UNIT-I
  HUMAN ANATOMY& PHYSIOLOGY-I
  *    This is the first unit which includes two important systems of human beings… i.e., Diges- tive system and Respiratory system.
  *    In the topic related to digestive system of human beings, elaborate explanation is given about the parts of alimentary canal like teeth, tongue, stomach, intestine etc.,
  *    Structure and functions of vital organ in our body i.e., Liver is given clearly.
  *    Various steps involved in the process of digestion are also given extensively.
  *    Disorders of digestive system are also given.
  *    In the topic of Breathing and exchange of gases, various parts of human respiratory system are explained.
  *    Detailed explanation is given about mechanism of breathing.
  *    Respiratory volumes and capaci- ties are given.
  *    Transportation   of gases and dis- orders of the respiratory system are explained finally.
 
  Important points for IPE:   Alimentary canal
 
  *    Parts of palate. Significance of palate. Role of uvula.
  *    Type of dentition is thecodont, heterodont and diphyodont.
  *    Dental formula in adult man is 2/2, 1/1, 2/2, 3/3.
  *    Dental formula of milk dentition is 2/2, 1/1, 0/0, 2/2.
  *    Parts of tooth are crown, neck and root.
  *    Odontoblasts secrete dentine and enamel is secreted by amelo blasts.
  *    Longitudinal section of tooth is important for SAQ.
  *    Taste buds on tongue in the form of three types of papillae like fungiform, filiform and circum- vallate papillae.
  *    Parts of pharynx are naso-pharynx, oropharynx and laryn-gopharynx.
  *    Three types of tonsils are pharyngeal/adenoids, palatine and lingual tonsils.
  *    Stomach has three major parts like cardiac, fundic and pyloric.
  *    Small intestine has duodenum, jejunum and ileum.
  *    Large intestine has caecum, colon and rectum.
  *    Colon has ascending, transverse and descending parts and a sigmoid colon. Colon has haustra.
  *    Anal canal opens out through anus which is guarded by internal anal sphincter with smooth muscle and external anal sphincter formed by striped muscle.
  Digestive glands.
  *    Three pairs of salivary glands are parotid, sub maxillary or subma-ndibular  and sublingual glands.
  *    Saliva contains the enzyme ptyalin or salivary amylase and lysozyme with pH 6.8.
  *    Gastric glands are present in the wall of stomach. Gastric juice contains proenzymes like pepsi nogen, prorennin, HCl and Castle's intrinsic factor. pH of gastric juice is 0.9 to 1.8.
  *    Intestinal glands are of two types like Brunner's glands and Crypts of Lieberkuhn. Their secretions make intestinal juice or succus- entericus with the pH of 7.5 to 8.0. It contains peptidases, disac- charidases, lipase and entero- kinase as enzyme activator.
  *    Largest gland is liver. It has two lobes which are made with  hexagonal hepatic lobules.
  *    Bile secreted by liver stores in gall bladder.
  *    Pancreas is the second largest gland in the body.  
  Physiology of digestion
  *    Conversion of complex and non-diffusible food substances into simple diffusible forms is known as digestion.
  *    Various phases of digestion in different parts of alimentary can-al are very important for IPE and other competitive examinations of state level and national level.
  *    Students practice the various steps in digestion of various components like carbohydrates, proteins, fats and nucleic acids of food in different parts of alimen- tary canal.
  *    They should know the role of various types of digestive enzymes at different level of digestion in sequence.
  *    End products of digestion are glucose, amino acids, fatty acids and glycerol.
  *    Peristalsis involves contraction of relaxation of smooth muscles of the wall of gut which result in successive wave like movements throughout the gut which causes propulsion of food through different parts of gut and its exposure to efficient enzymatic action.
  *    Entry of digested food into blood and lymph through intestinal mucosa to transport to cells is known as absorption. It is helped by passive, active and facilitated transport mechanisms.
  *    Gastrointestinal hormones are gastrin, enterogastrone, secretin, cholecystokinin and enterocrinin.
  *    Disorders of digestive system are jaundice, vomiting, diarrhea, constipation and indigestion.
  Breathing & exchange of gases:
  *    Respiratory system is a catabolic process of release of energy by the oxidation of food.
  *    Respiratory organs in different animals are   
      i)    sponges, cnidarians, flat wor- ms-body surface by diffu- sion.  
      ii)    earthworms-moist body wall.
      iii)    insects - tracheal system  
      iv)    spiders and scorpions - book lungs  
      v)    aquatic arthropods, mollusks - gills  
      vi)    terrestrial animals - lungs.
  *    Human respiratory system includes external nostrils, nasal chambers, naso-pharynx, larynx, trachea, bronchi and bronchioles and lungs.
  *    Larynx is voice box and supported by nine cartilages like unpaired thyroid, cricoid and epiglottis and paired cartilages like corniculate cartilages, aryte- noids and cuneiform cartilages.
  *    Rima glottidis is the space between the true vocal cords and arytenoids cartilages.
  *    Adam's apple is the laryngeal prominence in the mid ventral part of the thyroid cartilage.
  *    Trachea wind pipe which is supported by 'C' shaped in- complete hyaline cartilaginous rings. Formation of pulmonary tree is important for exams.