Digestive to Urinary System

Digestive system/Alimentary tract

provides the body with the nutrients, water and electrolytes essential for health. The organ of this system ingests, digest and absorb food and eliminate the undigested remains as feces.

Digestive system

consists of a hollow tube extending from the mouth to the anus, into which various accessory organs or glands empty their secretions

Alimentary canal

outside the body because it has contact only with the cells lining the tract

digestion

must first be broken down physically (by chewing) and chemically (by enzymatic hydrolysis) into its smaller diffusible molecules – a process called ___________

absorption

digested end products can then pass through the epithelial cells lining the tract into the blood for distribution to the body cells – a process termed _____________

alimentary canal/gastrointestinal (GI) tract and accessory digestive organs

organs of the digestive system are traditionally separated into two major groups:

9

alimentary canal is approximately ____ meters long in a cadaver but is considerably shorter in a living person due to muscle tone

ALIMENTARY CANAL

It consists of the mouth, pharynx, esophagus, stomach, and small and large intestines

accessory structures

__________ include the teeth, which physically breakdown foods, the salivary glands, gall bladder, liver and pancreas, which secrete their products into the alimentary canal

MUCOSA (Mucous membrane), SUBMUCOSA, MUSCULARIS EXTERNA, SEROSA

FOUR BASIC TUNICS (layers):

MUCOSA (MUCOUS MEMBRANE)

wet epithelial membrane surrounding the alimentary canal lumen. major functions are secretion, absorption of digested food stuff and protection against bacterial invasion.

MUSCULARIS MUCOSAE

scant layer of smooth muscle fibers that enable local movements of the mucosa

SUBMUCOSA

moderately dense connective tissue containing blood and lymphatic vessels, scattered lymphoid follicles and nerve fibers. Its vessels absorb and transport nutrients, and its abundant elastic fibers help maintain the normal shape of each organ

MUSCULARIS EXTERNA

typically is a bilayer of smooth muscle, with the inner layer running circularly and the outer layer running longitudinally. This layer moves the contents of the canal along by segmentation and peristalsis. An important intrinsic nerve plexus, the myenteric plexus, associated with this tunic is the major regulator of GI motility.

SEROSA

outermost covering of the intraperitoneal organs which is also called the visceral peritoneum. It consists of mesothelium associated with a thin layer of areolar connective tissue. reduces friction as the mobile digestive system organs work and slide across one another and the cavity walls. In the esophagus, which is outside the abdominopelvic cavity, it is is replaced by an adventitia, a layer of coarse fibrous connective tissue that binds the organ to surrounding tissues.

Mouth/Oral Cavity/Buccal Cavity

Foods enter the digestive tract through ___________. Within this mucous membrane-lined cavity are the gums, teeth, tongue and openings of the salivary glands.

lips (labia)

__________ protect the opening of the chamber anteriorly, the cheeks form its lateral walls, and the palate form its roof

hard palate

The anterior portion of the palate is referred to as the ___________ because the palatine processes of the maxillae and horizontal plates of the palatine bones underlie it.

soft palate

posterior __________ is a fibromuscular structure that is unsupported by bone

uvula

The ______, a finger-like projection of the soft palate extends inferiorly from its posterior margin

lingual frenulum

A membrane called the ___________ secures the inferior midline of the tongue to the floor of the mouth.

oral vestibule

space between the lips and the cheeks and the teeth and gums is the ____________

oral cavity proper

the area that lies within the teeth and gums is the _________________

TEETH

one of the hard calcified structures set in the alveolar processes of the jaws for biting and mastication of food

TONGUE

a muscular organ attached to the floor of the mouth. It is the chief organ of taste and aid in mastication, swallowing and speech

SALIVARY GLANDS

three pairs of glands whose combined secretions constitute the saliva

Parotid Gland, Sublingual Gland, Submandibular/Sub-maxillary gland

THREE PAIRS OF SALIVARY GLANDS:

Parotid Gland

largest among the salivary glands that lies immediately inferior and anterior to the external ear which has a duct that opens into the oral vestibule opposite the second upper molar called the “Stensen’s duct”

Sublingual Gland

is composed of a group of smaller glands which is narrow and elongated in form which has also a duct that opens beside the orifice of the Wharton’s duct called the “Bartholin’s duct”/ “Duct of Rivinus”

Submandibular/Sub-maxillary gland

is irregularly shaped, fairly large that extend posteriorly from a point below the first molar almost to the angle of the mandible. It also has a duct which is known as the “Wharton’s duct”.

Pharynx/Throat

When the tongue initiates swallowing, food passes posteriorly, a common passageway for food, fluid and air

NASOPHARYNX, OROPHARYNX, LARYNGOPHARYNX

pharynx is subdivided anatomically into three parts:

inner layer of longitudinal muscle and outer layer of circular constrictor muscles

wall of the pharynx consists largely of two layers of skeletal muscles:

Esophagus or Gullet

extends from the pharynx through the diaphragm to the gastro-esophageal sphincter in the superior aspect of the stomach. Approximately 25 centimeters (10 inches) long in humans, it is essentially a food passageway that conduct food to the stomach in a wavelike peristaltic motion

gastroesophageal sphincter

a slight thickening of the smooth muscle layer at the esophago-gastric junction, controls food passage into the stomach

Stomach

a pear-shaped organ situated between the end of the esophagus and the beginning of the small intestine. It is located on the left side of the abdominal cavity and is hidden by the liver and diaphragm.

Magenblase

When the stomach is empty it is collapsed except for the upper part which usually contains air called the __________ (a stomach bubble which is represented by a dark area above the upper part of the stomach).

cardiac part/cardia

____________ is the area surrounding the cardiac orifice through which food enters the stomach.

fundus

__________ is a dome-shaped portion of the stomach found super laterally to the cardia.

pyloric antrum

The wide superior area of the pyloric part is called the ______________

pylorus

___________ is continuous with the small intestine through the pyloric sphincter or valve

Sphincter

________ is a thickened ring of involuntary muscle encircling an opening in a hollow organ to keep the opening closed.

CARDIAC ORIFICE, PYLORIC ORIFICE

Two Openings of the Stomach:

Cardiac Orifice

is on the medial border close to the upper end of the stomach where the esophagus and stomach meet. The cardiac opening has a sphincter called “Cardiac sphincter”.

_____________ is at the lower end of the stomach where the small bowel or small intestine continuous from this opening. It has a sphincter called “Pyloric sphincter” that controls food movement into the small intestine from the stomach and prevents the S.I. from being overwhelmed

lesser curvature

The concave medial surface of the stomach is called the _______________ which is the shorter, concave right border.

greater curvature

Its convex lateral surface is the ____________- which is the longer, convex left border.

omenta/omentum

Extending from these curvatures are two mesenteries, called ______________

lesser omentum

____________ extends from the liver to the lesser curvature of the stomach

greater omentum

The ___________ a saclike mesentery, extends from the greater curvature of the stomach, reflects downward over the abdominal contents to cover them in an apron-like fashion

Incisura Angularis

____________ is the sharp bend on the lesser curvature below its midpoint.

RUGAE

The Stomach has a lining membrane which forms a longitudinal fold that partly disappear when the stomach is full called the _______

Small Intestine

a convoluted tube, 6-7 meters (about 20 feet) long in a cadaver but only about 2 meters (6 feet) long during life because of its muscle tone. It extends from the pyloric sphincter to the lleo-cecal valve

DUODENUM, JEJUNUM, ILEUM

Three Parts of the Small Intestine:

Duodenum

is the first 25 centimeters (10 inches) of the Small Intestine which form a double loop. It extends from the pyloric sphincter and curves around the head of the pancreas; most of the duodenum lies in a retroperitoneal position

SUPERIOR DUODENUM, DESCENDING DUODENUM, TRANSVERSE DUODENUM, ASCENDING DUODENUM

Four Parts of the Duodenum:

Superior Duodenum

is the first part of the duodenum that extends up and to the (R) including the duodenal cap or bulb.

Descending Duodenum

passes downward to the (R) where the Common Bile Duct (CBD) opens into it.

Transverse Duodenum

passes to the (L) across the midline.

Ascending Duodenum

passes up behind the stomach to join with the Jejunum.

Jejunum

continuous with the duodenum, extends for 2.5 meters (about 8 feet) long. Most occupies the umbilical region of the abdominal cavity.

Ileum

the terminal portion of the small intestine, is about 3.6 meters (12 feet) long and joins the large intestine at the ileo-cecal valve. It is located inferiorly and somewhat to the right in the abdominal cavity, but its major portion lies in the hypogastric region.

Ileocecal sphincter

Ileo-Cecal junction has a sphincter called the ____________-

Large Intestine/Colon

is about 1.5 meters (5 feet) long and extends from the lleo-cecal junction to the anus. It forms an inverted “U” shaped structure that passes up from the (R) lower abdomen to the (R) upper abdomen. It descend to the (L) lateral abdomen to the pelvis.

CECUM, ASCENDING CECUM, HEPATIC FLEXURE/R COLIC, TRANSVERSE COLON, SPLENIC FLEXURE/L COLIC, DESCENDING COLON, SIGMOID/PELVIC COLON, RECTUM, ANAL CANAL

COLON IS DIVIDED INTO 9 PARTS:

Cecum

is that part of the colon that forms a pouch below the ileo-cecal junction. Its lower end is rounded and closed except an opening to the appendix where it is attached

Vermiform Appendix

____________ varies in length from 2-6 inches in length. It usually lies below the cecum but may also lie behind, medial or lateral to the cecum

Ascending Colon

__________ passes up from the Cecum to the under surface of the liver anterior to the (R) kidney.

Hepatic Flexure/(R) Colic

____________ is a bend of the colon to the (L) under the (R) liver surface.

Transverse Colon

______________ passes across the upper abdomen from the hepatic flexure to the spleen in the (L) upper abdomen.

Splenic Flexure / (L) Colic

_____________ is a bend of the colon where the transverse colon ends.

Descending Colon

_____________ extends down from the splenic flexure to the brim of the pelvis in the (L) lateral abdomen.

Sigmoid/Pelvic Colon

is the “S” shaped curved part of the distal colon extending from the descending colon to the rectum.

Rectum

is the final part of the colon that extend from the sigmoid to the anus.

Anal Canal

is the lower 1 ½ inch of the rectum and ends at an opening--- the “anus.”

voluntary external anal sphincter, involuntary internal anal sphincter

anal canal has two sphincters, a ______________ composed of skeletal muscle, and an ______________ composed of smooth muscle.

tenia coli

In large intestine, the longitudinal muscle layer of the muscularis externa is reduced to three longitudinal muscle bands called the ___________

HAUSTRA

are the puckered folds of the colon caused by the arrangement of the longitudinal muscle called the “Tenia Coli”. They are sacculation in the wall of the colon produced by the adaptation of its length to the Tenia Coli.

PANCREAS/PANCREATIC GLAND, LIVER, GALL BLADDER

Accessory Organs of Digestion:

PANCREAS or PANCREATIC GLAND

is a long tapering structure that lies transversely in the upper posterior abdomen behind the duodenum and stomach. Like the duodenum, it is a retroperitoneal organ

HEAD OF PANCREAS, BODY OF PANCREAS, TAIL OF PANCREAS

PARTS OF THE PANCREAS:

Head of the Pancreas

blunt, rounded which lies in the curve of the duodenum or C-loop

Body of the Pancreas

is the long, tapering part extending to the (L) behind the stomach

Tail of the Pancreas

is its pointed (L) end of pancreas

Pancreatic Duct/Duct of Wirsung

is a hollow tube that extends from the tail, through the body and head to join the Common Bile duct which carries the pancreatic fluid to the duodenum.

Pancreatic fluid/juice

Pancreas is made up of many minute glands that manufacture and secrete digestive enzyme called ______________ which is collected by these tiny ducts.

Islets of Langerhans/Islands of Langerhans

are small clumps of cells scattered throughout the Pancreas

Insulin

They have no duct, but their secretions ______ is absorbed by the capillary blood vessels and necessary for the utilization of Glucose by the cells.

Diabetes

Absence of Insulin causes __________-

LIVER

is the largest solid organ in the body and may weigh 3 pounds. It occupies the upper (R) abdomen but extends to the (L) side of the body. When viewed from the front, it is roughly triangular in shape

Hepatic cells

are the one responsible in secreting bile into the bile ducts to approximately 1-3 pints per day.

Bile

has no enzymatic action but emulsifies fats, breaking up large fat particles into smaller ones, which creates a larger surface area for more efficient lipase activity.

GALL BLADDER

is a pear-shaped hollow organ which lies in an impression below the liver that serves as a reservoir for bile. It is located in the RUQ and opposite the ninth costal cartilage but may also be lower.

Fundus, Body, Neck

Parts of the Gall Bladder:

Cystic Duct (Ductus Cysticus)

is a hollow tube that passes from the gall bladder to join the hepatic duct.

Common Bile Duct (Ductus Choledochus)

is formed by the union of the (R) Hepatic duct or the Ductus Hepaticus Dexter and (L) Hepatic duct or Ductus Hepaticus Cummunis and cystic duct.

Sphincter of Oddi

It passes down behind the descending duodenum and opens into the “Ampulla of Vater/Hepato-Pancreatic ampulla” which has a sphincter called ___________

Cholecystokinin

is another hormone with its source from the duodenum that increases output of enzymic-rich pancreatic juice, stimulates the Gall Bladder to expel stored bile and it relaxes the sphincter of oddi to allow bile and pancreatic juice to enter the duodenum.

DIGESTION

is the breaking up or the mechanical and chemical breakdown of food to simple molecules that can be absorbed and used by body cells.

ABSORPTION

is the passage of digested products through lining membrane of the bowel into the blood or lymph capillaries.