"Digestive System is a system by which ingested food is acted upon by physical and chemical means to provide the body with absorb-able nutrients and to excrete waste products."
The human digestive system consists of two major component one is the accessory organ like liver pancreas gall bladder salivary gland and other is the Alimentary canal which is started from oral cavity and ends on anal cavity.
in this ppt all parts are described briefly for better understanding.
The Ultimate Guide to Understanding the Human Digestive SystemDeepanshuYadav2
Human Digestive System: Unraveling the Intricacies of our Inner Factory
Introduction
Welcome to this comprehensive guide on the human digestive system! In this article, we will embark on a fascinating journey through the intricacies of our inner factory, exploring the processes and functions that allow our bodies to break down and absorb nutrients from the food we consume. Join us as we unravel the secrets of digestion, absorption, and elimination, shedding light on the marvelous mechanism that keeps us nourished and energized.
The Human Digestive System: An Overview
The human digestive system is a complex network of organs and processes that work together to facilitate the digestion and absorption of food. From the moment we take a bite to the final elimination of waste, this remarkable system ensures that our bodies receive the vital nutrients needed for growth, repair, and maintenance.
The Mouth: Where It All Begins
The journey of digestion commences in the mouth. As food enters our oral cavity, it undergoes the first stage of mechanical digestion through the process of chewing. The teeth break down the food into smaller pieces, increasing its surface area for efficient chemical digestion. The saliva, secreted by the salivary glands, also plays a crucial role by moistening the food and initiating the breakdown of complex carbohydrates with the enzyme amylase.
The Esophagus: A Pathway to the Stomach
Once food is sufficiently chewed and mixed with saliva, it travels down the esophagus, a muscular tube connecting the mouth to the stomach. Through rhythmic contractions known as peristalsis, the esophagus propels the food downward, allowing it to reach the stomach for further processing.
The Stomach: A Gastric Playground
The stomach serves as a temporary reservoir for food and facilitates both mechanical and chemical digestion. It churns and mixes the food with gastric juices, including hydrochloric acid and enzymes such as pepsin. This powerful combination breaks down proteins and kills harmful bacteria, preparing the food for the next phase of digestion.
The Small Intestine: The Hub of Absorption
The small intestine is where the magic of absorption truly takes place. Divided into three parts—the duodenum, jejunum, and ileum—it receives the partially digested food from the stomach. The walls of the small intestine are lined with finger-like projections called villi, which increase the surface area for nutrient absorption. Here, the nutrients are broken down into their smallest forms and are transported into the bloodstream for distribution to the body's cells.
The Large Intestine: Processing Waste
As the now-depleted food mass enters the large intestine, the focus shifts from digestion to waste processing. The large intestine absorbs water and electrolytes from the remaining undigested material, forming solid waste known as feces. The feces are then stored in the rectum until elimination through the anus occurs.
1. absorption: passage of digested products from the intestinal lumen through mucosal cells and into the bloodstream or lacteals
2. chemical digestion: enzymatic breakdown of food
3. chyme: soupy liquid created when food is mixed with
digestive juices
4. defecation: elimination of undigested substances from the
body in the form of feces
5. ingestion: taking food into the GI tract through the mouth
6. mastication: chewing
7. mechanical digestion: chewing, mixing, and segmentation
that prepares food for chemical digestion
8. peristalsis: muscular contractions and relaxations that propel
food through the GI tract
9. propulsion: voluntary process of swallowing and the
involuntary process of peristalsis that moves food through the
digestive tract
10. segmentation: alternating contractions and relaxations of
non-adjacent segments of the intestine that move food
forward and backward, breaking it apart and mixing it with
digestive juices
Digestion and absorption, digestive secretions, their characteristic features: Digestion is the breakdown of food into particles small enough to cross the cellular barrier of the gastrointestinal (GI) system and be carried around the body in the circulation.
This occurs by both mechanical and chemical processes that begin in the mouth and generally end in the small intestine, where 90% of absorption takes place.
The other 10% takes place in the stomach and large intestine and often involves the help of the gut microbiota.
A small amount of absorption is also thought to take place in the mouth.
Mechanical digestion begins in the mouth with chewing and continues with segmental muscle contractions in the stomach and intestines.
Chemical digestion is primarily mediated by enzymes present in the secretions of the salivary glands, stomach and pancreas, and on the epithelial lining of the small intestine
Mechanical digestion is physical process in which food is broken into smaller pieces without chemically.
It begins with our first bite of food and continues as we chew food with our teeth into smaller pieces.
The process of mechanical digestion continues in the stomach. This muscular organ churns and mixes the food it contains, an action that breaks any solid food into still smaller pieces.
Chemical digestion is the biochemical process in which macromolecules in food are changed into smaller molecules that can be absorbed into body fluids and transported to cells throughout the body.
Substances in food that must be chemically digested include carbohydrates, proteins, lipids, and nucleic acids.
Carbohydrates must be broken down into simple sugars, proteins into amino acids, lipids into fatty acids and glycerol, and nucleic acids into nitrogen bases and sugars.
Some chemical digestion takes place in the mouth and stomach, but most of it occurs in the first part of the small intestine (duodenum).
Chemical digestion could not occur without the help of many different digestive enzymes. Enzymes are proteins that catalyze or speed up biochemical reactions.
Digestive enzymes are secreted by exocrine glands or by the mucosal layer of the epithelium lining the gastrointestinal tract.
In the mouth, digestive enzymes are secreted by salivary glands.
The lining of the stomach secretes enzymes, as does the lining of the small intestine.
Many more digestive enzymes are secreted by exocrine cells in the pancreas and carried by ducts to the small intestine
About 80 percent of digestible carbohydrates in a typical Western diet are in the form of the plant polysaccharide amylose, which consists mainly of long chains of glucose and is one of two major components of starch.
Additional dietary carbohydrates include the animal polysaccharide glycogen, along with some sugars, which are mainly disaccharides.
To chemically digest amylose and glycogen, the enzyme amylase is required. The chemical digestion of these polysaccharides begins in the mou
"Digestive System is a system by which ingested food is acted upon by physical and chemical means to provide the body with absorb-able nutrients and to excrete waste products."
The human digestive system consists of two major component one is the accessory organ like liver pancreas gall bladder salivary gland and other is the Alimentary canal which is started from oral cavity and ends on anal cavity.
in this ppt all parts are described briefly for better understanding.
The Ultimate Guide to Understanding the Human Digestive SystemDeepanshuYadav2
Human Digestive System: Unraveling the Intricacies of our Inner Factory
Introduction
Welcome to this comprehensive guide on the human digestive system! In this article, we will embark on a fascinating journey through the intricacies of our inner factory, exploring the processes and functions that allow our bodies to break down and absorb nutrients from the food we consume. Join us as we unravel the secrets of digestion, absorption, and elimination, shedding light on the marvelous mechanism that keeps us nourished and energized.
The Human Digestive System: An Overview
The human digestive system is a complex network of organs and processes that work together to facilitate the digestion and absorption of food. From the moment we take a bite to the final elimination of waste, this remarkable system ensures that our bodies receive the vital nutrients needed for growth, repair, and maintenance.
The Mouth: Where It All Begins
The journey of digestion commences in the mouth. As food enters our oral cavity, it undergoes the first stage of mechanical digestion through the process of chewing. The teeth break down the food into smaller pieces, increasing its surface area for efficient chemical digestion. The saliva, secreted by the salivary glands, also plays a crucial role by moistening the food and initiating the breakdown of complex carbohydrates with the enzyme amylase.
The Esophagus: A Pathway to the Stomach
Once food is sufficiently chewed and mixed with saliva, it travels down the esophagus, a muscular tube connecting the mouth to the stomach. Through rhythmic contractions known as peristalsis, the esophagus propels the food downward, allowing it to reach the stomach for further processing.
The Stomach: A Gastric Playground
The stomach serves as a temporary reservoir for food and facilitates both mechanical and chemical digestion. It churns and mixes the food with gastric juices, including hydrochloric acid and enzymes such as pepsin. This powerful combination breaks down proteins and kills harmful bacteria, preparing the food for the next phase of digestion.
The Small Intestine: The Hub of Absorption
The small intestine is where the magic of absorption truly takes place. Divided into three parts—the duodenum, jejunum, and ileum—it receives the partially digested food from the stomach. The walls of the small intestine are lined with finger-like projections called villi, which increase the surface area for nutrient absorption. Here, the nutrients are broken down into their smallest forms and are transported into the bloodstream for distribution to the body's cells.
The Large Intestine: Processing Waste
As the now-depleted food mass enters the large intestine, the focus shifts from digestion to waste processing. The large intestine absorbs water and electrolytes from the remaining undigested material, forming solid waste known as feces. The feces are then stored in the rectum until elimination through the anus occurs.
1. absorption: passage of digested products from the intestinal lumen through mucosal cells and into the bloodstream or lacteals
2. chemical digestion: enzymatic breakdown of food
3. chyme: soupy liquid created when food is mixed with
digestive juices
4. defecation: elimination of undigested substances from the
body in the form of feces
5. ingestion: taking food into the GI tract through the mouth
6. mastication: chewing
7. mechanical digestion: chewing, mixing, and segmentation
that prepares food for chemical digestion
8. peristalsis: muscular contractions and relaxations that propel
food through the GI tract
9. propulsion: voluntary process of swallowing and the
involuntary process of peristalsis that moves food through the
digestive tract
10. segmentation: alternating contractions and relaxations of
non-adjacent segments of the intestine that move food
forward and backward, breaking it apart and mixing it with
digestive juices
Digestion and absorption, digestive secretions, their characteristic features: Digestion is the breakdown of food into particles small enough to cross the cellular barrier of the gastrointestinal (GI) system and be carried around the body in the circulation.
This occurs by both mechanical and chemical processes that begin in the mouth and generally end in the small intestine, where 90% of absorption takes place.
The other 10% takes place in the stomach and large intestine and often involves the help of the gut microbiota.
A small amount of absorption is also thought to take place in the mouth.
Mechanical digestion begins in the mouth with chewing and continues with segmental muscle contractions in the stomach and intestines.
Chemical digestion is primarily mediated by enzymes present in the secretions of the salivary glands, stomach and pancreas, and on the epithelial lining of the small intestine
Mechanical digestion is physical process in which food is broken into smaller pieces without chemically.
It begins with our first bite of food and continues as we chew food with our teeth into smaller pieces.
The process of mechanical digestion continues in the stomach. This muscular organ churns and mixes the food it contains, an action that breaks any solid food into still smaller pieces.
Chemical digestion is the biochemical process in which macromolecules in food are changed into smaller molecules that can be absorbed into body fluids and transported to cells throughout the body.
Substances in food that must be chemically digested include carbohydrates, proteins, lipids, and nucleic acids.
Carbohydrates must be broken down into simple sugars, proteins into amino acids, lipids into fatty acids and glycerol, and nucleic acids into nitrogen bases and sugars.
Some chemical digestion takes place in the mouth and stomach, but most of it occurs in the first part of the small intestine (duodenum).
Chemical digestion could not occur without the help of many different digestive enzymes. Enzymes are proteins that catalyze or speed up biochemical reactions.
Digestive enzymes are secreted by exocrine glands or by the mucosal layer of the epithelium lining the gastrointestinal tract.
In the mouth, digestive enzymes are secreted by salivary glands.
The lining of the stomach secretes enzymes, as does the lining of the small intestine.
Many more digestive enzymes are secreted by exocrine cells in the pancreas and carried by ducts to the small intestine
About 80 percent of digestible carbohydrates in a typical Western diet are in the form of the plant polysaccharide amylose, which consists mainly of long chains of glucose and is one of two major components of starch.
Additional dietary carbohydrates include the animal polysaccharide glycogen, along with some sugars, which are mainly disaccharides.
To chemically digest amylose and glycogen, the enzyme amylase is required. The chemical digestion of these polysaccharides begins in the mou
CHAPTER 1 SEMESTER V - ROLE OF PEADIATRIC NURSE.pdfSachin Sharma
Pediatric nurses play a vital role in the health and well-being of children. Their responsibilities are wide-ranging, and their objectives can be categorized into several key areas:
1. Direct Patient Care:
Objective: Provide comprehensive and compassionate care to infants, children, and adolescents in various healthcare settings (hospitals, clinics, etc.).
This includes tasks like:
Monitoring vital signs and physical condition.
Administering medications and treatments.
Performing procedures as directed by doctors.
Assisting with daily living activities (bathing, feeding).
Providing emotional support and pain management.
2. Health Promotion and Education:
Objective: Promote healthy behaviors and educate children, families, and communities about preventive healthcare.
This includes tasks like:
Administering vaccinations.
Providing education on nutrition, hygiene, and development.
Offering breastfeeding and childbirth support.
Counseling families on safety and injury prevention.
3. Collaboration and Advocacy:
Objective: Collaborate effectively with doctors, social workers, therapists, and other healthcare professionals to ensure coordinated care for children.
Objective: Advocate for the rights and best interests of their patients, especially when children cannot speak for themselves.
This includes tasks like:
Communicating effectively with healthcare teams.
Identifying and addressing potential risks to child welfare.
Educating families about their child's condition and treatment options.
4. Professional Development and Research:
Objective: Stay up-to-date on the latest advancements in pediatric healthcare through continuing education and research.
Objective: Contribute to improving the quality of care for children by participating in research initiatives.
This includes tasks like:
Attending workshops and conferences on pediatric nursing.
Participating in clinical trials related to child health.
Implementing evidence-based practices into their daily routines.
By fulfilling these objectives, pediatric nurses play a crucial role in ensuring the optimal health and well-being of children throughout all stages of their development.
Antibiotic Stewardship by Anushri Srivastava.pptxAnushriSrivastav
Stewardship is the act of taking good care of something.
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
WHO launched the Global Antimicrobial Resistance and Use Surveillance System (GLASS) in 2015 to fill knowledge gaps and inform strategies at all levels.
ACCORDING TO apic.org,
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
ACCORDING TO pewtrusts.org,
Antibiotic stewardship refers to efforts in doctors’ offices, hospitals, long term care facilities, and other health care settings to ensure that antibiotics are used only when necessary and appropriate
According to WHO,
Antimicrobial stewardship is a systematic approach to educate and support health care professionals to follow evidence-based guidelines for prescribing and administering antimicrobials
In 1996, John McGowan and Dale Gerding first applied the term antimicrobial stewardship, where they suggested a causal association between antimicrobial agent use and resistance. They also focused on the urgency of large-scale controlled trials of antimicrobial-use regulation employing sophisticated epidemiologic methods, molecular typing, and precise resistance mechanism analysis.
Antimicrobial Stewardship(AMS) refers to the optimal selection, dosing, and duration of antimicrobial treatment resulting in the best clinical outcome with minimal side effects to the patients and minimal impact on subsequent resistance.
According to the 2019 report, in the US, more than 2.8 million antibiotic-resistant infections occur each year, and more than 35000 people die. In addition to this, it also mentioned that 223,900 cases of Clostridoides difficile occurred in 2017, of which 12800 people died. The report did not include viruses or parasites
VISION
Being proactive
Supporting optimal animal and human health
Exploring ways to reduce overall use of antimicrobials
Using the drugs that prevent and treat disease by killing microscopic organisms in a responsible way
GOAL
to prevent the generation and spread of antimicrobial resistance (AMR). Doing so will preserve the effectiveness of these drugs in animals and humans for years to come.
being to preserve human and animal health and the effectiveness of antimicrobial medications.
to implement a multidisciplinary approach in assembling a stewardship team to include an infectious disease physician, a clinical pharmacist with infectious diseases training, infection preventionist, and a close collaboration with the staff in the clinical microbiology laboratory
to prevent antimicrobial overuse, misuse and abuse.
to minimize the developme
The dimensions of healthcare quality refer to various attributes or aspects that define the standard of healthcare services. These dimensions are used to evaluate, measure, and improve the quality of care provided to patients. A comprehensive understanding of these dimensions ensures that healthcare systems can address various aspects of patient care effectively and holistically. Dimensions of Healthcare Quality and Performance of care include the following; Appropriateness, Availability, Competence, Continuity, Effectiveness, Efficiency, Efficacy, Prevention, Respect and Care, Safety as well as Timeliness.
QA Paediatric dentistry department, Hospital Melaka 2020Azreen Aj
QA study - To improve the 6th monthly recall rate post-comprehensive dental treatment under general anaesthesia in paediatric dentistry department, Hospital Melaka
Welcome to Secret Tantric, London’s finest VIP Massage agency. Since we first opened our doors, we have provided the ultimate erotic massage experience to innumerable clients, each one searching for the very best sensual massage in London. We come by this reputation honestly with a dynamic team of the city’s most beautiful masseuses.
Telehealth Psychology Building Trust with Clients.pptxThe Harvest Clinic
Telehealth psychology is a digital approach that offers psychological services and mental health care to clients remotely, using technologies like video conferencing, phone calls, text messaging, and mobile apps for communication.
Navigating Challenges: Mental Health, Legislation, and the Prison System in B...Guillermo Rivera
This conference will delve into the intricate intersections between mental health, legal frameworks, and the prison system in Bolivia. It aims to provide a comprehensive overview of the current challenges faced by mental health professionals working within the legislative and correctional landscapes. Topics of discussion will include the prevalence and impact of mental health issues among the incarcerated population, the effectiveness of existing mental health policies and legislation, and potential reforms to enhance the mental health support system within prisons.
Leading the Way in Nephrology: Dr. David Greene's Work with Stem Cells for Ki...Dr. David Greene Arizona
As we watch Dr. Greene's continued efforts and research in Arizona, it's clear that stem cell therapy holds a promising key to unlocking new doors in the treatment of kidney disease. With each study and trial, we step closer to a world where kidney disease is no longer a life sentence but a treatable condition, thanks to pioneers like Dr. David Greene.
2. Contents
• Organs of GIT
• Function of the GIT
• Functional structures of GIT:
• Regulation of GIT
• Movement of GIT
• Secretions of GIT
3. Digestive System (GIT)
• The digestive system: processes
food, extracts nutrients and
eliminates wastes.
• It provide
• Nutrients
• Water and
• Electrolytes
- Four processes of GIT:
- Digestion: mechanical or
chemical
- Secretion: enzymes,
electrolytes (HCl,
NaHCO3), mucous, and
hormones
- Absorption: nutrients, water
& electrolytes
- Motility: propulsive or
mixing
Digestive organs
4. GIT and its natural defense
• GIT is hollow at both ends (mouth- to - Anus).
• Harbor microorganisms in its luminal surfaces.
• GI-system can protect itself by:
– Mouth: Saliva contains lysozymes, IgA etc.
– Stomach: HCl, Pepsin etc. have bactericidal effect
– SI (e.g., Payer's patches): Immuno-competent lymph tissues
– Macrophages: located in intestinal walls act to defend from
bacterial invasion etc.
5. GIT-organs and its accessories
1. Mouth
2. Pharynx
3. Esophagus
4. Stomach
5. SI
6. LI
7. Rectum
(Anus)
Main GI-Organs
Accessory Organs
1. Salivary
glands
2. Pancreas
3. Liver &
4. Gallbladder
Structure of the gut
The alimentary canal
that used to digests and
absorbs food
6. Layers of the GIT
1. Mucosa: protection, secretion
& absorption.
2. Submucosa: blood vessels,
glands, lymph, nerve plexuses
are found.
motility + secretion
3. Muscularis externa: Circular &
Longitudinal smooth muscle.
– mix and propel the chyme.
–
4. Serosa: outer most protective.
7. Regulation of GIT
Neural & Hormonal Regulation
A. Neural regulation of GI-activities: includes that of
a. Extrinsic (Autonomic N fibers)
b. Intrinsic (Enteric fibers)
Myenteric (Auerbach’s) plexus: (motility of the GIT)
Submucosa (Meissner’s) plexus: (secretions)
c. Somatic NS: voluntary
B. Hormonal regulation: Includes secretion of different hormones
like Gastrin, CCK, Secretin, GIP etc.
C. Paracrine Regulation:
-E.g.- Histamine (stimulates parietal cells to secrete HCl
-Somatostatin (inhibit secretion of gastrin by G-cells)
8. Receptors of the GI Tract
• Receptors initiate GI-reflexes that:
– Activate or inhibit GIT
• Mechanoreceptors:
~ respond to distension, spastic contraction
• Chemoreceptors:
~ respond to osmolarity, irritation, pH, presence of fat
and protein food and end products of digested food
• Thermoreceptors: respond to warm food/drinks
• Pain receptors: respond to tissue injury in the GIT.
9. Movements of the GIT
• Two basic types of movements
occur in the GIT:
1. Propulsive movements:
• cause food to move forward at an
appropriate rate for digestion and
absorption.
• Peristalsis: is propulsive
movement in the form of
contractile rings around the gut
and propels to the anal ward
direction.
Peristalsis and Segmentation
10. 2. Mixing movements :
• which keep the intestinal contents thoroughly mixed at all
times.
• Mixing contractions are beneficial to mix the food contents
with gastric juice (chyme).
11. Function of Saliva
a. Digestion: CHO-digestion begins in saliva .
• The enzyme ptyline breaks starch- to-maltose.
• Lingual lipase begins fat digestion in the mouth.
b. Protection: has anti-microbial actions (contains Lysozyme &
thiocyanate) that kills microbes.
c. Lubrication: Mucin found in saliva facilitates moistening
and swallowing of food, involved in speech.
d. Endocrine function: Sex steroids are found in saliva to
plasma levels.
12. Stomach
• Rugae ( a fold) increases SA.
• Function:
Storage up to 1.5L of food.
Mixing of food to form chyme.
Slow emptying the food into the SI at
a rate suitable for digestion and
absorption.
Secretary function: HCl, mucous,
pepsin, gastrin, IF
• Sterilization,
• Digestion: breakdown of proteins
begins.
• Absorption
• Facilitates defecation
14. Small Intestine
• Runs from pyloric sphincter
to the ileocecal valve
• Is site for completion of
digestion and absorption.
• Has three subdivisions:
• Duodenum, Jejunum,
Ileum
• The bile and pancreatic duct
join duodenum.
Digestive enzymes
Peptidase: splits peptides into AAs
2. Disaccharidase: sucrase, maltase
and lactase.
3. Intestinal lipase: splits neutral fats
into glycerol & FAs.
Regulation of SI secretion
• Local factors: tactile, distension,
irritation, PH.
• Hormonal: Secretin, CCK, VIP,
Glucagon, GIP
• Nervous: vagal and sympathetic
stimulation
• Enteric reflexes: stimulation of
submucosal plexus
15. Digestion in the Small Intestine
Carbohydrates
• Mouth: salivary amylase
• Oesophagus & stomach:
nothing happens
• Duodenum: pancreatic
amylase
• Brush border enzymes
(maltase, sucrase & lactase)
Digestion of Proteins
Stomach
• HCl denatures or unfolds
proteins
• Pepsinogen pepsin
• Pepsin proteins to
peptides
Pancreas
• split peptide to AA
SI
• Brush border enzymes
carboxypeptidases
aminopeptidases
dipeptidase
16. Dietary source of fat
• Triglycerides, Cholesterol, cholesterol esters and PL
Fat Emulsified fat FFA + Glycerides
-Lingual lipase
-Gastric lipase
-Pancreas lipase
Cholesterol Bile salt FFA + Glycerides
Cholesterol esters Cholesterol Esterase
Phospholipids-A2 Phospholipase FFA + Phospholipids
Digestion of Lipids
Bile salt
18. Large Intestine
Is subdivided into cecum, colon,
rectum, and anal canal
• The cecum: contains appendix
Colon has distinct regions:
ascending colon, transverse
colon, descending colon, and
sigmoid colon
• The sigmoid colon joins the
rectum
• The anal canal
19. Valves and Sphincters of the Rectum and Anus
Valves of the rectum stop feces from being passed with gas
• The anus has two sphincters:
– Internal anal sphincter composed of smooth muscle
– External anal sphincter composed of skeletal muscle
• Ileocecal valve (sphincter) : connects ileum -to- cecum. It is
mostly in a contracted state b/s:
a. Prevents bacterial penetration back to the SI.
b. It permits slow flow of chyme to the LI
20. Large intestine
• LI does not have villi, but has
goblet cells that secrete mucus.
Function of the large intestine
1. Absorption of drugs & water
2. Electrolyte (like NaCl) absorption
3. Mucous & HCO3
- secretion
4. Storage, transport, and evacuation
of feces
5. Bacterial fermentation in the
colon stimulates synthesis of
vitamins K.
• Movement in the LI
• Two types of movements
1. Mixing movements
(Haustration)
2. Propulsive movements
(mass movements)
• Mass movement :is initiated by
local distension, gastro-colic
reflex
* Poor motility: causes greater
absorption and constipation
* Excess motility: causes less
absorption and diarrhoea.
22. 22
Pancreas
• Pancreas contains two types of
secretary glands:
1. Endocrine cells (islets of
Langerhans)
* secrete hormones
2. Exocrine cells (acinar cells)
* secrete digestive enzymes called
pancreatic juice.
a. Digestive enzymes: necessary to
digest CHO, fat, and protein.
b. Bicarbonates : to neutralize the
gastric juice
c. Water and electrolytes (Na+, K+
etc.)
24. Liver and gallbladder
Liver
• Is the heaviest gland.
• Weighs 1.36kg.
• Located below diaphragm in
the abdomen
• The liver is divisible into left
and right lobes, separated by
the falciform ligament.
•
• Right lobe larger
• Gallbladder on right lobe
25. Functions of the liver
1. Metabolism:
CHO
glycogenesis, gluconeogenesis
and glycogenolysis
Lipid
β-oxidation, formation of PL, LP,
synthesis of cholesterol
Protein
• Deamination of AAs
• Converts ammonia (NH3) into
urea.
• Synthesizes plasma proteins
fibrinogen and gamma globulin.
2. Inactivation of drugs & hormones
3. Removes the waste product bilirubin
4. Releases bile salts
5. Stores: fat soluble vitamins, iron,
copper and blood reservoir
6. Filtration of blood:
• Old blood cells & bacteria.
• Removes blood clots and toxins
7. Activates vitamin D
8. Synthesis of clotting factors (F-I, II,
VII, IX, X)