Slide #1 Heterotroph Nutrition • All the activities by which an organism obtains and uses food from the environment for growth and repair of cells • Ingestion-take in • Digestion-breakdown • Egestion-removal of waste Slide #2 Ingestion: Phagocytosis (solid) / Pinocytosis (liquid) Digestion: Lysosome enzymes in food vacuole Egestion: Exocytosis Types of Ingestion or Endocytosis: Pinocytosis (cell drinking) Process where cell membrane “pinches in” drawing molecules into the cell forming a pinocytic vesicle Phagocytosis (cell eating) Process where pseudopods of a cell flow around matter and engulf it forming a food vacuole. Pseudo= false and Pod = foot Pseudopod = false foot Slide #3 Phagocytosis Phagocytosis Requires ATP Energy Slide #4 Ingestion: Cilia beat food into oral groove and gullet forms food vacuole Digestion: Lysosome enzymes in food vacuole Egestion: Waste out anal pore Nutrients Slide #5 • The substances in food that an organism needs and uses for its life functions Slide #6 Function of Nutrients 1. They act as a fuel to provide energy for the life activities of cells 2. They supply chemicals needed for growth and repair of cells 3. They regulate proper functioning of the cell How do we get the nutrients we need to maintain life activities????? Slide #7 Alimentary Canal: (Extra-cellular Digestion) Tube within a tube body construction Mouth Pharynx Esophagus Stomach Small Intestine Large Intestine Rectum Anus Accessory Organs Salivary Glands Pancreas Liver Human Digestive system Slide #8 Pharynx Salivary Glands Esophagus Liver Gall Bladder Colon Large Intestine Appendix Anus Mouth Teeth/Tongue Stomach Pancreas Small Intestine Rectum Slide #9 Mouth & Pharynx: Click to enlarge Mechanical Digestion: - breaks foods into smaller pieces - increases surface area - chewing, grinding, crushing (tongue) Chemical Digestion: - salivary glands release amylase (starch maltose) (works best at pH 8) Note: Epiglottis covers opening of trachea Which type of digestion is the following? 1. Chewing a saltine? 2. Saliva breaking the saltine down into molecules of glucose? 3. Your tongue breaking pieces of a hamburger apart? 4. Pepsin (an enzyme) in your stomach breaking the hamburger into amino acids? Slide #10 Slide #11 Esophagus: - connects pharynx to stomach - peristalsis (wave of muscular contractions of alimentary canal) Stomach: (holds 2 liters of food) Mechanical Digestion – churning of stomach Chemical Digestion – glands Gastric Gland secretes acidic gastric juices (pH 2) contains HCl contains enzyme pepsin (proteins smaller polypeptides) Slide #12 Slide #13 What stimulates gastric juice flow? 1) thought, smell, sight, and taste 2) food entering the stomach 3) food touching stomach lining liquids pass through stomach in 20 minutes solids pass through in 2-6 hours Hunger pains are churning of empty stomach Ulcer caused by excess gastric juice digesting part of stomach wall Slide #14 Gastric Bypass Surgery Small Intestine Small Intestine: - Length = 6.5 meters - Diameter = 2.5 cm - pH 8 Functions: Chemical Digestion (most) Absorption of Nutrients Peristalsis: moves food through intestine mixes food with enzymes mechanical digestion speeds up absorption Slide #15 Small Intestine Slide #16 Slide #17 Liver Food mixes with: • Bile from liver Gallbladder • Pancreatic juices from pancreas (*enzymes*) • Intestinal juices from intestinal glands (*enzymes*) Bile: - produced by liver - stored in gallbadder - released into upper small intestine Function: Emulsification of fats (break into droplets) Neutralizes acidic contents from stomach Small Intestine Absorption: Slide #18 Circulatory System uses (CAPILLARIES) to absorb:: • simple sugars (glucose) • amino acids • vitamins • minerals Slide #19 Adaptations that increase surface area of intestine: Length (6.5 meters or 21 feet) Lining has folds Villi (finger-like projections on folded lining) Absorption involves diffusion and active transport Slide #20 Regent’s Practice • A. B. C. D. The pancreas is an organ connected to the digestive tract of humans by a duct through which digestive enzymes flow. These enzymes are important to the digestive system because they: Form proteins needed in the stomach Form the acids that break down food Change food substances into molecules that can pass into the bloodstream and cells Change food materials into wastes that can be passed out of the body. Large Intestine: Colon Slide #21 Length = 1.5 meters Diameter = 6 cm No digestion occurs here Function: • Absorption of water - Diarrhea (too little absorption) - Constipation (too much absorption) • Bacteria produce vitamin K and various vitamin B Note: Appendix is attached between small and large intestine (vestigial organ) Slide #22 the quest for Polyps • Colonoscopy: Slide #23 Large Intestine ( Colon Polyps_) • Polyps are small growths on the inner colon lining that look like warts. Slide #24 Removal Colon Polyps_) You may be more likely to get colon polyps if you: •eat a lot of fatty foods •smoke •drink alcohol •don’t exercise •weigh too much Rectum: Slide #25 • temporary storage of feces (stool) • feces is primarily undigested material Anus: (anal sphincter) • releases waste into environment (egestion/defecate) Slide #26 End Products of Digestion (Hydrolysis) Proteins Carbohydrates glucose Lipids fatty acids + glycerol amino acids Slide #27 Regent’s Practice • Organic compounds, such as proteins and starches, are too A to diffuse into cells. Proteins are digested to B and starches are digested to C. A. A- large, B-simple sugars, C- amino acids B. A- small, B-simple sugars, C-amino acids C. A-large, B-amino acids, C-simple sugars D. A-small, B-amino acids, C-simple sugars Slide #28 Disorders of the Digestive Tract Body Atlas: Digestive Problems Heartburn Slide #29 • ACID from the stomach backs up into the esophagus. Slide #30 Constipation To much water is absorbed by the large intestine. Also can exist due to lack of roughage. Results in solid/hardened stool Slide #31 Diarrhea Decreased water absorption and increased peristaltic activity of large intestine. Results in an increased watery feces. Gallstones Slide #32 An accumulation of hardened cholesterol deposits in the gall bladder. Can either be “passed” (OUCH!!) or surgically removed Slide #33 Nutritional Requirements • RDA- recommended daily allowance • intake level of a nutrient considered sufficient Slide #34 Nutritional requirements vary with individuals: age sex height weight activities Recommended Daily Calories For Men Slide #35 Middle Age Group With Moderate Activity : 5'4 119-155 2,548 5'5 133-160 2,596 5'6 127-164 2,644 6'0 151-193 2,932 6'1 155-198 2,980 6'2 159-203 3,028 5'7 5'8 5'9 5'10 6'3 6'4 6'5 6'6 131-169 135-174 139-179 143-184 2,692 2,740 2,788 2,836 5'11 147-188 2,884 163-208 167-212 171-217 175-222 3,076 3,124 3,172 3,220 Recommended Daily Calories For Women Slide #36 Middle Age Group With Moderate Activity : 4'11 90-120 2,100 5'0 93-124 2,133 5'1 97-128 2,177 5'2 100-132 2,210 5'3 104-137 2,254 5'4 107-140 2,287 5'5 111-145 2,331 5'6 114-149 2,364 5'7 118-154 2,408 5'8 121-157 2,441 5'9 125-162 2,485 5'10 128-166 2,518 5'10 128-166 2,518 5'11 132-170 2,562 6'0 135-174 2,595 6'1 139-178 2,639 6'2 142-182 2,672 Fast Food Nutritional Info Slide #37 Whopper w.Cheese Vanilla Shake – Super Size Fries Diet Coke Supposed to be: 760 CAL. small 360 CAL 540 CAL 0 CAL 1660 CAL Fast Food Nutritional Info Regular Slice Cheese Pizza Slide #38 380 Cal Regular Slice Sausage Pizza 495 Cal Regular Slice Pepperoni Pizza 427 CAL Supposed to be: 1302 CAL Click to return