Digestion

You have learned that your cells use carbohydrates, proteins, fats, vitamins, minerals and water to make your body. And that is what you eat, in all about 65,000 pounds (29,510 kg) of food during your lifetime!

Your digestive system is an incredible food processor, a tube that churns and turns food into substances that your cells can use. You decide what to put into your mouth and whether or not to chew and swallow it, but after that the tube takes over. Open at both ends, the tube that makes up the digestive tract is between 8-9m long. A meal passes through the digestive tract in 24-30 hours. The small intestine, on its own measures 6.5m long. The digestive

tract is also called the gastrointestinal tract. is the ___________________________ and ___________________________ process of

breaking down food to release ___________________________ in a form the body can use.

Digestive tract (alimentary canal) - 8 coiled meters long; mostly found in the rib cage.

MASTICATION (CHEWING)saliva, mucus, glands under the tongue.

___________________________, a carb. enzyme saliva is a mixture of ___________________________, mucus, ___________________________,

and ___________________________. people produce 1.5 L of saliva each day.

FUNCTIONS OF SALIVA1. adds ___________________________ and ___________________________ to food2. ___________________________ food3. cleans ___________________________ and ___________________________

4. makes slightly basic liquid, buffer

Pharynx:- dual purpose ___________________________- receives both ___________________________

from the ___________________________ and ___________________________ from the ___________________________

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- everytime you swallow, the ___________________________, a flap-like structure that ensures food will travel down the digestive tract

The Esophagus- where food goes once _________________________- muscular tube

connecting the mouth to the

_________________________- walls of the esophagus are made up of smooth muscle tissue that contact

and relax creating _________________________movements that force food into the stomach (this muscular action is called _________________________)

STOMACH sweet

potato shape

holds___________________________l of food when full

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___________________________sets of ___________________________ that churn food around.

GASTRIC JUICES1. ___________________________ - pH of 2 breaks down

protein & bacteria2. ___________________________ - pepsin (protein), rennin (protein), gastric lipase (fat). Amylase (starches) is destroyed by acid.3. ___________________________- protects the lining of

stomach.

MACRONUTRIENTS BREAKDOWN1. carbs - ___________________________hours2. protein - ___________________________hours

3. fats - ___________________________hoursCHYME - thick fluid made of ___________________________.PYLORIC SPHINCTER - a muscle that control’s the movement of food from the stomach to the small intestine.

- food released a little at a time.

Small Intestine- ___________________________meters long, ___________________________cm diameter- performs___________________________.- 3 segments, ___________________________, jejunum, ileum-- ___________________________ – digestive juices enter here from the bile duct and

pancreas.

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JEJUNUM- many folds that secrete ___________________________from lining that breakdown ___________________________and ___________________________ so they can pass through the villi. Its covered with microvilli that absorb a specific ___________________________, or amino acid.- ___________________________ of nutrients in order of being broken down. 1. carbs 2.protein 3. fat

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- these nutrients are carried 1st by the lymphatic system and then the circulatory system.

ILEUM- diameter 5 cm, 1.5 m long- attached to the large___________________________, little villi here, few enzymes.- peristalysis to move undigested food to large intestine.- main function is ___________________________.LIVER & PANCREAS

produces ___________________________, greenish liquid used to mix with fat so it can be ___________________________ and ___________________________

bile stored in the gall ___________________________, bile duct.PANCREAS - pancreatic juice,enzyme – rich fluid that helps breakdown all 3 nutrients.

- releases Na2CO3 to neutralize acid fluid from stomach.

LARGE INTESTINE- 1.5 m long- diameter___________________________of small intestine- ___________________________plays a role in digestion in horses.

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3 Main Functions of the Large Intestine1. Bacterial Action - bacteria live in the

___________________________ and breakdown any carbs not broken down earlier.

2. Water Recovery - water ___________________________into body and salts.

3. Collection of Waste - elimination of waste.- feces is living, dead

bacteria, cellulose, and water.RECTUM & ANUS

Weak sphincter muscles push feces to rectum where it is stored. 2 other sphincter muscles inside and out of the anus push it out.

CHARACTERISTICS OF HEALTHY FECES

NO SMELL BEIGE COLOR ALL ONE PIECE FLOATS NO STRAINING WHEN

PUSHING OUT ALL ONE COLOR GO 2 OR MORE TIMES A

DAY

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