Digestive System Flashcards
What are the main functions in the digestive system?
- ingest food
- digest food to nutrients
- eliminate indigestible remains
What is the digestive tract?
a long tube that begins in the mouth and ends in the anus
Digestion is broken into two types; which?
Mechanical & chemical
What does the mechanical part of digestion consist of?
chewing and mixing it in the stomach
What does the chemical part of digestion consist of?
enzymes break down macromolecules into small organic molecules
What are taste buds?
sensory receptors on the tongue that are activated by the presence of food
Identify the parts of the mouth
How many teeth do humans have as babies and as adults?
20 as baby and 32 as adults
How many parts is a tooth divided into?
Two: root & crown
Identify the parts of a tooth
What happens in the pharynx?
- Receives food from the mouth
- Swallowing happens here as an involuntary action
What does the epiglotis do?
Covers the entrance to the larynx (glotis) when food passes so it doesn’t go to the trachea
What is the esohpagus and what are its functions?
It is the muscular tube that passes from the pharynx through the thoracic cavity and diaphragm, in order to join the stomach.
Its function is to push food from the mouth into the stomach
What is peristalsis?
rythmic contraction of the smooth muscle in the digestive system that pushes food along the tract
What is the sphincter?
muscle that encircles a tube & acts as a valve
Which are the four layers of the digestive tract’s wall?
- Mucosa
- Submucosa
- Muscularis
- Serosa
What are the functions of the stomach?
- Store food
- Start the digestion of proteins
- Move food into small intestine
Identify the different parts of the stomach
How long (in average) is the small intestine?
6 meters long
What happens in the small intestine?
It receives bile from the liver and pancreatic juices from the pancreas
Whats does bile do?
digests fat
Identify the different parts of the small intestine (duodenum)
How does the large intestine help maintain homeostasis?
By ridding the body of indigestible remains
Identify the parts of the large intestine:
Which are the three accesory organs of the digestive system?
- Pancreas
- Liver
- Gallbladder
What does the endocrine part of the pancreas do?
secretes insulin & glucagon to keep glucose levels within limits
What does the exocrine part of the pancreas do?
neutralizes the acid in the stomach
What is produced in the endocrine tissue of the pancreas?
insulin & glucagon
What does insulin do?
lowers the levels of glucose in the body
What does glucagon do?
stimulates the liver to break down glycogen into glucose & raises the glucose levels
What are the main functions of the liver?
- detoxifying the body
- processing everything
- storing iron & some vitamins
What does the gallbladder do?
stores any excess of bile
Identify the different parts of the digestive tract
What are stomach ulcers?
open sores in the stomach wall, caused by gradual disintegration of the tissue
Which bacteris may cause a stomach ulcer and other diseases?
Helycobacter pylori
What is gastritis?
the inflammation of the lining of the stomach
What is colitis?
the inflammation of the colon (large intestine)
What is diarrhea?
when the large intestine’s wall becomes irritated, peristalsis increases, and less water is absorbed
What is hepatitis?
the inflammation of the liver
Which are the three types of hepatitis?
- Type A: water, food
- Type B: sexual contact, transfusion, needles
- Type C: chronic, liver cancer
When does cirrhosis occur?
when the liver becomes infiltrated with fat
What is diabetes?
no production of insulin, or cannot use insuline properly
What does diabetes affect?
the ability to regulate glucose metabolism
What happens, in general, in diabetes?
The body does have sugar, but the cells are starving, so they start metabolizing fat
