Digestion -Quiz 3/1

2 types of digestion:

Mechanical (mastication) Chemical (enzymes)

3 parts of small intestine

-Duodenum -Jejumum -Ileum

Stomach -What does the stomach expand to during a meal? -How much gastric juice is secreted each day? -What does Gastric juice contain?

-During a meal, the stomach gradually fills to capacity of 1 liter, from an empty capacity of 50-100 milliliters. -At a price of discomfort, the stomach can distend to hold 2 liters or more. -The stomach secretes about 2 liters of gastric juices per day -Gastric juice contains hydrochloric acid, pepsinogen, and mucus.

Enzyme of Digestive System Pepsin (_________ --> ___________ and __________)

(proteins --> peptones and proteoses)

Bile (not an enzyme)

emulsification of lipids

Enzyme of Digestive System Salivary amylase (_________ --> ___________)

(starch --> sugar)

Stomach to Duodenum -How long does the stomach empty over?

-Acidic Chyme is pushed from the lower part of the stomach through the pyloric sphincter into the duodenum (first part of small intestines) -The stomach empties over a 1 to 2 hour period

What are the accessory organs?

-Liver -Pancreas -Gall Bladder

What is the purpose of chewing?

the purpose is to increase the surface area of food. (speeds up digestion)

peristalsis

the wave action of muscle that moves food through the digestive system

3 stages of digestion

1.Digestion 2. Absorption of nutrients into the bloodstream 3. Elimination of indigestible nutrients (egestion)

Stomach pepsin

is an enzyme that controls the hydrolysis of proteins into peptides

Organs of the Digestive System

-Mouth -Salivary Glands -Esophagus -Stomach -Small intestine -Liver -Pancreas -Gall Bladder -Intestinal Glands -Large intestine -Rectum -Anus

esophagus

is a muscular tube whose muscular contractions (peristalsis) propel food to the stomach

Chyme

is liquified food, mix of acid and food in the stomach which leaves the stomach and enters the small intestine.

Small Intestine

is the major site for digestion and absorption of nutrients

bolus

it is the chemical breakdown mixture of food and saliva that is made into a mass of food

Enzyme of Digestive System Intestinal Juice -Peptidase(_________ --> ___________) -Maltase(__________ --> _____________)

-Peptidase (peptides --> amino acids) -Maltase (disaccharides --> monosaccharides)

What happens after the food is mixed with Saliva?

the food is then pushed into the pharynx by the tongue which triggers involuntary swallowing

Enzyme of Digestive System Pancreatic Juice -Amylase(_________ --> ___________) -Trypsin (_________ and __________--> ___________ ) -Lipase(_________ --> ___________ and __________)

-Amylase (polysaccharides --> disaccharides) -Trypsin (peptones and proteoses --> peptides) -Lipase(Lipids --> Glycerol and 3 fatty acids)

Duodenum -Chyme is pushed from the ___________ to the _______________ -acid chyme stimulates the ____________ -The pancreas secretes _____________________ -The liver produces ____________ which is stored in the _____________________ before entering the ________________ into the _____________. -Bile emulsifies ____________ and breaks ________ into small pieces

-Chyme is pushed out of the stomach into the small intestines. The acid chyme stimulates the liver. -The pancreas secretes digestive enzymes and stomach acid-neutralizing sodium bicarbonate (2 pH → 8 pH) --Enzymes - Lipase, Amylase, Trypsin -The liver produces bile, which is stored in the gall bladder before entering the bile duct into the duodenum -Bile emulsifies fats and breaks fats into little pieces

Protein DigestionStep by Step -proteins begin to be digested by _________________ in the ________________ while being liquified by the acid _____________ -The __________ is pushed in to the _____________ which triggers the release of ______________ from the _______________ -___________ is one of the enzymes in pancreatic juice which continues the breakdown of ______________ into ____________ -intestinal juice includes _________________ which breaks _______________ bonds into ___________________ -amino acids are ________________ into the bloodstream and carries to the cells for use

-Proteins begin to be digested by Pepsin in the stomach while being liquified by the acid HCL. -The chyme is pushed into your small intestines (duodenum) which triggers the release of pancreatic juice from the pancreas -Trypsin is one of the enzymes in pancreatic juice which continues the breakdown of proteins into peptides -Finally the intestinal glands release intestinal juice which includes peptidase which breaks peptide bonds into amino acids. (jejunum) -Those amino acids are absorbed into the bloodstream and carries to the cells for use. (ileum)

Enzymes and Where they are used: -Salivary amylase -Pepsin -Bile -Pancreatic Juice --Amylase --Trypsin --Lipase -Intestinal Juice --Peptidase --Maltase

-Salivary amylase (starch → sugar) MOUTH -Pepsin (proteins → Polypeptides) STOMACH -Bile(emulsification of lipids) DUODENUM -Pancreatic Juice DUODENUM --Amylase (polysaccharides → disaccharides) --Trypsin (peptones and proteoses → peptides) --Lipase (lipids → glycerol and fatty acids) -Intestinal Juice JEJUNUM and ILEUM --Peptidase (peptides → amino acids) --Maltase (disaccharide → monosaccharides)

Carbohydrates Digestionstep by step -The _________ is pushed into your ______________ (duodenum) which triggers the release of_______________ from the _____________ -Amylase is one of the enzymes in the _____________________ which breaks down polysaccharides into __________________ -Finally the intestinal glands release___________________ which includes the enzyme _____________ (jejunum) -Maltase breaks down the _______________ into monosaccharides which are absorbed by the bloodstream -Monosaccharides are _______________ into the bloodstream and carried to the cells for use.

-The chyme is pushed into your small intestines (duodenum) which triggers the release of pancreatic juice from the pancreas -Amylase is one of the enzymes in the pancreatic juice which breaks down polysaccharides into disaccharides -Finally the intestinal glands release intestinal juice which includes the enzyme maltase. (jejunum) -Maltase breaks down the disaccharides into monosaccharides which are absorbed by the bloodstream -Monosaccharides are absorbed into bloodstream and carried to the cells for use.

Digestion of lipids -_____________ is pushed into the small intestines which triggers the release of ___________________ from the pancreas and ___________ from the gall bladder -Bile emulsifies the lipids to ___________________ -Lipase is found in _______________ which hydrolyzes lipids into a _________________ and _____________________ -products are absorbed by ___________________ into the ____________ and carries to the cells for use

-The chyme is pushed into your small intestines (duodenum) which triggers the release of pancreatic juice from the pancreas and bile from your gall bladder. -Bile emulsifies (chews) the lipids to increase surface area -Lipase that is found in pancreatic juice which hydrolyzes (break down) lipids into a glycerol and 3 fatty acids -The products are absorbed by the small intestines into the blood and carries to the cells for use. (jejunum and illeum)

The Large Intestines -made up of _____________________________ -_______________ food us pushed from the _________________ into the large intestine -NO _______________ takes place here -material in the large intestine is mostly __________________ and ____________ -__________________ and ___________ are absorbed -bacteria in the large intestine produce _____________ that are _____________

-The large intestine is made up of the cecum, appendix, colon, and rectum. -Digested food is pushed from the small intestines into the large intestine. -No digestion takes place in the large intestines. -Material in the large intestine is mostly indigestible residue and liquid -Water, and salts are absorbed, the remaining contents from feces (mostly cellulose, bacteria, bilirubin) -Bacteria in the large intestine, such as E.coli, produce vitamins (including vitamin K) that are absorbed.

The Liver andGall Bladder -Liver make ________ which is stored in the ____________________ -Gall bladder sends bile to ________________ with the _____________________ from the __________ -Bile contains __________ which emulsify _________ making them susceptible to ______________________ -The liver stores excess ___________________ in the form of ________________

-The liver makes Bile and stores it in the gall bladder. -The Gall bladder sends bile to the small intestines with the acidic chyme from the stomach. Bile contains bile salts, which emulsify fats, making them susceptible to enzymatic breakdown. -The liver also stores excess glucose in the form of glycogen.

Villi and Microvilli -The small intestine is lined with ______________________ -purpose of villi and microvilli is to _______________________ in the _________________________ and increase the ___________ at which nutrients are ________________ -Each villus has a _____________________ supplied by _________________ -_______________ nutrients pass through the ____________ into the capillary by ___________ transport

-The small intestine is lined with villi and microvilli -The purpose of villi and microvilli are to increase surface area in the small intestines and increase the speed at which nutrients are absorbed. --The small intestines a 6 meter long tube has a surface area of 300 square meters or the surface area of 500-600m long tube. -Each villus has a capillary network supplied by a small arteriole. Absorbed nutrients pass through the microvilli into the capillary (blood stream), usually by passive transport.

The Mouth Chemical Breakdown

Chemical breakdown of starch also begins in the mouth. Starch is converted into glucose by salivary amylase(secreted by the salivary glands)

Digestion

breakdown of food into particles/molecules small enough to pass into the bloodstream

Acronym to remember digestive tract

MESSI LIRA

The Mouth Mechanical Breakdown

Mechanical breakdown of nutrients begins in the mouth by chewing (Mastication).