digestive system notes

Digestive System Notes

Mouth

Esophagus

Stomach

Small Intestine

Large Intestine

System have BFS…. IC

Interconnectedness Changes

The “BFS”

• Behavior = Role (role of each part)

• Function = Purpose (purpose of the whole system)

• Structure = Parts

BF Behavior vs. FunctionBehavior is specificFunction is general

System have BFS…. IC

• Interconnection – there are links between parts

• Changes – If a part fails to perform, it will affect the whole system

How do the COMPONENTS of a

System INTERCONNECT?

STRUCTURE OF SYSTEM

The Digestive System Use the words below to label the parts of the digestive system. Liver large intestine appendix anus oesophagus rectum small intestine stomach mouth

The Digestive System Use the words below to label the parts of the digestive system. Liver large intestine appendix anus oesophagus rectum small intestine stomach mouth

TheDigestiveSystem

Mouth / Teeth

Esophagus

Liver

Stomach

Small intestine

Large intestine

Rectum

Anus

Appendix

OBSERVING DIGESTIVE ORGANS1. The esophagus

a. How would you describe the esophagus?

b. How is it designed to perform its behavior?

2. External and internal structure of the stomach. a. How would you describe the external appearance of the stomach?

b. What is the action (behavior) of the stomach?

c. How is the stomach designed to perform its behavior?

3. External and internal structure of the small and large

intestines a. Describe the appearance of the small and large intestines.

b. What are the main actions (behavior) of the small and large intestines?

c. How is the small intestine designed to perform its behavior?

INGESTION

FUNCTION/ PURPOSE OF SYSTEM

Digestionbreakdown of food into

molecular components small enough to cross the plasma membrane

DigestionDefinition• Digestion is the breaking down of food into

smaller and simpler substances

– Mechanical digestion and Chemical digestion do this in different ways

ABSORBED ELIMINATED

DigestionDefinition• MECHANICAL (physical) digestion

– breaking down of food into smaller pieces– involves: chewing, grinding, churning

• CHEMICAL digestion– Breaking down of food into simpler substances

(building blocks)– involves: enzymes , bile, HCL acid

• ABSORPTION– Broken down food gets from digestive tract into

the body (blood)

Mechanical DigestionSame volume of food

Small total surface areaLarger total surface area

A larger surface area speeds up digestion

saliva

saliva

saliva

Smaller pieces allow for more areas of contact for enzymes and digestive juices to act on speeding up digestion

DigestionDefinition• Digestion is the breaking down of food into

smaller and simpler substances

• Mechanical digestion and Chemical digestion do this in different ways

ABSORBED ELIMINATED

Chemical Digestion is the breaking down of large complicated molecules into simpler ones by the use of enzymes

http://web.ukonline.co.uk/webwise/spinneret/other/anenz.htm

ENZYME

Orange- food Red and yellow- products

(glucose)

Smaller pieces allow for more areas of contact for enzymes and digestive juices to act on speeding up chemical digestion

MECHANICAL

CHEMICAL

Absorption

passage of molecules into body's interior &passage throughout the body

LARGE INTESTINES

ELIMINATION OF WASTE

REABSORBS WATER & SALTS

STRUCTURE OF SYSTEM

TheDigestiveSystem

Mouth / Teeth

Esophagus

Liver

Stomach

Small intestine

Large intestine

Rectum

Anus

Appendix

Cone-shaped tongue papillae, seen here in a colored scanning electron micrograph, contain nerve endings that receive and transmit touch sensations to the brain.

As we begin chewing, the tongue shapes food in a ball-shaped bolus for swallowing.

http://science.nationalgeographic.com/science/photos/digestive-system/?source=A-to-Z#/tongue-papillar_1251_600x450.jpg

Tongue PapillaePhotograph by SPL/Photo Researchers, Inc.

Inside the mouth, shown magnified here, teeth, tongue, and saliva work together to physically and chemically break down food.

Humans produce up to 3 pints (1.4 liters) of saliva daily, and chemical enzymes in the saliva play a major role in disintegrating starchy foods.

http://science.nationalgeographic.com/science/photos/digestive-system/?source=A-to-Z#/human-mouth_1002_600x450.jpg

Inside the Human MouthPhotograph by Lennart Nilsson

Epiglottis

Image source: http://www.umm.edu/imagepages/19595.htm

Animation

This colored scanning micrograph shows a cast of blood vessels from the external wall of the small intestine.

Measuring about 22 feet (6.7 meters) in length, the small intestine performs most of the major digestion and absorption of nutrients.

The walls of the small intestine are lined with millions of projections called villi, which absorb and transmit nutrients into the bloodstream.

http://science.nationalgeographic.com/science/photos/digestive-system/?source=A-to-Z#/small-intestine-vessels_1211_600x450.jpg

VILLI

Image source: http://www.sciencephoto.com/media/310014/enlarge

BEHAVIOR

http://www.whfoods.com/genpage.php?tname=faq&dbid=16#digestion

Animation of Digestion

http://www.youtube.com/watch?v=vFiavuyk31s&feature=related

Peristalsis video clip

Image source: http://media.photobucket.com/image/peristalsi

s/hurricane78_album/peristalsis.gif?o=2

Wave-like contractions

Image source:

http://www.flickr.com/photos/liujoanne/2172007698/

INTERCONNECTIONDigestion

Absorption Elimination of Waste