromosomes one from father and one from mother that has same gene sequence after the process of meiosis.

The first electric train of India was opened in 1925. The first electric train ran between Bombay (Victoria Terminus) and Kurla, a distance of 16 km.