human digestion. human digestive system (general plan) accessory digestive organs
DESCRIPTION
Organ/s Mechanical digestion Carbohydrate digestion Protein digestion Nucleic Acid digestion Lipid digestion Oral cavity Esophagus Pharynx Chewing Peristalsis StomachChurning Mixing Peristalsis Small intestine Lumen Peristalsis Mixing Small intestine Epithelium Polysaccharides (starch, glycogen) Polysaccharides (starch, glycogen) Disaccharides (sucrose, lactose) Disaccharides (sucrose, lactose) Salivary amylase Smaller polysaccharides, maltose Smaller polysaccharides, maltose Polysaccharides Pancreatic amylase Maltose and other disaccharides Disaccharidases Monosaccharides Proteins Pepsin Small polypeptides Pancreatic trypsin and chymotrypsin Smaller polypeptides Small peptides Dipeptidases, carboxypeptidase, aminopeptidase Amino acids DNA, RNA Pancreatic nucleases Nucleotides Nucleotidases Nucleosides Nucleosidases, phosphatases Nitrogenous bases, sugars, phosphates Nitrogenous bases, sugars, phosphates Fat globules Bile salts Fat droplets Pancreatic lipase Glycerol, fatty acids, glycerides Glycerol, fatty acids, glycerides Sites of digestionTRANSCRIPT
Human digestion
Human digestive system (General plan)
Accessory digestive organs
Organ/s Mechanical digestion
Carbohydrate digestion Protein digestion
Nucleic Acid digestion
Lipid digestion
Oral cavityEsophagusPharynx
ChewingPeristalsis
Stomach ChurningMixingPeristalsis
Small intestineLumen
PeristalsisMixing
Small intestineEpithelium
Polysaccharides(starch, glycogen)
Disaccharides(sucrose, lactose)
Salivary amylaseSmaller polysaccharides,
maltose
Polysaccharides
Pancreatic amylaseMaltose and other
disaccharides
Disaccharidases
Monosaccharides
Proteins
PepsinSmall polypeptidesPancreatic trypsin and chymotrypsin Smaller polypeptides
Small peptidesDipeptidases,
carboxypeptidase,
aminopeptidase Amino acids
DNA, RNA
Pancreaticnucleases
Nucleotides
NucleotidasesNucleosides
Nucleosidases, phosphatasesNitrogenous
bases,sugars,
phosphates
Fat globules
Bile saltsFat droplets
Pancreatic lipaseGlycerol, fatty
acids, glycerides
Sites of digestion
• Salivary glands– Water– Some enzymes• Salivary amylase• Lysozyme
– Mucus or mucin• Teeth
Digestion in the Mouth
Swallowing: from mouth to stomach
Muscular sac◦ Churns & mixes food
Gastric glands◦ Parietal cells HCl,
intrinsic factor◦ Goblet cells
mucus◦ Chief cells
pepsinogen, weak gastric lipase
◦ Gastrin Hormone Controls gastric juices
Comes out as chyme (2-6 hours)
Digestion in the Stomach
LiverSecretes bile (stored in gall bladder)Emulsifies fats
GallbladderStores, concentrates, and
releases bile into duodenum
Stimulated by the hormone cholecystokinin (CCK)
• Exocrine function• Acinar cells secrete
pancreatic juice– Amylase– Lipase– Trypsin– Chymotrypsin– Carboxypeptidase– Nuclease– NaHCO3
• Secretin and cholecystokinin (CCK) fr intestinal wall stimulates PJ production
Pancreas
Absorption in the small intestine
Reabsorption and elimination in the large intestine
• Areas of the colon• cecum • rectum • anus
• Absorption of water and electrolytes
• Concentration & elimination of solids
• Home for bacteria• folic acid• vitamin K• several B-vitamins• gases
