Test 2 Flashcards
(73 cards)
Digestion
The mechanical and chemical breakdown of food into subunits so that nutrients can be absorbed
Digestive Tract
The central pathway of the digestive system; a long muscular tube that pushes food between the mouth and the anus
Esophagus
The section of digestive tract between the mouth and the stomach
Peristalsis
Coordinated muscular contractions that force food down the digestive tract
Stomach
An expandable muscular organ that stores, mechanically breaks down, and digests proteins in food
Small Intestine
The organ in which the bulk of chemical digestion and absorption of food occurs
Pancreas
An organ that helps digestion by producing enzymes (such as lipase) that act in the small intestine, and by secreting a juice that neutralizes acidic chime
Liver
An organ thataids digestion by producing bile salts that emulsify fats
Gall Bladder
An organ that stores bile salts and releases them as needed into the small intestine
Villi (Villus)
Fingerlike projections of folds in the lining of the small intestine that are responsible for most nutrient and water absorption
Large Intestine
The last organ of the digestive tract, in which remaining water is absorbed and solid stool is formed
Stool
Solid waste material eliminated from the digestive tract
Simple Diffusion
The movement of small, hydropohobic molecules across a membrane from an area of higher concentration to an area of lower concentration; simple diffusion does not require energy
Transport Proteins
Proteins involved in the movement of molecules across the cell membrane
Facilitated Diffusion
The process by which large or hydrophilic solutes move across a membrane from an area of higher concentration to an area of lower concentration with the help of transport proteins
Active Transport
the energy-requiring process by which solutes are pumped from an area of lower concentration to an area of higher concentration with the help of transport proteins
If a solute is moving through a phospholipid bilayer from an area of higher concentration to an area of lower concentration without the assistance of a protein, then the manner of transport must be…
Simple Diffusion
Sugars are large, hydrophilic molecules that are important energy sources for cells. How can they enter cells from an environment with a very high concentration of sugar?
By Facilitated Diffusion
What do simple diffusion and facilitated diffusion have in common?
Both involve the movement of a solute moving down a concentration gradient (from higher to lower concentration). In both cases additional energy is not required.
What do active transport and facilitated diffusion have in common?
Both facilitated diffusion and active transport require the function of a protein embedded in a membrane. However, the solute is moving in the opposite direction (relative to the concentration gradient) in these two cases.
Order of the structures of the digestive system:
Mouth, esophagus, stomach, small intestine, large intestine
Which part of the digestive tract has the most acidic pH?
Stomach
Gastric bypass surgery causes the ______ to become _________.
stomach, smaller
Where does the majority of chemical digestion take place?
small intestine
