Chapter 20: Digestive System Chapter 21: Urinary System
Functions of Digestion Ingest food Break down food in to small molecules: Mechanical digestion- Chemical digestion – Absorption Elimination
Carbohydrates Include sugars and their polymers Monomer is the monosaccharide Include 3 – 7 carbons with the –OH group being present on each carbon except one, which is double bonded to an oxygen (carbonyl group)
Lipids A group of polymers that have one characteristic in common, they do not mix with water. They are hydrophobic. Some important groups are fats, phospholipids, and steroids.
D. Stomach Stores food and digests protein Rugae – folds inside stomach Ulcers
Stomach Continued Gastric Juice – produces Chyme Pepsin – enzyme that digests protein HCL – kills bacteria, breaks down food, Intrinsic factor – absorption of B12. Mucous – softens food Gastrin – hormone that causes gastric juice to be released.
E. Small IntestineSmall Intestine Function- receives secretions from the liver, pancreas and absorption of nutrients. Lined with Villi – furry looking, absorption, increase surface area
F. Large IntestineLarge Intestine Function – absorb water, produce feces E.coli bacteria present
Disorders of Large Intestine Diarrhea – Constipation – Appendicitis – Diverticuloisis – colon cancer Colonoscopy
Part 2: Digestive System Accessory organs – food does not pass through
1. Pancreas Secretes Sodium Bicarbonate and enzymes to digest carbohydrates, proteins, and fats
2. Liver – Largest gland Storage of glucose as glycogen Destruction of old red blood cells – this creates bilirubin Production of bile Plasma proteins Detoxification of blood Storage of iron and other vitamins
Liver Lobule Anatomy Functional unit of the liver. Blood travels from small intestine – hepatic portal vein – to various liver lobules.
Kidney Function – filter blood that has collected wastes from cells. A. Excrete waste – urea, uric acid, creatine, ammonium B. Maintain blood volume – regulating water excretion C. monitor electrolytes in blood D. monitor blood pH E. secrete Renin – enzyme to help maintain blood pressure F. stimulates red blood cell production