SlideShare a Scribd company logo
1 of 34
Biology 30S   Unit 2 DIGESTION  & NUTRITION ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion Recall, many organs of the digestive system secrete different substances. These secretions all play different roles in the chemical digestion of food. During the chemical digestion of food, enzymes break down large food molecules by the process of  hydrolysis . During hydrolysis, a water molecule is added at the site where a bond is broken.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion - Mouth The mouth begins the process of carbohydrate digestion through the action of saliva. The enzyme found in saliva,  salivary amylase , starts the chemical digestion of starch, converting it from a polysaccharide to the disaccharide maltose.
Biology 30S   Unit 2 DIGESTION  & NUTRITION ,[object Object],[object Object],[object Object],[object Object],[object Object]
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion - Stomach A very important constituent of gastric juices is the substance  pepsinogen . Pepsinogen is not an enzyme but a forerunner of the enzyme  pepsin . The hydrochloric acid secreted increases the acidity of the stomach contents to a pH of 2 or lower. At this pH, pepsinogen is converted to pepsin, an active enzyme which begins the chemical digestion of proteins into peptides.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion - Stomach Salivary amylase functions best at pH 6 or 7 (very slightly acidic or neutral). Therefore, it becomes inactive when it reaches the stomach, and consequently, digestion of starch does not take place there. The mucous coats the cells lining the stomach and protects them from the digestive action of the enzyme pepsin.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion – Small Intestine Final digestion of proteins and carbohydrates must occur, and fats have not yet been digested. Villi have cells that produce intestinal enzymes which complete the digestion of peptides and sugars.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion – Small Intestine The upper part, the duodenum, is the most active in digestion. Secretions from the liver and pancreas are used for digestion in the duodenum. Epithelial cells of the duodenum secrete a watery mucous which acts to protect its lining   from pepsin and HCl. The pancreas secretes digestive enzymes and stomach acid-neutralizing  sodium bicarbonate . The sodium bicarbonate neutralizes the acidic chyme, allowing the enzymes in the small intestine to function and protecting the intestinal wall.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion – Small Intestine The liver produces  bile , which is stored in the gall bladder before entering the bile duct into the duodenum. Bile contains cholesterol, phospholipids, bilirubin, and a mix of salts. Bile salts emulsify fats – breaking them down into progressively smaller fat globules until they can be acted upon by fat digesting enzymes. They also aid in neutralizing the chyme from the stomach.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion – Small Intestine The chemical digestion that begins in the small intestine is a result of pancreatic secretions. Starch and glycogen are broken down into maltose through the action of  pancreatic amylase .  Proteases  continue the breakdown of protein that began in the stomach and form small peptide fragments and some amino acids.  Lipases  break down fats into fatty acids and glycerol.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Chemical Digestion – Small Intestine Finally, the villi in the small intestine itself release enzymes which complete the digestive process.  Maltase ,  lactase , and  sucrase  are three carbohydrate digesting enzymes which break down the maltose, sucrose and lactose into monosaccharides. Lactose intolerance results from a lack of the enzyme lactose.  Peptidase  breaks down peptides into amino acids and  nuclease  breaks down nucleic acids into sugars and nitrogen bases.
 
Biology 30S   Unit 2 DIGESTION  & NUTRITION Sites of Chemical Digestion Starch   Mouth and SI Protein   Stomach and SI Fats   SI
Biology 30S   Unit 2 DIGESTION  & NUTRITION Functions of Secretions Besides chemical digestion, certain  secretions of our digestive system serve  other functions. These functions include  the ability to  lubricate  and the ability to  protect  our body.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Functions of Secretions Lubrication  – the mucus found throughout our  digestive system (saliva, stomach, SI) plays a major  role in lubricating food as it passes through the  digestive system. What would happen to the process of digestion if your salivary glands stopped producing saliva?
Biology 30S   Unit 2 DIGESTION  & NUTRITION Functions of Secretions Protection  – the mucus found throughout our  digestive system (saliva, stomach, SI) plays a major  role in protecting our body from the other digestive  secretions of our digestive system. What would happen to the process of digestion if your stomach stopped producing mucus?
Biology 30S   Unit 2 DIGESTION  & NUTRITION ,[object Object],[object Object],[object Object],[object Object],[object Object]
Biology 30S   Unit 2 DIGESTION  & NUTRITION pH The pH of a solution can have several effects on the structure and activity of enzymes. Enzymes are affected by changes in pH. The most favorable pH value - the point where the enzyme is most active - is known as the optimum pH. Extremely high or low pH values generally result in complete loss of activity for most enzymes. pH is also a factor in the stability of enzymes.
Biology 30S   Unit 2 DIGESTION  & NUTRITION
Biology 30S   Unit 2 DIGESTION  & NUTRITION Temperature Like most chemical reactions, the rate of an enzyme-catalyzed reaction increases as the temperature is raised. The reaction rate increases with temperature to a maximum level, then abruptly declines with further increase of temperature.
Biology 30S   Unit 2 DIGESTION  & NUTRITION
Biology 30S   Unit 2 DIGESTION  & NUTRITION Inhibitors Enzyme inhibitors are substances which alter the catalytic action of the enzyme and consequently slow down, or in some cases, stop catalysis. There are three common types of enzyme inhibition - competitive, non-competitive and substrate inhibition.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Control of Digestive Secretions A fascinating feature of the digestive system is that it contains its own regulators, both hormonal and nervous. The major hormones that control the functions of the digestive system are produced and released by cells in the lining of the stomach and small intestine. These hormones are released into the blood of the digestive tract, travel back to the heart and through the arteries, and return to the digestive system, where they stimulate digestive juices and cause organ movement.
Biology 30S   Unit 2 DIGESTION  & NUTRITION ,[object Object],[object Object],[object Object],[object Object],[object Object]
Biology 30S   Unit 2 DIGESTION  & NUTRITION ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Biology 30S   Unit 2 DIGESTION  & NUTRITION
Biology 30S   Unit 2 DIGESTION  & NUTRITION Nervous Control of Digestive Secretions Two types of nerves help to control the action of the digestive system, Extrinsic and Intrinsic. Extrinsic  (outside) nerves come to the digestive organs from the subconscious part of the brain or from the spinal cord.  Intrinsic  (inside) nerves, which make up a very dense network embedded in the walls of the esophagus, stomach, small intestine, and colon.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Extrinsic Nerves These nerves release a chemical called acetylcholine and another called adrenaline. Acetylcholine causes the muscle of the digestive organs to squeeze with more force and increase the "push" of food and juice through the digestive tract. Acetylcholine also causes the stomach and pancreas to produce more digestive juice. Adrenaline relaxes the muscle of the stomach and intestine and decreases the flow of blood to these organs. Seeing, smelling or tasting food produces gastric secretions even before there is food in the stomach.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Intrinsic Nerves The intrinsic nerves are triggered to act when the walls of the hollow organs are stretched by food. They release many different substances that speed up or delay the movement of food and the production of juices by the digestive organs.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Absorption Absorption is a very important part of the digestive process. It allows digested food to be transferred to the bloodstream and transported to the cells in the body. Most absorption occurs in the duodenum and jejunum of the small intestine. However, some water, certain ions, and such drugs as aspirin and ethanol are absorbed from the stomach and large intestine into the blood.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Absorption in Small Intestine The  villi  of the small intestine greatly increase the surface area for absorption. Villi increase the surface area by a factor of 10. The epithelial cells that cover the villi are lined with  microvilli  that further increase the surface area. Absorption through the intestinal wall takes place by diffusion and active transport. Many substances must move through the membranes from an area of low concentration to one of higher concentration. Amino acids, for example, are absorbed by active transport.
Biology 30S   Unit 2 DIGESTION  & NUTRITION Absorption in Small Intestine A thin-walled capillary (small blood vessel) network extends through the core of the villus (singular form of villi). Most dissolved nutrients, which have already been absorbed by passive transport through the epithelial cells, pass into the capillaries. However, the products of fat digestion do not pass into the capillaries, but instead enter a vessel called a  lacteal , which is part of the lymphatic system of the body. The absorbed fat droplets are transported to adipose (fat) tissue where they are stored.
 
Biology 30S   Unit 2 DIGESTION  & NUTRITION Reconstruct a flowchart adding as much information as you can regarding digestion, enzymes, absorption, etc.. Mouth/ Throat Esoph- agus Stomach Small Intestine Large Intestine Rectum/ Anus

More Related Content

What's hot

Hormones and its classification
Hormones and its classificationHormones and its classification
Hormones and its classificationAnup Bajracharya
 
Digestion, absorption and transport of food
Digestion, absorption and transport of foodDigestion, absorption and transport of food
Digestion, absorption and transport of foodArun Geetha Viswanathan
 
Comparative Anatomy - Digestive System
Comparative Anatomy - Digestive SystemComparative Anatomy - Digestive System
Comparative Anatomy - Digestive SystemEmsi Onairpic
 
Chapter 27 Nutrition and Digestion
Chapter 27 Nutrition and DigestionChapter 27 Nutrition and Digestion
Chapter 27 Nutrition and DigestionAthena Anne Scarlet
 
The Digestive System (Chemical Digestion)
The Digestive System (Chemical Digestion)The Digestive System (Chemical Digestion)
The Digestive System (Chemical Digestion)Robert John Bayoneta
 
What is holozoic nutrition
What is holozoic nutritionWhat is holozoic nutrition
What is holozoic nutritionBubly Atif
 
DIGESTION AND ABSORPTION OF CARBOHYDRATES
DIGESTION AND ABSORPTION OF CARBOHYDRATESDIGESTION AND ABSORPTION OF CARBOHYDRATES
DIGESTION AND ABSORPTION OF CARBOHYDRATESRicha Khatiwada
 
Metabolism anabolism & catabolism made easy and simple
Metabolism anabolism & catabolism made easy and simpleMetabolism anabolism & catabolism made easy and simple
Metabolism anabolism & catabolism made easy and simpleMALAKAHMADYOUSAFZAI
 
The digestive system ppt
The digestive system pptThe digestive system ppt
The digestive system pptJonida Kollcaku
 
Digestion & absorption of carbohydrate.pptx
Digestion  & absorption of carbohydrate.pptxDigestion  & absorption of carbohydrate.pptx
Digestion & absorption of carbohydrate.pptxABHIJIT BHOYAR
 
Anatomy and Physiology of GI Tract
Anatomy and Physiology of GI TractAnatomy and Physiology of GI Tract
Anatomy and Physiology of GI TractSagar Savale
 
Digestive system of reptiles, birds and mammals
Digestive system of reptiles, birds and mammalsDigestive system of reptiles, birds and mammals
Digestive system of reptiles, birds and mammalsRittik Garg
 

What's hot (20)

Hormones and its classification
Hormones and its classificationHormones and its classification
Hormones and its classification
 
Digestion, absorption and transport of food
Digestion, absorption and transport of foodDigestion, absorption and transport of food
Digestion, absorption and transport of food
 
Comparative Anatomy - Digestive System
Comparative Anatomy - Digestive SystemComparative Anatomy - Digestive System
Comparative Anatomy - Digestive System
 
Chapter 27 Nutrition and Digestion
Chapter 27 Nutrition and DigestionChapter 27 Nutrition and Digestion
Chapter 27 Nutrition and Digestion
 
Digestion & absorption
Digestion & absorptionDigestion & absorption
Digestion & absorption
 
Human digestive system
Human digestive systemHuman digestive system
Human digestive system
 
Carbohydrates
CarbohydratesCarbohydrates
Carbohydrates
 
Digestion and absorption
Digestion and absorptionDigestion and absorption
Digestion and absorption
 
The Digestive System (Chemical Digestion)
The Digestive System (Chemical Digestion)The Digestive System (Chemical Digestion)
The Digestive System (Chemical Digestion)
 
What is holozoic nutrition
What is holozoic nutritionWhat is holozoic nutrition
What is holozoic nutrition
 
digestion in mouth and swallowing
 digestion in mouth and swallowing   digestion in mouth and swallowing
digestion in mouth and swallowing
 
DIGESTION AND ABSORPTION OF CARBOHYDRATES
DIGESTION AND ABSORPTION OF CARBOHYDRATESDIGESTION AND ABSORPTION OF CARBOHYDRATES
DIGESTION AND ABSORPTION OF CARBOHYDRATES
 
Metabolism anabolism & catabolism made easy and simple
Metabolism anabolism & catabolism made easy and simpleMetabolism anabolism & catabolism made easy and simple
Metabolism anabolism & catabolism made easy and simple
 
The digestive system ppt
The digestive system pptThe digestive system ppt
The digestive system ppt
 
Pineal gland
Pineal glandPineal gland
Pineal gland
 
Digestion & absorption of carbohydrate.pptx
Digestion  & absorption of carbohydrate.pptxDigestion  & absorption of carbohydrate.pptx
Digestion & absorption of carbohydrate.pptx
 
Anatomy and Physiology of GI Tract
Anatomy and Physiology of GI TractAnatomy and Physiology of GI Tract
Anatomy and Physiology of GI Tract
 
SENSE ORGANS
SENSE ORGANSSENSE ORGANS
SENSE ORGANS
 
Digestive system of reptiles, birds and mammals
Digestive system of reptiles, birds and mammalsDigestive system of reptiles, birds and mammals
Digestive system of reptiles, birds and mammals
 
Digestion process
Digestion processDigestion process
Digestion process
 

Similar to Mechanical & Chemical Digestion

Digestion Introduction
Digestion IntroductionDigestion Introduction
Digestion IntroductionBruce Coulter
 
Organs of the Digestive System.pptx
Organs of the Digestive System.pptxOrgans of the Digestive System.pptx
Organs of the Digestive System.pptxFredereck Dominion
 
Introduction to digestion and absorption, local hormones of GIT, different di...
Introduction to digestion and absorption, local hormones of GIT, different di...Introduction to digestion and absorption, local hormones of GIT, different di...
Introduction to digestion and absorption, local hormones of GIT, different di...enamifat
 
Animal Nutrition (www.bioguruindia.com)
Animal Nutrition  (www.bioguruindia.com)Animal Nutrition  (www.bioguruindia.com)
Animal Nutrition (www.bioguruindia.com)sum_itbhu
 
Mechanical And Chemical Digestion Of The Digestive System
Mechanical And Chemical Digestion Of The Digestive SystemMechanical And Chemical Digestion Of The Digestive System
Mechanical And Chemical Digestion Of The Digestive SystemAlyssa Jefferson
 
Sugar Digestion Lab Report
Sugar Digestion Lab ReportSugar Digestion Lab Report
Sugar Digestion Lab ReportAmy Williams
 
Digestive System Yatendra Singh
Digestive System Yatendra SinghDigestive System Yatendra Singh
Digestive System Yatendra SinghYatendra Singh
 
2022 GIT Biochemistry.pptx
2022 GIT Biochemistry.pptx2022 GIT Biochemistry.pptx
2022 GIT Biochemistry.pptxGudetaNoto
 
Human digestive system
Human digestive systemHuman digestive system
Human digestive systemEnigmatic You
 
Digestive System-Physiology.ppt
Digestive System-Physiology.pptDigestive System-Physiology.ppt
Digestive System-Physiology.pptShama
 
CN UNIT MACRONUTRIENTS AND DIGESTION 1.pptx
CN UNIT MACRONUTRIENTS AND DIGESTION 1.pptxCN UNIT MACRONUTRIENTS AND DIGESTION 1.pptx
CN UNIT MACRONUTRIENTS AND DIGESTION 1.pptxJessicaMoses12
 
Presentation part a
Presentation part aPresentation part a
Presentation part aMathew Haine
 
1.digestive juices
1.digestive juices1.digestive juices
1.digestive juicesTanvi Naik
 
753 Learning OutcomesAfter reading this chapter, .docx
753 Learning OutcomesAfter reading this chapter, .docx753 Learning OutcomesAfter reading this chapter, .docx
753 Learning OutcomesAfter reading this chapter, .docxpoulterbarbara
 
pancreatic secretions.pptx
pancreatic secretions.pptxpancreatic secretions.pptx
pancreatic secretions.pptxFatimaSundus1
 
Digestive System Teacher
Digestive System TeacherDigestive System Teacher
Digestive System TeacherF Blanco
 
BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2
BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2
BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2Nirmala Josephine
 

Similar to Mechanical & Chemical Digestion (20)

Digestion Introduction
Digestion IntroductionDigestion Introduction
Digestion Introduction
 
Digestive system
Digestive systemDigestive system
Digestive system
 
Organs of the Digestive System.pptx
Organs of the Digestive System.pptxOrgans of the Digestive System.pptx
Organs of the Digestive System.pptx
 
Introduction to digestion and absorption, local hormones of GIT, different di...
Introduction to digestion and absorption, local hormones of GIT, different di...Introduction to digestion and absorption, local hormones of GIT, different di...
Introduction to digestion and absorption, local hormones of GIT, different di...
 
Animal Nutrition (www.bioguruindia.com)
Animal Nutrition  (www.bioguruindia.com)Animal Nutrition  (www.bioguruindia.com)
Animal Nutrition (www.bioguruindia.com)
 
Mechanical And Chemical Digestion Of The Digestive System
Mechanical And Chemical Digestion Of The Digestive SystemMechanical And Chemical Digestion Of The Digestive System
Mechanical And Chemical Digestion Of The Digestive System
 
Sugar Digestion Lab Report
Sugar Digestion Lab ReportSugar Digestion Lab Report
Sugar Digestion Lab Report
 
Digestive System Yatendra Singh
Digestive System Yatendra SinghDigestive System Yatendra Singh
Digestive System Yatendra Singh
 
2022 GIT Biochemistry.pptx
2022 GIT Biochemistry.pptx2022 GIT Biochemistry.pptx
2022 GIT Biochemistry.pptx
 
Human digestive system
Human digestive systemHuman digestive system
Human digestive system
 
Digestive System-Physiology.ppt
Digestive System-Physiology.pptDigestive System-Physiology.ppt
Digestive System-Physiology.ppt
 
CN UNIT MACRONUTRIENTS AND DIGESTION 1.pptx
CN UNIT MACRONUTRIENTS AND DIGESTION 1.pptxCN UNIT MACRONUTRIENTS AND DIGESTION 1.pptx
CN UNIT MACRONUTRIENTS AND DIGESTION 1.pptx
 
Presentation part a
Presentation part aPresentation part a
Presentation part a
 
Digestive system i
Digestive system iDigestive system i
Digestive system i
 
Digestive system i
Digestive system iDigestive system i
Digestive system i
 
1.digestive juices
1.digestive juices1.digestive juices
1.digestive juices
 
753 Learning OutcomesAfter reading this chapter, .docx
753 Learning OutcomesAfter reading this chapter, .docx753 Learning OutcomesAfter reading this chapter, .docx
753 Learning OutcomesAfter reading this chapter, .docx
 
pancreatic secretions.pptx
pancreatic secretions.pptxpancreatic secretions.pptx
pancreatic secretions.pptx
 
Digestive System Teacher
Digestive System TeacherDigestive System Teacher
Digestive System Teacher
 
BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2
BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2
BIOLOGY FORM 4 CHAPTER 6 - NUTRITION PART 2
 

More from Bruce Coulter

More from Bruce Coulter (20)

Unit 4 Notes
Unit 4 NotesUnit 4 Notes
Unit 4 Notes
 
Unit 5 Notes
Unit 5 NotesUnit 5 Notes
Unit 5 Notes
 
Respiration Notes
Respiration NotesRespiration Notes
Respiration Notes
 
Kinematics 2012
Kinematics 2012Kinematics 2012
Kinematics 2012
 
The Heart
The HeartThe Heart
The Heart
 
Managing Money
Managing Money Managing Money
Managing Money
 
Unit 3 Statistics
Unit 3 Statistics Unit 3 Statistics
Unit 3 Statistics
 
Vehicle Finance
Vehicle Finance Vehicle Finance
Vehicle Finance
 
Unit 3 Precision Measurement
Unit 3  Precision MeasurementUnit 3  Precision Measurement
Unit 3 Precision Measurement
 
Unit 2 Notes
Unit 2 NotesUnit 2 Notes
Unit 2 Notes
 
Unit 2 3D Geometry
Unit 2 3D GeometryUnit 2 3D Geometry
Unit 2 3D Geometry
 
Unit 1 Interest & Credit
Unit 1   Interest & CreditUnit 1   Interest & Credit
Unit 1 Interest & Credit
 
Unit 2 - Statistics
Unit 2 - StatisticsUnit 2 - Statistics
Unit 2 - Statistics
 
Unit 1 Home Finance
Unit 1   Home FinanceUnit 1   Home Finance
Unit 1 Home Finance
 
Chem 40S Unit 5 Notes
Chem 40S Unit 5 NotesChem 40S Unit 5 Notes
Chem 40S Unit 5 Notes
 
Chem 40S Unit 4 Notes
Chem 40S Unit 4 NotesChem 40S Unit 4 Notes
Chem 40S Unit 4 Notes
 
Chem 40S Unit 3 Notes
Chem 40S Unit 3 NotesChem 40S Unit 3 Notes
Chem 40S Unit 3 Notes
 
Chem 40Ss Unit 2 Notes
Chem 40Ss Unit 2 NotesChem 40Ss Unit 2 Notes
Chem 40Ss Unit 2 Notes
 
Chem 40S Uunit 1 Notes
Chem 40S Uunit 1 NotesChem 40S Uunit 1 Notes
Chem 40S Uunit 1 Notes
 
Unit 5 Immune System
Unit 5 Immune SystemUnit 5 Immune System
Unit 5 Immune System
 

Recently uploaded

CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...Nguyen Thanh Tu Collection
 
How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17Celine George
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxDr. Asif Anas
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17Celine George
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapitolTechU
 
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxPractical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxKatherine Villaluna
 
How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17Celine George
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...raviapr7
 
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptxSandy Millin
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.raviapr7
 
Diploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfDiploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfMohonDas
 
Education and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptxEducation and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptxraviapr7
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?TechSoup
 
M-2- General Reactions of amino acids.pptx
M-2- General Reactions of amino acids.pptxM-2- General Reactions of amino acids.pptx
M-2- General Reactions of amino acids.pptxDr. Santhosh Kumar. N
 
Philosophy of Education and Educational Philosophy
Philosophy of Education  and Educational PhilosophyPhilosophy of Education  and Educational Philosophy
Philosophy of Education and Educational PhilosophyShuvankar Madhu
 
Benefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationBenefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationMJDuyan
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfYu Kanazawa / Osaka University
 
5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...CaraSkikne1
 

Recently uploaded (20)

Personal Resilience in Project Management 2 - TV Edit 1a.pdf
Personal Resilience in Project Management 2 - TV Edit 1a.pdfPersonal Resilience in Project Management 2 - TV Edit 1a.pdf
Personal Resilience in Project Management 2 - TV Edit 1a.pdf
 
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
 
How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17How to Show Error_Warning Messages in Odoo 17
How to Show Error_Warning Messages in Odoo 17
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptx
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptx
 
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxPractical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
 
How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...
 
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.
 
Diploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfDiploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdf
 
Education and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptxEducation and training program in the hospital APR.pptx
Education and training program in the hospital APR.pptx
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?
 
M-2- General Reactions of amino acids.pptx
M-2- General Reactions of amino acids.pptxM-2- General Reactions of amino acids.pptx
M-2- General Reactions of amino acids.pptx
 
Prelims of Kant get Marx 2.0: a general politics quiz
Prelims of Kant get Marx 2.0: a general politics quizPrelims of Kant get Marx 2.0: a general politics quiz
Prelims of Kant get Marx 2.0: a general politics quiz
 
Philosophy of Education and Educational Philosophy
Philosophy of Education  and Educational PhilosophyPhilosophy of Education  and Educational Philosophy
Philosophy of Education and Educational Philosophy
 
Benefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationBenefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive Education
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
 
5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...
 

Mechanical & Chemical Digestion

  • 1.
  • 2. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion Recall, many organs of the digestive system secrete different substances. These secretions all play different roles in the chemical digestion of food. During the chemical digestion of food, enzymes break down large food molecules by the process of hydrolysis . During hydrolysis, a water molecule is added at the site where a bond is broken.
  • 3. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion - Mouth The mouth begins the process of carbohydrate digestion through the action of saliva. The enzyme found in saliva, salivary amylase , starts the chemical digestion of starch, converting it from a polysaccharide to the disaccharide maltose.
  • 4.
  • 5. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion - Stomach A very important constituent of gastric juices is the substance pepsinogen . Pepsinogen is not an enzyme but a forerunner of the enzyme pepsin . The hydrochloric acid secreted increases the acidity of the stomach contents to a pH of 2 or lower. At this pH, pepsinogen is converted to pepsin, an active enzyme which begins the chemical digestion of proteins into peptides.
  • 6. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion - Stomach Salivary amylase functions best at pH 6 or 7 (very slightly acidic or neutral). Therefore, it becomes inactive when it reaches the stomach, and consequently, digestion of starch does not take place there. The mucous coats the cells lining the stomach and protects them from the digestive action of the enzyme pepsin.
  • 7. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion – Small Intestine Final digestion of proteins and carbohydrates must occur, and fats have not yet been digested. Villi have cells that produce intestinal enzymes which complete the digestion of peptides and sugars.
  • 8. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion – Small Intestine The upper part, the duodenum, is the most active in digestion. Secretions from the liver and pancreas are used for digestion in the duodenum. Epithelial cells of the duodenum secrete a watery mucous which acts to protect its lining from pepsin and HCl. The pancreas secretes digestive enzymes and stomach acid-neutralizing sodium bicarbonate . The sodium bicarbonate neutralizes the acidic chyme, allowing the enzymes in the small intestine to function and protecting the intestinal wall.
  • 9. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion – Small Intestine The liver produces bile , which is stored in the gall bladder before entering the bile duct into the duodenum. Bile contains cholesterol, phospholipids, bilirubin, and a mix of salts. Bile salts emulsify fats – breaking them down into progressively smaller fat globules until they can be acted upon by fat digesting enzymes. They also aid in neutralizing the chyme from the stomach.
  • 10. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion – Small Intestine The chemical digestion that begins in the small intestine is a result of pancreatic secretions. Starch and glycogen are broken down into maltose through the action of pancreatic amylase . Proteases continue the breakdown of protein that began in the stomach and form small peptide fragments and some amino acids. Lipases break down fats into fatty acids and glycerol.
  • 11. Biology 30S Unit 2 DIGESTION & NUTRITION Chemical Digestion – Small Intestine Finally, the villi in the small intestine itself release enzymes which complete the digestive process. Maltase , lactase , and sucrase are three carbohydrate digesting enzymes which break down the maltose, sucrose and lactose into monosaccharides. Lactose intolerance results from a lack of the enzyme lactose. Peptidase breaks down peptides into amino acids and nuclease breaks down nucleic acids into sugars and nitrogen bases.
  • 12.  
  • 13. Biology 30S Unit 2 DIGESTION & NUTRITION Sites of Chemical Digestion Starch Mouth and SI Protein Stomach and SI Fats SI
  • 14. Biology 30S Unit 2 DIGESTION & NUTRITION Functions of Secretions Besides chemical digestion, certain secretions of our digestive system serve other functions. These functions include the ability to lubricate and the ability to protect our body.
  • 15. Biology 30S Unit 2 DIGESTION & NUTRITION Functions of Secretions Lubrication – the mucus found throughout our digestive system (saliva, stomach, SI) plays a major role in lubricating food as it passes through the digestive system. What would happen to the process of digestion if your salivary glands stopped producing saliva?
  • 16. Biology 30S Unit 2 DIGESTION & NUTRITION Functions of Secretions Protection – the mucus found throughout our digestive system (saliva, stomach, SI) plays a major role in protecting our body from the other digestive secretions of our digestive system. What would happen to the process of digestion if your stomach stopped producing mucus?
  • 17.
  • 18. Biology 30S Unit 2 DIGESTION & NUTRITION pH The pH of a solution can have several effects on the structure and activity of enzymes. Enzymes are affected by changes in pH. The most favorable pH value - the point where the enzyme is most active - is known as the optimum pH. Extremely high or low pH values generally result in complete loss of activity for most enzymes. pH is also a factor in the stability of enzymes.
  • 19. Biology 30S Unit 2 DIGESTION & NUTRITION
  • 20. Biology 30S Unit 2 DIGESTION & NUTRITION Temperature Like most chemical reactions, the rate of an enzyme-catalyzed reaction increases as the temperature is raised. The reaction rate increases with temperature to a maximum level, then abruptly declines with further increase of temperature.
  • 21. Biology 30S Unit 2 DIGESTION & NUTRITION
  • 22. Biology 30S Unit 2 DIGESTION & NUTRITION Inhibitors Enzyme inhibitors are substances which alter the catalytic action of the enzyme and consequently slow down, or in some cases, stop catalysis. There are three common types of enzyme inhibition - competitive, non-competitive and substrate inhibition.
  • 23. Biology 30S Unit 2 DIGESTION & NUTRITION Control of Digestive Secretions A fascinating feature of the digestive system is that it contains its own regulators, both hormonal and nervous. The major hormones that control the functions of the digestive system are produced and released by cells in the lining of the stomach and small intestine. These hormones are released into the blood of the digestive tract, travel back to the heart and through the arteries, and return to the digestive system, where they stimulate digestive juices and cause organ movement.
  • 24.
  • 25.
  • 26. Biology 30S Unit 2 DIGESTION & NUTRITION
  • 27. Biology 30S Unit 2 DIGESTION & NUTRITION Nervous Control of Digestive Secretions Two types of nerves help to control the action of the digestive system, Extrinsic and Intrinsic. Extrinsic (outside) nerves come to the digestive organs from the subconscious part of the brain or from the spinal cord. Intrinsic (inside) nerves, which make up a very dense network embedded in the walls of the esophagus, stomach, small intestine, and colon.
  • 28. Biology 30S Unit 2 DIGESTION & NUTRITION Extrinsic Nerves These nerves release a chemical called acetylcholine and another called adrenaline. Acetylcholine causes the muscle of the digestive organs to squeeze with more force and increase the "push" of food and juice through the digestive tract. Acetylcholine also causes the stomach and pancreas to produce more digestive juice. Adrenaline relaxes the muscle of the stomach and intestine and decreases the flow of blood to these organs. Seeing, smelling or tasting food produces gastric secretions even before there is food in the stomach.
  • 29. Biology 30S Unit 2 DIGESTION & NUTRITION Intrinsic Nerves The intrinsic nerves are triggered to act when the walls of the hollow organs are stretched by food. They release many different substances that speed up or delay the movement of food and the production of juices by the digestive organs.
  • 30. Biology 30S Unit 2 DIGESTION & NUTRITION Absorption Absorption is a very important part of the digestive process. It allows digested food to be transferred to the bloodstream and transported to the cells in the body. Most absorption occurs in the duodenum and jejunum of the small intestine. However, some water, certain ions, and such drugs as aspirin and ethanol are absorbed from the stomach and large intestine into the blood.
  • 31. Biology 30S Unit 2 DIGESTION & NUTRITION Absorption in Small Intestine The villi of the small intestine greatly increase the surface area for absorption. Villi increase the surface area by a factor of 10. The epithelial cells that cover the villi are lined with microvilli that further increase the surface area. Absorption through the intestinal wall takes place by diffusion and active transport. Many substances must move through the membranes from an area of low concentration to one of higher concentration. Amino acids, for example, are absorbed by active transport.
  • 32. Biology 30S Unit 2 DIGESTION & NUTRITION Absorption in Small Intestine A thin-walled capillary (small blood vessel) network extends through the core of the villus (singular form of villi). Most dissolved nutrients, which have already been absorbed by passive transport through the epithelial cells, pass into the capillaries. However, the products of fat digestion do not pass into the capillaries, but instead enter a vessel called a lacteal , which is part of the lymphatic system of the body. The absorbed fat droplets are transported to adipose (fat) tissue where they are stored.
  • 33.  
  • 34. Biology 30S Unit 2 DIGESTION & NUTRITION Reconstruct a flowchart adding as much information as you can regarding digestion, enzymes, absorption, etc.. Mouth/ Throat Esoph- agus Stomach Small Intestine Large Intestine Rectum/ Anus