NCERT solutions for class 11 biology chapter 20 locomotion movement is one of the important study material for the students of class 11. The topics which are taught in class 11 are the basics of the topics which will be taught in class 12. To score good marks in class 11th examination one must solve the NCERT questions questions which are provided at the end of each chapter.
The class 11 NCERT solutions for biology chapter 20 are provided here so that students can refer to these solutions for better clarification and understanding.
This chapter specifically deals with how you move about using your limbs and the related muscles and bones. Movement is something that differentiates plants from the animals. Multicellular animals developed movement as a way of getting from point A to point B either to feed or to evade predators. It is also important to adapt to the environment or move to a more favorable environment. Also, evolution played an important role in locomotion. Us humans are tetrapod, meaning we got 2 pairs of limbs. This lineage includes almost all vertebrates. Even snakes are considered tetrapods because they evolved from ancestors who had 2 pairs of limbs.
(a) Actin and Myosin
(b) Red and white muscles
(c) Pectoral and Pelvic girdle
Q6: Match Column I with Column II :
Locomotion and movement is an important function in animals. They help the organisms to find food or acquire prey, evade predators, and find mates. Also, it helps the organisms to migrate and adapt to new and favorable environments. Anatomically speaking, most vertebrates are tetrapods, meaning that they have two pairs of limbs. Humans, cows, horses all are tetrapods as they obviously have 4 limbs. Even animals that seem like they don’t have any limbs like snakes are considered tetrapods because they have ancestors who had four limbs. This theory was also proved when scientists discovered a fossil of a snake that had 4 small limbs protruding from its body. But scientists have theorized that the limbs were not meant for walking – it was probably used during mating or to hold on to unruly prey.
Humans have several muscles in their limbs, in tandem with bones that provide strength and structure to aid locomotion. There are many muscle types that are adapted to fulfill this function by having specialized cells and tissues suited for the task. Besides this, single cells also move – For instance, did you know that human White Blood Cells can sprout many legs like a millipede and crawl along the walls of the blood vessels towards the site of an injury?