Transcript Digestive System

DIGESTIVE SYSTEM
By Wesley Glanton & Rashad Walker
HOW IT WORKS
• In the human digestive system, the process of digestion has many stages, the first of
which starts in the mouth (oral cavity). Digestion involves the breakdown of food into
smaller and smaller components which can be absorbed and assimilated into the body.
The secretion of saliva helps to produce a bolus which can be swallowed in the
esophagus to pass down into the stomach.
• Saliva starts to act on food in the mouth. Digestion is helped by the mastication of food
by the teeth and also by the muscular contractions. Gastric juice in the stomach is
essential for the continuation of digestion as is the production of mucus in the stomach.
• The rhythmic contraction of muscles that begins in the esophagus and continues along
the wall of the stomach and the rest of the gastrointestinal tract. This initially results in the
production of chyme which when fully broken down in the small intestine is absorbed
into the blood. Most of the digestion of food takes place in the small intestine. Water and
some minerals are reabsorbed back into the blood, in the colon of the large intestine.
The waste products of digestion are defecated from the anus via the rectum.
WHAT IT DOES
• The six primary processes of the
digestive system include:
• 1.Ingestion of food
• 2.Secretion of fluids and digestive
enzymes
• 3.Mixing and movement of food
and wastes through the body
• 4.Digestion of food into smaller
pieces
• 5.Absorption of nutrients
• 6.Excretion of wastes
ORGANS IN THE SYSTEM
• Mouth
• Pharynx
• Esophagus
• Stomach
• Small intestine
• Liver
• Gallbladder
• Pancreas
• Large intestine
WHAT IT USES
• Mouth -Food begins its journey through the digestive
system in the mouth, also known as the oral cavity.
Inside the mouth are many accessory organs that aid
in the digestion of food—the tongue, teeth, and
salivary glands. Teeth chop food into small pieces,
which are moistened by saliva before the tongue and
other muscles push the food into the pharynx.
• The pharynx is responsible for the passing of masses of
chewed food from the mouth to the esophagus.
• The esophagus carries swallowed masses of chewed
food along its length, the sphincter at the end close
and traps food in the stomach.
WHAT IT USES CONTINUED…
• Stomach -This major organ acts as a storage tank
for food so that the body has time to digest large
meals properly. The stomach also contains
hydrochloric acid and digestive enzymes that
continue the digestion of food that began in the
mouth.
• Small intestine- The entire small intestine is coiled
like a hose and the inside surface is full of many
ridges and folds. These folds are used to maximize
the digestion of food and absorption of nutrients.
• Liver- the main function of the liver in digestion is
the production of bile and its secretion into the
small intestine.
WHAT IT USES CONTINUED…
• The gallbladder is used to store and recycle
excess bile from the small intestine so that it can
be reused for the digestion of subsequent
meals.
• Pancreas- secretes digestive enzymes into the
small intestine to complete the chemical
digestion of foods.
• The large intestine absorbs water and contains
many symbiotic bacteria that aid in the
breaking down of wastes to extract some small
amounts of nutrients. Feces in the large intestine
exit the body through the anal canal.
WHAT IT DIGESTS
• Carbohydrates are the sugars, starches, and fiber
found in many foods. Carbohydrates are called simple
or complex, depending on their chemical structure.
Simple carbohydrates include sugars found naturally in
foods such as fruits, vegetables, milk, and milk
products, as well as sugars added during food
processing. Complex carbohydrates are starches and
fiber found in whole-grain breads and cereals, starchy
vegetables, and legumes.
• Protein. Foods such as meat, eggs, and beans consist
of large molecules of protein that the body digests into
smaller molecules called amino acids. The body
absorbs amino acids through the small intestine into the
blood, which then carries them throughout the body.
WHAT IT DIGESTS CONTINUES…
• Fats. Fat molecules are a rich source of energy
for the body and help the body absorb vitamins.
Oils, such as corn, canola, olive, safflower,
soybean, and sunflower, are examples of
healthy fats. Butter, shortening, and snack foods
are examples of less healthy fats.
• Vitamins. Scientists classify vitamins by the fluid in
which they dissolve. Water-soluble vitamins
include all the B vitamins and vitamin C. Fatsoluble vitamins include vitamins A, D, E, and K.
Each vitamin has a different role in the body’s
growth and health.
BAD OUTCOMES
• Poor digestion leaves the body and the
immune system in the same predicament
that poor nutrition does – a lack of
nutritional factors that support immune
functioning and the function of the entire
body. This is because a poor functioning
digestive system has lost some of the ability
to turn what’s consumed into a form the
body can use.
• An inadequate digestive system will “steal”
enzymes from the immune system to
operate therefore weakening immune
function. Poor digestive capability increases
the body’s toxic load.
GOOD OUTCOMES
• Regularity. Let's start with the one you
knew already. Fiber, particularly
insoluble fiber, can help people prevent
constipation. It bulks up stools and
keeps food moving through the
digestive tract.
• Healthy bacteria. You might have
heard of probiotics -- healthy bacteria
that live in your intestines. Some types of
soluble fiber are considered a prebiotic
-- a fuel that feeds these healthy
bacteria and increases their numbers.
What do these bacteria do? They boost
digestive health.