CLASS X BIOLOGY

CHAPTER 7 – CONTROL & COORDINATION KEY CONCEPTS & GIST OF THE LESSON ˜  Coordination-The working together of various organs of the body of an organism in a proper       manner to produce appropriate reaction to a stimulus is called coordination.    Example : Withdrawal of hand on touching a hot object. Control and Coordination in Animals It is brought about in all animals with the help of two main systems ( a ) Nervous System ( b ) Endocrine System Nervous System Parts of the Nervous system – (i) Brain (ii) Spinal cord (iii) Nerves (Neurons) Functions ( i ) To receive the information from environment ( ii ) To receive the information from various body parts.      (Stimuli ® Response) ( iii ) To act accordingly through muscles and glands. Stimulus : Any change in environment to which the organisms respond and react is called stimulus. E.g., touching a hot plate. Response : The reaction of our body to a stimulus. E.g. withdrawal of our hand o

  Transportation Transportation in human beings - Components of Circulatory system: a)Heart            b) Blood vessels       c) Blood §    Heart -    (Refer to figure 6.10 page no. 106 of N.C.E.R.T  Text book)       (i) It is a muscular organ, which works as a pump in the circulatory system.                        (ii)  It is the size of our fist.                        (iii)  It has two sides, which are separated by a partition so that the oxygenated and                               deoxygenated blood do not get mixed up.                        (iv)  It has four chambers-         Two upper chambers called Atria.          Two lower chambers called Ventricles.     Atria                                                                   Ventricle                                a) Small in size (volume)                                       a) Large in size                                b) Have thin walls.                                                b)