Presentation on theme: "Presented By: Sam Lund, Donovan Parker, Tom Srebernak"— Presentation transcript:
1 Presented By: Sam Lund, Donovan Parker, Tom Srebernak The Digestive SystemPresented By: Sam Lund, Donovan Parker, Tom Srebernak
2 Goals of the Digestive System 1. Extract nutrients from food2. Transform nutrients into useful formsEx. Oreo= Glucose (sugar)3. Absorb nutrients and distribute them where they are needed
3 Functions of the Digestive System Ingestion: Intake of nutrientsDigestion: Breakdown of large particles into smaller onesAbsorption: Uptake of nutrient moleculesDefecation: Elimination of undigested residues
4 Actions of the Digestive System 1. IntakeBreaks up foodMoves food through the GI tract (Peristalsis)Mixes with digestive enzymes2. SecretionRelease of enzymes and hormones for chemical digestion and regulation3. Membrane Transport- Absorption of nutrients from the tissues by the blood and lymph for transport
5 Stages of Digestion Mechanical: Physical breakdown of food Chemical: Digestive enzymes hydrolyze food particles to break larger molecules into smaller onesSome nutrients are absorbed without digestionVitamins, minerals, cholesterol, water
6 Anatomy of the Digestive System Oral CavityPharynxEsophagusStomachSmall IntestineLarge Intestine
7 Small Intestine 6 meters in length Functions: Chemical Digestion Nutrient AbsorptionNutrient Transportation
8 Functions of the Small Intestine Digestion and absorption of foodDigestive enzymes secreted by the pancreasEnter the small intestine via the pancreatic duct.
9 Anatomy of the Small Intestine Duodenum (25 cm)Food mixes with bile from the gallbladder.Jejunum (2.5m)Absorbs nutrients into the bloodstream.Ileum (3.6 m)Reabsorbs bile acids.
10 Large Intestine 1.5 meters long Responsible for absorption of water from the indigestible residue of food
11 Anatomy of the Large Intestine Ascending Colon: Descending Colon: Up the right side Down the left side Cecum: Sac on Sigmoid Colon: lower right side S-shaped
12 Anatomy of the Large Intestine Ascending Colon-Removes water and other nutrientsTransverse Colon-Expulsion of waste materials, continues leaching outDescending Colon-Absorbs water from fecal matter. Stores food particles that are to be emptied into the rectum.Sigmoid Colon- Make and eliminate feces. Contains 60 varieties of bacteriaRectum- Temporary storage for fecal matter before it’s eliminated from the body through the anal canal.
13 Oral Cavity Functions: A. Ingestion: Cheeks lips and tongue mobilize foodB. Digestion:MechanicalMasticationChemical3 salivary glandsDigests some starches and fat
14 PharynxPurpose: Pharyngeal constrictors force food down during swallowingDivided into 3 parts:EpipharynxMesopharynxHypopharynx
15 Esophagus Straight Muscular tube about 1 foot long Purpose: Muscular contraction moves food towards stomach
16 Stomach Food storage Mechanical digestion Chemical digestion Muscular sac on the left side of the peritoneal cavityFunctions:Food storageMechanical digestionChemical digestion
17 Enzymes Involved in Chemical Digestion Saliva:Amylase: Breaks down starchLipase: Breaks down fats when it enters the stomachStomach:HCL: Activates enzymes, breaks up foodsPepsin: Digests proteinsRenin: Digests milk
18 Final Destinations of Digestion Products Starches bloodstreamFats lymph vessels (lacteals)Proteins bloodstream