Module 2.1 (BIOD 121 - Nutrition) Latest Update Graded A+

Module 2.1 (BIOD 121 - Nutrition) Latest Update Graded A+ Once absorbed, how can nutrients be used? - ANSWER-To fuel cellular growth, fight infections, and provide energy to our muscles and brain Peristalsis - ANSWER-Involuntary muscle contractions that move food through the digestive system. Enzymes - ANSWER-Proteins that catalyze chemical reactions Mucosa - ANSWER-The innermost layer of the human digestive tract Passive diffusion - ANSWER-The movement of substances across cell membranes from higher concentration to lower concentration without the use of energy. Facilitated diffusion - ANSWER-The movement of substances across cell membranes from higher concentration to lower concentration assisted by specific transport proteins. Active transport - ANSWER-The movement of substances across cell membranes from lower concentrations to higher concentrations assisted by specific transport proteins and ATP; includes endocytosis Four organs that produce and secrete substances that aid in digestion - ANSWER-Salivary glands, liver, gallbladder, and the pancreas Saliva - ANSWER-Mucus and enzymes Enzymes in the mouth - ANSWER-Salivary amylase (starches) and lingual lipase (fats) Epiglottis - ANSWER-A flap of tissue that seals off the windpipe and prevents food from entering Gastric juice - ANSWER-Acids and enzymes in the stomach: pepsin (protein) and gastric lipase (fat) Chyme - ANSWER-Food particles, enzymes, and stomach acid; empties into the small intestine through the pyloric sphincter over 1-4 hours Gastrin - ANSWER-The hormone responsible for controlling the concentration of acid in the stomach Intrinsic factor - ANSWER-A glycoprotein produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12 Parts of the small intestine - ANSWER-Duodenum, jejunum, ileum Villi - ANSWER-Fingerlike extensions of the intestinal mucosa that increase the surface area for absorption Role of the liver - ANSWER-Secretes bile Role of the gallbladder - ANSWER-Stores biles until fat enters the small intestine; bile is released into the duodenum through the common bile duct. Role of the pancreas - ANSWER-Releases pancreatic juices (water, bicarbonate, and enzymes), glucagon (increases blood sugar), and insulin (decreases blood sugar) Ileocecal sphincter - ANSWER-Controls the flow from the ileum of the small intestine into the cecum of the large intestine Parts of the large intestine/colon - ANSWER-Ascending, transverse, descending, and sigmoid colon Role of the large intestine - ANSWER-Absorbs water and any remaining nutrients, produces and stores feces Role of mucus in the large intestine - ANSWER-Holds feces together, breaks down fiber, and protects against harmful bacteria Probiotics - ANSWER-Foods that contain lactobacilli and bifidobacterium Prebiotics - ANSWER-Nutrients that encourage the growth of beneficial microbes in the intestine