Download Digestive System

Digestive System
Leshel Ponce, Elizabeth
Cobian, Sasha Padilla
Period 3
What is the Digestive System?
● The Digestive system is
a group of organs that
work together to convert
food into energy and
basic nutrients to feed
the entire body.
Macromolecules
● travel through digestive tract as a
carbohydrate, like starch and sugar
but cannot be digested
● provide nutrition
-Carbohydrates
-Protein
-Nucleic Acids
-Lipids
Macromolecules
●
Carbohydrates- provide materials to build cell membranes, and build quick energy for
cells
Ex: Monosaccharides, disaccharides, polysaccharides
●
Lipids-energy source
Ex: Fats, oils
●
Nucleic Acids- growth and development of organism
Ex: DNA and RNA
●
Protein- build and repair muscles and cell membranes, fight infections
Ex: antibodies, most enzymes and hormones
Alimentary Canal
● passage along which food passes
through the body
○ mouth
○ pharynx
○ esophagus
○ stomach
○ small intestine
○ large intestine
○ rectum
Accessory Organs
An organ that helps with digestion,
but is not part of the digestive tract
teeth
tongue
salivary glands
liver
gallbladder
pancreas
Mouth
Function:
receives food, breaks solid particles
into smaller particles using the
teeth
then mixes them together with help
of the tongue and saliva
● Macromolecules:
○
carbohydrates, lipids
Salivary Glands
Parotid Gland
Watery serous fluid
Sublingual Gland
thick mucous fluid
Submandibular Gland
mixed serous and mucous fluid
Enzymes
Mouth
Salivary Amylase - Breaks apart
starch into oligosaccharides
Lingual Lipase - Breaks down fats in
mouth
Pharynx
Location:
throat, connects nasal and oral cavity to
the esophagus
Function:
serves as a passageway to the
esophagus
Esophagus
Location:
runs behind the trachea, heart, and in front of
the spine
Function:
passageway from pharynx to the stomach
mucus moistens and lubricates inner lining
making it easy for food to pass through
Peristalsis
wave like muscle contractions that help move
Stomach
Locations:
hangs inferior to the diaphragm in the upper
left portion of the abdominal cavity
● Function:
receives food from the esophagus
mixed it with gastric juices
initiates digestion of proteins
carries on limited absorption
moves food into small intestine
Gastrin
● come from G cells located in gastric pits
● stimulates gastric glands to secrete
enzymes and acid
● help to secrete pepsinogen and
hydrochloric acid
● secretion caused by food arriving in
stomach
● affects pancreas, liver, and intestines
Motilin
● produced from endocrine cells of
duodenal mucosa
● increases migrating myoelectric
complex component of
gastrointestinal motility
● stimulates pepsin production
● affects stomach and small intestine
Ghrelin
● produced in stomach and upper
intestine
● tells the brain that the body
needs to be fed
Enzymes
Stomach
Pepsin - Breaks proteins into
polypeptides
Mucus - Protects stomach from
pepsin and hydrochloric acid
Lipases - Breaks down fats
Liver
Location:
upper right quadrant of the abdominal
cavity, inferior to the diaphragm
Function:
produces bile that emulsifies fat
Pancreas
Location:
extends horizontally across the
posterior abdominal wall with its
head on the
Function:
Produces and secretes pancreatic
juice containing digestive enzymes
and bicarbonate ions into the small
intestine
Secretin
comes from hydrochloric acid
passing from stomach into
duodenum
signals secretion of sodium
bicarbonate in pancreas and
liver
regulate duodenum activity
affects pancreas and liver
Gallbladder
Location:
pear shaped sac in a depression on
the inferior surface of the liver
Function:
stores bile and introduces it to the
small intestine
Cholecystokinin
● come from mucosal epithelial cells in
small intestine
● stimulate release of digestive
enzymes in pancreas and empties
bile in gallbladder
● improves digestion
● affects gallbladder, small intestine,
and pancreas
Small Intestine
● Location:
tubular organ that loops and coils to fill
most of the abdominal cavity
● Function:
receives secretion from the pancreas and
liver
completes digestion of nutrients
absorbs the products of digestion
transports the remaining residues to the
large intestine
● Macromolecules:
Gastric Inhibitory Peptide
● comes from mucosal epithelial cells
in small intestine
● increases insulin secretion in
response to infusions of glucose
● affects glucose absorption and
small intestine
Enzymes
Small Intestine
Lipases - Breaks down fat
Amylases - Breaks down large carbohydrate
chains
Proteases - Breaks down protein
Bile Salts - Breaks down fat
Maltase - Breaks maltose into two glucose
Enzymes
Small Intestines Continue…
Nucleosidases - Breaks down nucleotides into base,
sugar, and phosphate
Sucrase - Breaks sucrose into glucose and fructose
Dipeptides - Breaks down peptides into amino acids
Carbohydrase - Breaks starch into glucose
Large Intestine
Location:
tubular organ that begins in the lower right
side of the abdominal cavity and
descends into the pelvis
Function:
absorbs ingested water and electrolytes
remaining in the alimentary system
reabsorbs and recycles water and
remnants of digestive secretion to form
feces
Rectum
Location:
next to the sacrum, ending at the end
of the coccyx
Function:
serves as storage and it regulates
the elimination of feces
Anus
Location:
tip of the coccyx
Function:
contains muscles under voluntary
control to eliminate feces
Digestion Structures
Mouth (Mechanical + Chemical)
Pharynx (Mechanical)
Esophagus (Mechanical)
Stomach (Mechanical)
Small Intestine (Chemical)
Large Intestine (Chemical)
Enzymes
Most Important
Bibliography
“Digestive System.” Inner Body. N.p., n.d. Web. 1 Feb. 2016.
“Extraordinary Lives Start With a Great Catholic Education.” Dufferin-Peel Catholic District School Board. N.p., n.d. Web. 1
Feb. 2016.
“’How to Help Prevent Occasional Bouts of Bloating, Gas, and Indigestion with Two Very Specialized Formulas*.’” Dr.
Mercola. N.p., n.d. Web. 1 Feb. 2016.
Kitses. N.p., n.d. Web. 1 Feb. 2016. <http://kitses.com/animation/swfs/digestion.swf>.
“Mechanical and Chemical Digestion.” The Smart Living Network. N.p., 10 Apr. 2010. Web. 1 Feb. 2016.
“Textbook Innovation.” Boundless. N.p., n.d. Web. 1 Feb. 2016.