Mechanical and chemical digestion. What is Mechanical Digestion?  Mechanical digestion : the movement and breakdown of food (for example, tearing, smashing).

Slides:

Advertisements

Similar presentations

The Human Digestive System

Advertisements

REVIEW Digestion.

The Digestive System Organs

FROM FOOD TO FUEL. As discussed: Many factors influnce our choice of foods. These include not only what we choose to eat, but also: When we choose to.

Topic: Human Digestive System. The human digestive system is a system of organs and glands which digest and absorb food and its nutrients. There are two.

The Digestive System.

The Digestive System Guts, teeth and glands! Images from:

Human Digestive System (Hope you don’t find this too hard to digest)

The Digestive System Chapter 29 Think about sliding a warm, tasty slice of cheese pizza into your mouth. You take a bite, chew, and swallow. You probably.

DIGESTION The process of preparing your food for absorption bin/netquiz_get.pl?qfooter=/usr/web/home/mhhe/biosci/genbio/animation_quizz.

Quaestio: How do humans obtain and process nutrients?

Digestive System Chapter 18.

DIGESTIVE SYSTEM Professor Andrea Garrison Biology 11

Digestive System: From Mouth to Anus

Lesson 1 Transport and Defense

Digestion Mechanical and Chemical Breakdown of Ingested Food.

Digestive System Notes. Mouth Carbohydrate digestion begins here! Ingestion = eating.

Do Now: What is this a picture of? List your top 3 guesses.

Digestion Clip by Brainpop. Nutrients… Are substances in food that provide energy and materials for cell development, growth, and repair.

Liz Lauben 1 Digestion Liz Lauben 2 Introduction Digestion is defined as the breakdown of nutrients We consume: Proteins Carbohydrates Fats These are.

PP  Breakdown of food into simpler molecules that can be absorbed by the body in one long tube from mouth to anus.

The Digestive System Oral cavity Pharynx Esophagus Liver Stomach

Human Digestion.

The Digestive System Lab

Digestive enzymes Recap Starch Proteins Lipids/ Fats maltose

The Digestive System 3.5 & 3.6.

Digestive System. Mouth Esophogus Liver Anus Stomach Pancreas Large intestine Small intestine Rectum.

The Digestive System. Purpose of digestive system: –Converts food into small molecules that can be used by cells!! –Why do the food molecules need to.

Breaks down food into nutrients.

The Digestive System The Functions of the Digestive System 1.Ingestion: when food enters the mouth 2.Digestion: when food is broken down 3.Absorption:

The Digestive System.

Why do we need food? Gives us energy to function. Provides body with materials to grow and repair tissue. Nutrients – Carbohydrates (CHO), fats, proteins,

THE DIGESTIVE SYSTEM.

Digestive System. Humans as Heterotrophs Hetero=another Trophe= nutrition As heterotrophs we cannot create carbon, therefore we need to ingest carbon.

Digestive System Breaking down food to be used by the body.

Human Anatomy and Physiology The Digestive System.

© 2006 Plano ISD, Plano, TX. Digestive System a coiled, muscular tube (6-9 meters long) beginning with the mouth and ending with the anus.

Dinner Is Served Remember the last time you sat down to a dinner of your favorite foods? Recall everything that you did before you swallowed your first.

The Human Digestive System. The Mouth Structure: see diagram Function: Ingest and Digest Ingestion - the teeth and tongue (taste buds) take in the appropriate.

Human Digestion.

Mouth Mechanical Digestion –Teeth and tongue break food down into smaller pieces Chemical Digestion –Salivary glands produce saliva –Chemicals (Enzymes)

Digestive System.

The Digestive System Part II Structures, Functions & Enzymes.

Digestion Chapter 38 page 987. There are four parts to digestion: 1.Ingestion – taking in of nutrients 2.Digestion – breakdown of large organic molecules.

CHAPTER 48 SECTIONS 1 & 2 PP DIGESTIVE SYSTEM Warm-up: 5/14 What is the pathway for the respirator system, starting with the mouth and ending with.

The Digestive System.

The Digestive System. Digestion  Digestion: is the process of breaking down food into molecules the body can use, the absorption of nutrients, & the.

UNIT 4 ANIMALS STRUCTURE & FUNCTION. Four stages of food processing 1.Ingestion: taking in/eating of food 1.Digestion: breaking down food (mechanically/chemically)

Chapter 38. Functions of the Digestive System To ingest food Digest food Force food along digestive tract Absorbs nutrients from the digested food Eliminates.

NOTES – DIGESTIVE SYSTEM ANATOMY. Within 2-6 hours, all food is emptied into the small intestine. After you eat how long does it take for the stomach.

The Digestive System. What is digestion? How is the food we consume digested?

Digestive System Frog vs. Human.

THE DIGESTIVE SYSTEM A.K.A. THE GASTROINTESTINAL (GI) TRACT Converts foods into simpler molecules, then absorbs them into the blood stream for use by.

HOMEOSTASIS AND THE DIGESTIVE SYSTEM Essential Questions: How do living organisms maintain a relatively constant internal environment when outside conditions.

The Digestive System Digestion is the process of converting food substances to a state in which they can be absorbed by the lining of the digestive tract.

The Digestive System Organs

Breaks down food into nutrients.

Producing these end products

The Digestive System.

Copyright Pearson Prentice Hall

Mechanical vs. Chemical Digestion

BrainPOP | Digestive System

Section 38.2 The Digestive System

DIGESTION SBI 3C: NOVEMBER 2010.

NOTES – DIGESTIVE SYSTEM ANATOMY

NOTES – DIGESTIVE SYSTEM ANATOMY

Digestive System pp. 183 to 190.

Digestive System Parts and Functions.

PP DIGESTIVE SYSTEM.

digestion – the chemical and mechanical breakdown of food

Presentation transcript:

Mechanical and chemical digestion

What is Mechanical Digestion?  Mechanical digestion : the movement and breakdown of food (for example, tearing, smashing).  There are two basic types of mechanical digestion.  Mastication : chewing begins the process of breaking down food into nutrients.  Peristalsis : is the involuntary contractions responsible for the movement of food through the esophagus and intestinal tracts.

Watch this video clip  chapter26/animation__organs_of_digestion.html chapter26/animation__organs_of_digestion.html

What is Chemical Digestion?  enzymes are needed to chemically digest the large molecules: carbohydrates  monosaccharides lipids  fatty acids & glycerol proteins  amino acids  once digested, the nutrients can be absorbed  the other types of nutrients (vitamins, minerals, water) can be absorbed directly without being digested

The mouth- salivary glands  secrete saliva  saliva contains: mucins for lubrication  amylase for digesting starch  the chewed bolus is pushed into the pharynx and swallowed

Stomach  the stomach is lined with millions of gastric glands  parietal cells:  secrete hydrochloric acid (pH = 1 to 2)  The acid kills some bacteria, denatures protein, breaks down tissue, activates the enzyme pepsin  chief cells:  secrete pepsinogen – which is activated by the acid to form the enzyme pepsin  pepsin digests proteins into smaller polypeptide chains

Small intestine  long, thin, muscular tube (7 m long)  three major sections:  duodenum – receives secretions from pancreas and liver  jejunum – most digestion occurs here; some absorption  ileum – most absorption occurs here

Duodenum bile: produced in liver, stored in gall bladder composed of salts, pigments and cholesterol (NOT an enzyme!) emulsifies fats: physically breaks down large fat droplets into smaller fat droplets digestive enzymes: produced in the pancreas and sodium bicarbonate: from pancreas neutralizes acid, raises pH to 8 activates intestinal enzymes

Jejunum & Ileum  secrete more digestive enzymes from intestinal glands  also is the major site for nutrient absorption

How Long Does it Take to Digest Food?  In healthy adults, this process can range from hours but the average is about 36.  Typically, after ingestion, food remains in the stomach and small intestine from 6-8 hours.  The large intestine is capable of holding undigested food waste for days.