Lesson 2 Flashcards
Any nutritious substance that people or animals, car or drink or plants absorb, in order to maintain life and growth.
Food
Is a complex set of organs, glands and ducts that work together to transform food into nutrients for cells
Digestive System
Functions of Digestive System:
is the consumption of solid or liquid food, usually through the mouth
Ingestion
Functions of Digestive System:
- is chewing
Mastication
Functions of Digestive System:
- is the movement of food from one end of the digestive tract to the other
Propulsion
Functions of Digestive System:
- is the movement of food back and forth
Mixing
Functions of Digestive System:
- is the breakdown of large molecules into smaller molecules that can be absorbed.
Digestion
Occurs through mechanical and chemical means
Digestion
Functions of Digestive System:
- is the addition of liquids, enzymes and mucus to the ingested food
Secretion
Functions of Digestive System:
is the movement of molecules out of the digestive tract and into the blood of the lymphatic system
Absorption
Functions of Digestive System:
is the removal of undigested material
Elimination
Digestive tract and gastrointestinal tract
Consists of:
The oral cavity
The pharynx
The esophagus
The stomach
The small and large intestine
The anus
What are the 3 specific associated organs of the digestive system?
Salivary glands
The liver
The pancreas
Empty into the oral cavity
Salivary glands
Empty into the small intestine
The pancreas
Four Major Tunics of the digestive tract
Mucosa
Submucosa
Muscularis
Serosa
The innermost tunic
Mucosa
Lies just outside the mucosa
Submucosa
Lies outside the submucosa
Muscularis
is the outermost layer of the digestive tract
Serosa
Is a continuous membrane which lines the abdominal cavity and covers abdominal organs
Peritoneum
Is a serous membrane that covers the organs
Visceral Peritoneum
Is a serous membrane that lines the wall of the abdominal cavity
Parietal Peritoneum
Is a general term referring to the serous membranes attached to the abdominal organs
Messentery
the messentery associated with the small intestine
Messentery Proper
The messentery connecting the lesser curvature of the stomach to the liver and diaphragm
Lesser Omentum
The messentery connecting the greater curvature of the stomach to the transverse colon and posterior body wall
Greater Omentum
are the muscular structures, formed mostly by the orbicularis Oris muscle
Lips
Outer surfaces are covered by skin
Lips
It forms the lateral walls of the oral cavity
Cheeks
Is a large muscular organ that occupies most of the oral cavity
Tongue
The anterior attachment of the tongue to the floor of the mouth by a thin fold of tissue
Frenelum
The hardest white outer part of the tooth
Enamel
Mostly made up of calcium phosphate
Enamel
A layer underlying the enamel
Dentin
The softer living inner structure of teeth
Pulp
A layer of connective tissue that binds the roots of the teeth firmly to the gums and jawbone
Cementum
Tissue that helps hold the teeth tightly against the jaw
Periodontal ligament
Each tooth consists of three regions:
Crown, Neck, Root
Visible portion of the tooth
Crown
Small region between the crown and the root
Neck
Anchors in it the bone of the maxillae and mandible
Root
“Roof” of the oral cavity
Palate
the anterior part and contains the bone
Hard palate
the posterior part and consists of skeletal muscle and connective tissue
Soft palate
A posterior extension of the soft palate
Uvula
are located in the lateral posterior walls of the oral cavity, in the nasopharynx, and in the posterior surface of the tongue
Tonsils
A normal adult mouth has?
32 teeth
The middle most four teeth on the upper and lower jaws
Incisors
The pointed teeth just outside the incisors
Canines
Teeth between the canines and molars
Premolars
Flat teeth in the rear of the mouth, best at grinding food
Molars
Erupt at around age 28 but often surgically removed to prevent displacement of other teeth
Wisdom teeth
A mixture of serous membrane fluids
Saliva
What are the 3 major pairs of salivary glands
Parotid glands, submandibular glands, sublingual glands
The largest of the salivary glands
Parotid glands
Produce more serous the mucous secretions
Submandibular glands
Smallest of the salivary glands
Sublingual glands
Or deglutition
Swallowing
Swallowing is divided into three phases:
The voluntary phase, The pharyngeal phase, The esophageal phase
Commonly known as “ Buccal Phase”
The voluntary phase
construction of the tongue to push up the bolus up
The voluntary phase
A rapid phase of muscle contraction to propel the bolus
The pharyngeal phase
An autonomous process not under voluntary control
The esophageal phase
The stomach is divided into 4 regions:
Cardia, Fundus, Body, Pylorus
The first part of the stomach
Cardia
Is a dome- shaped part of the stomach
Fundus
The main part of the stomach
Body
The largest part of the stomach
Body
Connects the stomach to the doudenum
Pylorus
It is the opening between the stomach and the small intestine
Pylorus
Is a very powerful sphincter
Pyloric sphincter
As food enters the stomach, the food mixed with stomach secretions to become a semifluid mixture
Chyme
4 substances of stomach
Hydrochloric acid, Pepsin, Mucus, Intrinsic factor
Kills microorganisms
Hydrochloric acid
Digest proteins found in indigested food
Pepsin
Forms a thick layer, which lubricates the epithelial cells of the stomach wall and protects them from the damaging effect of the acidic chyme and pepsin
Mucus
Binds with vitamin B12 and makes it more readily absorbed in the small intestine
Intrinsic factor
Major function of small intestine
Absorption of nutrients
How long does the small intestine?
6m long
Small intestine consists of 3 parts:
Duodenum, Jejunum, Ileum
The first part of the small intestine
Duodenum
Primary functions: to absorb sugars, amino acids, and fatty acids
Jejunum
Middle portion of the small intestine
Jejunum
Absorbs any remaining nutrients that did not get absorbed by the duodenum or jejunum
Ileum
The site where the ileum connects to the large intestine
Ileocecal junction
Secretions from the mucosa of the s. Intestine contain:
Mucus, ions and water
Two major enzymes groups of epithelial cells in the wall of S. Intestine
Peptidase, Disaccharidases
Digest proteins
Peptidases
Digest small sugars, specifically dissacharides
Disaccharidases
Largest internal organ of the body; located in the RUQ of the abdomen
Liver
Liver consists of 4 lobes:
Right lobe, left lobe, caudate lobe, quadrate lobe
A connective tissue septum that separates the left and right lobe
Falciform Ligament
2 sources that supplies blood to the liver:
Hepatic Artery, Hepatic portal vein
Delivers oxygenated blood to the liver
Hepatic artery
Carries nutrient- rich blood from the digestive tract to the liver
Hepatic portal vein
Liver 6 primary functions:
Bile production, Vitamin and mineral storage, detoxification of blood, helps metabolize proteins, absorption of bilirubin, albumin production
What are the 3 types in Bile production
Bile, bilirubin, bile salts
A complex solution that contains bile salts, bile pigments, cholesterol, lipids, lipid- soluble hormones, lecithin
Bile
A bile pigment which results from the breakdown of hemoglobin
Billirubin
Emulsify lipids
Bile salts
Is an extended, accessory digestive gland that is found retroperitoneally, crossing the bodies of the L1 and L2 vertebrae on the posterior abdominal wall
Pancreas
Lies transversely in the upper abdomen between the duodenum on the right and the spleen on the left
Pancreas
The stomach meets the first part of the small intestine
Head
Tapering part in the middle
Body
At the end of the pancreas
Tail
Are small islands of cells that produce hormones that regulate blood glucose levels (insulin and glucagon)
Pancreatic Islets or Islets of Langerhans
Functions in the pancreas
Exocrine pancreas and endocrine pancreas
Produces enzymes that help to digest food particularly protein
Exocrine pancreas
The major proteins digesting enzymes are:
Trypsin, chymotrypsin, carboxypeptidase
Digest starch for energy acquisition
Pancrealic amylase
Lipid- digesting enzyme
Lipase
Degrade DNA and RNA to their component nucleotides
Nucleases
Makes the hormone insulin, which helps control blood sugar levels
Endocrine Pancreas
The portion of the digestive tract extending from the ileocecal junction to the anus
Large intestine
4 parts of the Large Intestine
Cecum, Colon, Rectum, Anal Canal
Proximal end of the large intestine
Cecum
Attached to the cecum is a tube about 9cm long called?
Appendix
The Largest part of the large intestine
Colon
Is a straight muscular tube that begins of the termination of the sigmoid colonand ends at the canal
Rectum
Serves as a channel connecting the rectum to the end of the gastrointestinal system, the anus
Anal Canal
4 parts of the colon
The ascending colon, the transverse colon, descending colon, the sigmoid colon
Is the breakdown of food to molecules that are small enough to be absorbed into the blood
Digestion
Two types include in digestion:
Mechanical digestion, chemical digestion
Breaks large food particles into smaller ones
Mechanical digestion
Uses enzymes to break covalent chemical bonds in organic molecules
Chemical digestion
Begins in the stomach
Absorption
The simple molecules that result from chemical digestion pass through the cell membrane of the lining in the small intestine into the blood of lymph capillaries
Absorption
Requires carrier molecules and includes facilitated diffusion, co-transport and active transport
Transport
Forms the inner layer of the serous pericardium, also called epicardium
Visceral pericardium
Forms the outer layer of the serous pericardium
Parietal pericardium