Muscles, which pull the bone towards the body, are called flexor muscles, while those acting in the opposite direction are called extensor muscles.

Cartilages are found between two or more bones. They prevent bones from rubbing against each other. 

Hydra uses its tentacles to move, and it shows both looping and somersault movement. 

Sundew plant shows chemonastic movement as it bends its tentacles on its leaves over certain insects, when they touch the leaves.

The movement of plant parts towards light are said to be positively phototropism. 

The human body is supported by a framework of bones, called skeleton. The skeleton consists of 206 bones. 

Mimosa, i.e. the 'touch me not' plant shows nastic movement in response to touch.

Immune system protects the body against infection. Skeletal system has no role in protecting body against infection. 

Pivot joints are present in neck, hinge joint is present in knee and elbow, and Ball and socket joints are present in hip and shoulder.

By definition, tissue is a group of cells, which have a similar structure and perform a common specific function. The tissues are present in both plants and hence, (3) is incorrect.

Insects like ants and spiders move with the help of their jointed legs. 

Pivot joints make twisting movement possible. It is a pivot joint that lets your neck from side to side. 

Multicellular organisms develop a complex body structure and the cells are not exposed for long time to the air or water media for exchange of materials. Hence, specialized tissues become necessary to reach all the cells and do the needful activities like gaseous exchange, supply of food, removal of excretory products from all the cells. For this, cells do not increase in size; they are only more in number. Movements increase as a result of efficient working of tissues. Further, there are many multicellular organisms, which are small or minute in size. Hence, tissues are basis of structure and not size. 

Hinge joint allows movement only in one direction. For example the knee and elbow can bend and straighten, but cannot rotate.

Movement of plant in response to light is called phototropism, in response to gravity is called geotropism, in response to water is called hydrotropism and in response to touch is called thigmotropism.