Digestive SystemDigestive System

Mrs. MorganMrs. Morgan

BiologyBiology

Digestive SystemDigestive System

MouthMouth

Where digestion beginsWhere digestion begins The lips, cheeks, and The lips, cheeks, and

tongue are all involved in tongue are all involved in the processthe process

The teeth break down food The teeth break down food physicallyphysically

The 3 sets of salivary The 3 sets of salivary glandsglands– Lubricate foodLubricate food– Break up starchBreak up starch– Dissolve some foodsDissolve some foods– Attack dangerous Attack dangerous

microorganismsmicroorganisms

Source: www.pittsburghfacialandorgalsurgery.com

PharynxPharynx

Also known as the Also known as the throatthroat

Area between the Area between the mouth and mouth and esophagusesophagus

Passage for both Passage for both food and oxygenfood and oxygen

A bolus is a ball of A bolus is a ball of foodfood

Source: www.taxotere.com

EsophagusEsophagus A tube that is A tube that is

approximately 23-25cm approximately 23-25cm long that connects the long that connects the mouth and stomachmouth and stomach

The epiglottis is a flap The epiglottis is a flap of cartilage that covers of cartilage that covers the windpipe when the windpipe when swallowingswallowing

Peristalsis is rhythmic Peristalsis is rhythmic muscular contractions muscular contractions that moves food from that moves food from mouth to the stomachmouth to the stomach

Source: www.uic.edu

StomachStomach A “J” shaped organA “J” shaped organ Used for storage and it Used for storage and it

regulates the flow of regulates the flow of food into the small food into the small intestineintestine

Holds 1 liter of foodHolds 1 liter of food Digestion in the stomach Digestion in the stomach

take between 2-5 hourstake between 2-5 hours Contains pepsin (digests Contains pepsin (digests

protein) and protein) and hydrochloric acid (helps hydrochloric acid (helps break down food)break down food)

Source: www.gispecialists.net

PancreasPancreas

Approximately Approximately 12.5cm long x 2.5cm 12.5cm long x 2.5cm thickthick

Main role is to Main role is to secrete 3 enzymes secrete 3 enzymes into the small into the small intestineintestine

These enzymes These enzymes break down break down carbohydrates, carbohydrates, proteins, and fatsproteins, and fats

Source: undagroundmilli.wordpress.com

GallbladderGallbladder Approximately 7-10cm Approximately 7-10cm

longlong Main function is to Main function is to

store bile and then store bile and then injects it into the small injects it into the small intestineintestine

Bile breaks down fat Bile breaks down fat molecules into small molecules into small fat moleculesfat molecules

Gallstones form when Gallstones form when there is too much there is too much cholesterol in the bile. cholesterol in the bile. They can cause pain They can cause pain when they block ducts.when they block ducts.

Source: www.singleincisionlapchole.com

LiverLiver It is the largest organ in the It is the largest organ in the

body…weighs about 3lbsbody…weighs about 3lbs The liver's main job is to filter The liver's main job is to filter

the blood coming from the the blood coming from the digestive tract, before passing digestive tract, before passing it to the rest of the body. The it to the rest of the body. The liver also detoxifies chemicals liver also detoxifies chemicals and metabolizes drugs. As it and metabolizes drugs. As it does so, the liver secretes bile does so, the liver secretes bile that ends up back in the that ends up back in the intestines. The liver also makes intestines. The liver also makes proteins important for blood proteins important for blood clotting and other functions. clotting and other functions. Hepatitis: Inflammation of the liver, usually caused by viruses like hepatitis A, B, and C. Hepatitis can have non-infectious causes too, including heavy drinking, drugs, allergic reactions, or obesity.

Source: webmd.com

Small IntestineSmall Intestine

6.35m long x 2.5cm 6.35m long x 2.5cm diameterdiameter

Most of digestion Most of digestion and absorption of and absorption of nutrients occursnutrients occurs

It can take 3-6 hours It can take 3-6 hours for a meal to pass for a meal to pass from one end to the from one end to the other…depends on other…depends on what you eatwhat you eat

Source: www.health.com

Large IntestineLarge Intestine

Also known as the Also known as the coloncolon

1.5m long x 6.5cm 1.5m long x 6.5cm diameterdiameter

Main function is the Main function is the absorption of waterabsorption of water

Removes water Removes water from undigested from undigested foodfoodfecesfeces

Source: www.nlm.nih.gov

AnusAnus The endThe end It has 2 sets of sphincters It has 2 sets of sphincters

(ringlike muscle that (ringlike muscle that normally maintains normally maintains constriction of a body constriction of a body passage or orifice and that passage or orifice and that relaxes as required by relaxes as required by normal physiological normal physiological functioning)functioning)

Diarrhea happens when too Diarrhea happens when too little water is absorbedlittle water is absorbed

Constipation is slow Constipation is slow movement of fecal matter; movement of fecal matter; too much water is absorbedtoo much water is absorbed Source: digestive.niddk.nih.gov

Digestive System FactsDigestive System Facts Organs that make up the digestive tract:

– Mouth – Esophagus – Stomach – Small Intestine – Large Intestine (colon) – Rectum – Anus

Organs that help with digestion but are not part of the digestive tract: – Tongue – Glands in the mouth that make saliva – Pancreas – Liver

– Gallbladder

Digestive System FactsDigestive System Facts An adult esophagus (also called gullet) ranges from 10 to 14

inches in length, and 1 inch in diameter. We make 1 to 3 pints of saliva a day. Muscles contract in waves to move the food down the

esophagus. This means that food would get to a person's stomach, even if they were standing on their head.

It takes your mouth, esophagus, stomach, small intestine, large intestine, gallbladder, pancreas and liver just to digest a glass of milk.

An adults stomach can hold approximately 1.5 liters of material. The stomach's wall is lined with three layers of powerful

muscles. The average male will eat about 50 tons of food during his

lifetime in order to sustain a weight of 150 pounds.

Digestive System FactsDigestive System Facts In the mouth, food is either cooled or warmed to a more

suitable temperature. The liver performs more than 500 functions. The small intestine (pronounced in-test-in) is a long tube

about 1 and a half to 2 inches around, and about 22 feet long. The large intestine is fatter than the small intestine at about

3 to 4 inches around, but shorter than the small intestine at about 5 feet long.

A full grown horse?? Their coiled up intestines are 89 feet long.

The digestive tract is like a long tube, approximately 30 feet long in total, through the middle of the body. It starts at the mouth, where food and drink enter the body, and finishes at the anus, where leftover food and wastes leave the body.

Digestive System FactsDigestive System Facts Within the colon, a typical person harbors more than 400

distinct species of bacteria. On average, the stomach produces 2 liters of Hydrochloric

Acid (HCl) daily. After you eat, it takes usually between 24 and 72 hours in

healthy adults for the complete process of digestion to occur.

All the different varieties of food we eat are broken down by our digestive system and transported to every part of our body by our circulatory system.

Food stays in your stomach for 2 to 3 hours.

Source: www.nexiumresearch.com

Digestive SystemDigestive System

QuizQuiz1. The pharynx is also known as the1. The pharynx is also known as the

a. epiglottisa. epiglottis b. throatb. throat c. tonsilsc. tonsils

2. What conducts food from the mouth to the stomach?2. What conducts food from the mouth to the stomach?

a. esophagusa. esophagus b. epiglottisb. epiglottis c. pharynxc. pharynx

3.3. What foods are broken down in the esophagus?What foods are broken down in the esophagus?

1. fats1. fats 2. proteins2. proteins 3. carbohydrates3. carbohydrates

a. none of the abovea. none of the above b. all of the aboveb. all of the above c. 1,2,3c. 1,2,3

4.4. What chemical does the liver produce that breaks down What chemical does the liver produce that breaks down fat droplets?fat droplets?

a. pepsina. pepsin b. acidb. acid c. bile c. bile

5.5. What is the largest organ in the body?What is the largest organ in the body?

a. esophagusa. esophagus b. mouthb. mouth c. liverc. liver

d. stomachd. stomach e. pancrease. pancreas f. rectumf. rectum

g. small intestineg. small intestine h. large intestineh. large intestine

6.6. TRUE/FALSE – The pancreas secretes digestive TRUE/FALSE – The pancreas secretes digestive enzymes into the small intestine. enzymes into the small intestine.

7.7. The pancreas makes 3 different enzymes that…The pancreas makes 3 different enzymes that…

a. help break down fatsa. help break down fats

b. help break down carbohydratesb. help break down carbohydrates

c. help break down proteinsc. help break down proteins

d. all of the aboved. all of the above

e. none of the abovee. none of the above

8.8. ______ is the small bag-like organ located under ______ is the small bag-like organ located under the liver that stores bile.the liver that stores bile.

9.9. TRUE/FALSE – Most of the chemical digestion of TRUE/FALSE – Most of the chemical digestion of food takes place in the small intestine.food takes place in the small intestine.

10.10. What is the main job of the large intestine?What is the main job of the large intestine?

11.11. What digestive organ(s) move food through by What digestive organ(s) move food through by peristalsis?peristalsis?

1. esophagus1. esophagus 2. stomach2. stomach 3. liver3. liver

4. pancreas4. pancreas 5. mouth5. mouth 6. large intestine6. large intestine

a. 1 & 6a. 1 & 6 b. Only 1b. Only 1 c. 3 & 4c. 3 & 4

d. 2 & 6d. 2 & 6 e. 3 & 5e. 3 & 5 f. all of themf. all of them