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

v   Excretion- The biological process of removal of harmful metabolic wastes in living organisms. Excretion in human beings - (Refer to figure 6.13 page no. 110 of N.C.E.R.T  Text book) §   Organs of excretory system - (i) Kidneys        (iii) Urinary bladder                                                            (ii) Ureters         (iv) Urethra §   Kidneys- (i)                   Two in number (ii)                 Bean shaped       (iii)                Present in abdomen on either side of the backbone (iv)               Basic unit is nephron. a.        Glomerulus- Group of capillaries (cluster) present in Bowman’s                            capsule to receive blood from renal artery and filters it. b.       Bowman’s capsule- Cup shaped structure, which contains glomerulus. c.         Convoluted tubule- is long and reabsorbs vital nutrients like glucose, amino acids, salts, urea and water.       F unctions of Kidneys- (a) Filtration & removal of N