Digestion Food: The easiest thing you will pass in school

Table 41.2

Table 41.1

Figure 41.5 Mechanical digestion Chemical digestion (enzymatic hydrolysis) Nutrient molecules enter body cells Undigested material EliminationAbsorptionDigestionIngestion1234

Liver Salivary glands Gall- bladder Esophagus Pharynx Oral cavity Sphincter Tongue Pancreas Small intestine Large intestine Rectum Anus Sphincter Stomach Duodenum of small intestine Figure 41.9a

Figure 41.9b Mouth Stomach Esophagus Pancreas Schematic diagram Anus Rectum Large intestine Small intestine Liver Salivary glands Gall- bladder

Tongue Pharynx Glottis Larynx Bolus of food Epiglottis up Esophageal sphincter contracted Esophagus To lungsTo stomach Trachea Figure

Tongue Pharynx Glottis Larynx Bolus of food Epiglottis up Esophageal sphincter contracted Esophagus To lungsTo stomach Trachea Figure

Tongue Pharynx Glottis Larynx Bolus of food Epiglottis up Esophageal sphincter contracted Esophagus To lungsTo stomach Relaxed muscles Contracted muscles Sphincter relaxed Stomach Trachea Figure

Gastric gland Gastric pits on interior surface of stomach Sphincter Small intestine Epithelium Mucous cell Chief cell Parietal cell Chief cell Pepsinogen Parietal cell Pepsin Folds of epithelial tissue Sphincter Esophagus Stomach  m HCl HH Cl  Figure 41.11

Figure 41.19a Liver Gallbladder Food Stomach Duodenum of small intestine Gastric juices Pancreas 1 Gastrin Key Stimulation Inhibition   

Figure 41.19b Bile Chyme CCK HCO 3 , enzymes Secretin Key Stimulation Inhibition 2 CCK     

Figure 41.19c Secretin and CCK Gastric juices 3 Key Stimulation Inhibition   

Figure Transport of glucose into body cells and storage of glucose as glycogen Breakdown of glycogen and release of glucose into blood Homeostasis: 70–110 mg glucose/ 100 mL blood Stimulus: Blood glucose level drops below set point. Pancreas secretes glucagon. Stimulus: Blood glucose level rises after eating. Pancreas secretes insulin.

Figure 41.13a Vein carrying blood to liver Muscle layers Villi Intestinal wall Large circular folds Key Nutrient absorption

Key Nutrient absorption Blood capillaries Epithelial cells Villi Microvilli (brush border) at apical (lumenal) surface Epithelial cells Lumen Basal surface Lacteal Lymph vessel Figure 41.13b

Figure LUMEN OF SMALL INTESTINE Triglycerides Epithelial cell Fatty acids Mono- glycerides Triglycerides Chylomicron Phospho- lipids, cholesterol, and proteins Lacteal

Figure Satiety center Ghrelin Insulin Leptin PYY    

Fat digestionNucleic acid digestion Protein digestion Fat (triglycerides) DNA, RNA Nucleotides Pancreatic nucleases Pancreatic lipase Glycerol, fatty acids, monoglycerides Nucleotidases Nucleosides Nucleosidases and phosphatases Nitrogenous bases, sugars, phosphates Amino acids Dipeptidases, carboxy- peptidase, and aminopeptidase Small peptides Pancreatic carboxypeptidase Smaller polypeptides Pancreatic trypsin and chymotrypsin Small polypeptides Proteins Pepsin Carbohydrate digestion PolysaccharidesDisaccharides Salivary amylase Smaller polysaccharides Maltose Pancreatic amylases Disaccharides Disaccharidases Monosaccharides Small intestine (enzymes from epithelium) Small intestine (enzymes from pancreas) Stomach Oral cavity, pharynx, esophagus Figure