The document summarizes the key stages and processes of digestion. It describes the functions of the main parts of the digestive system including the mouth, stomach, small intestine, liver, gallbladder and pancreas. It explains the mechanical and chemical breakdown of food as well as the roles of enzymes and hormones in digesting carbohydrates, proteins and fats. Absorption and motility in the small intestine is also summarized.
Bile is a bitter-tasting, dark green to yellowish brown fluid, produced by the liver , it is stored in the gallbladder and upon eating is discharged into the duodenum. .
The principal function of the gallbladder is to serve as a storage reservoir for bile.
The main components of bile are water, bile salts, bile pigments, and cholesterol
Bile salts act as emulsifying agents in the digestion and absorption of fats. Cholesterol and bile pigments from the breakdown of hemoglobin are excreted from the body in the bile.
Physical properties;
Hepatic bile: pH 7.4, colour is golden yellow ,
Bladder bile: pH 6.8, color is green dark to yellow (darker)
Volume of bile produced reaches to one liter of bile per day (depending on body size).
Bile is a bitter-tasting, dark green to yellowish brown fluid, produced by the liver , it is stored in the gallbladder and upon eating is discharged into the duodenum. .
The principal function of the gallbladder is to serve as a storage reservoir for bile.
The main components of bile are water, bile salts, bile pigments, and cholesterol
Bile salts act as emulsifying agents in the digestion and absorption of fats. Cholesterol and bile pigments from the breakdown of hemoglobin are excreted from the body in the bile.
Physical properties;
Hepatic bile: pH 7.4, colour is golden yellow ,
Bladder bile: pH 6.8, color is green dark to yellow (darker)
Volume of bile produced reaches to one liter of bile per day (depending on body size).
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
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
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Presentation is all about the Sexual Harassment on the women in the workplace and also talks about the law to protect women against these kind of inhuman activities.
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.
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
The digestive system is made up of the gastrointestinal tract—also called the GI tract or digestive tract—and the liver, pancreas, and gallbladder. The GI tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus.
Falcon stands out as a top-tier P2P Invoice Discounting platform in India, bridging esteemed blue-chip companies and eager investors. Our goal is to transform the investment landscape in India by establishing a comprehensive destination for borrowers and investors with diverse profiles and needs, all while minimizing risk. What sets Falcon apart is the elimination of intermediaries such as commercial banks and depository institutions, allowing investors to enjoy higher yields.
Cracking the Workplace Discipline Code Main.pptxWorkforce Group
Cultivating and maintaining discipline within teams is a critical differentiator for successful organisations.
Forward-thinking leaders and business managers understand the impact that discipline has on organisational success. A disciplined workforce operates with clarity, focus, and a shared understanding of expectations, ultimately driving better results, optimising productivity, and facilitating seamless collaboration.
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Sustainability has become an increasingly critical topic as the world recognizes the need to protect our planet and its resources for future generations. Sustainability means meeting our current needs without compromising the ability of future generations to meet theirs. It involves long-term planning and consideration of the consequences of our actions. The goal is to create strategies that ensure the long-term viability of People, Planet, and Profit.
Leading companies such as Nike, Toyota, and Siemens are prioritizing sustainable innovation in their business models, setting an example for others to follow. In this Sustainability training presentation, you will learn key concepts, principles, and practices of sustainability applicable across industries. This training aims to create awareness and educate employees, senior executives, consultants, and other key stakeholders, including investors, policymakers, and supply chain partners, on the importance and implementation of sustainability.
LEARNING OBJECTIVES
1. Develop a comprehensive understanding of the fundamental principles and concepts that form the foundation of sustainability within corporate environments.
2. Explore the sustainability implementation model, focusing on effective measures and reporting strategies to track and communicate sustainability efforts.
3. Identify and define best practices and critical success factors essential for achieving sustainability goals within organizations.
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1. Introduction and Key Concepts of Sustainability
2. Principles and Practices of Sustainability
3. Measures and Reporting in Sustainability
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To download the complete presentation, visit: https://www.oeconsulting.com.sg/training-presentations
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4. Digestive Functions & Processes
• Functions
– ingestion = intake of food
– digestion = breakdown of molecules
– absorption = uptake of nutrients into blood or lymph
– defecation = elimination of undigested material
• Processes
– motility = muscular contractions that break up food,
mix it with enzymes & move it along
– secretion = digestive enzymes & hormones
– membrane transport = absorption of nutrients
5. Stages of Digestion
• Mechanical digestion is physical breakdown of food into smaller
particles
– teeth & churning action of stomach & intestines
• Chemical digestion is series of hydrolysis reactions that break
macromolecules into their monomers
– enzymes from saliva, stomach, pancreas & intestines
– results
• polysaccharides into monosaccharides
• proteins into amino acids
• fats into glycerol and fatty acids
6. Saliva
• Functions of saliva
– moisten, begin starch & fat digestion, cleanse teeth, inhibit
bacteria, bind food together into bolus
• Hypotonic solutions of 99.5% water and solutes:
– amylase = begins starch digestion
– lingual lipase = digests fat after reaches the stomach
– mucus = aids in swallowing
– lysozyme = enzyme that kills bacteria
– immunoglobulin A = inhibits bacterial growth
– electrolytes = Na+, K+, Cl-, phosphate & bicarbonate
• pH of 6.8 to 7.0
9. The esophagus
Saliva contains salivary amylase. It hydrolyzes the glucose polymers starch and glycogen. The
epiglottis blocks the top of the windpipe when we swallow. Peristalsis moves the bolus along the
epiglottis.
10. The stomach
The stomach can hold 2L of food and water. The lining of the stomach secretes gastric acid.
Gastric acid contains HCl and pepsin. Pepsin is an enzyme that hydrolyzes proteins. But it breaks
proteins into smaller polypeptides.
11. Functions of Hydrochloric Acid
• Activates enzymes pepsin & lingual lipase
• Breaks up connective tissues & plant cell
walls
– liquifying food to form chyme
• Converts ingested ferric ions (Fe+3) to
ferrous ions (Fe+2) that can be absorbed &
utilized for hemoglobin synthesis
• Destroys ingested bacteria & pathogens
12. Small Intestine
• Nearly all chemical digestion and nutrient absorption
occurs in the small intestine
15. The digestive enzymes in the table below are summarized
according to type of food that they digest.
FOOD TYPE
ENZYME SOURCE PRODUCTS
CARBOHYDRATES Salivary amylase
Pancreatic amylase
Maltase
Salivary glands
Pancreas
Small intestine
Maltose
Maltose
Glucose
PROTEINS Pepsin
Trypsin
Peptidases
Stomach mucosa
Pancreas
Intestinal mucosa
Peptides
Peptides
Amino acids
FATS Lipase Pancreas Fatty acids
and glycerol
16. The table below shows digestive enzymes grouped by source of the enzyme.
SOURCE
ENZYME FOOD PRODUCT
MOUTH (salivary glands) Salivary amylase Polysaccharides Maltose
STOMACH Pepsin Proteins Peptides
PANCREAS Pancreatic amylase
Trypsin
Lipase
Polysaccharides
Proteins
Fats
Maltose
Peptides
Fatty acids
and glycerol
SMALL INTESTINE Maltase
Peptidases
Maltose
Peptides
Glucose
Amino acids
17. • Digestive function is affected by hormones produced in many
endocrine glands, but the most profound control is exerted by
hormones produced within the gastrointestinal tract. The
gastrointestinal tract is the largest endocrine organ in the
body and the endocrine cells within it are referred to
collectively as the enteric endocrine system. Three of the best-
studied enteric hormones are:
• Gastrin: Secreted from the stomach and plays an important
role in control of gastric acid secretion.
• Cholecystokinin: A small intestinal hormone that stimulates
secretion of pancreatic enzymes and bile.
• Secretin: Another hormone secreted from small intestinal
epithelial cells; stimulates secretion of a bicarbonate-rich
fluids from the pancreas and liver.
18. HORMON
ES
Major Activities Stimuli for Release
Gastrin
Stimulates gastric acid secretion and proliferation of gastric
epithelium
Presence of peptides and amino acids in gastric lumen
Cholecyst
okin
in
Stimulates secretion of pancreatic enzymes, and contraction and
emptying of the gall bladder
Presence of fatty acids and amino acids in the small
intestine
Secretin
Stimulates secretion of water and bicarbonate from the pancreas
and bile ducts
Acidic pH in the lumen of the small intestine
Ghrelin
Appears to be a strong stimulant for appetite and feeding; also a
potent stimulator of growth hormone secretion.
Not clear, but secretion peaks prior to feeding and
diminishes with gastric filling
Motilin
Apparently involved in stimulating housekeeping patterns of motility
in the stomach and small intestine
Not clear, but secretion is associated with fasting
Gastric
inhi
bitor
y
poly
pept
ide
Inhibits gastric secretion and motility and potentiates release of
insulin from beta cells in response to elevated blood glucose
concentration
Presence of fat and glucose in the small intestine
19. Hormones and Digestion:Feedback loops.The hormone Gastrin stimulates the production of
gastric acid.The pyloric sphincter regulates the release of chyme (nutrient broth) into the small
intestine.Bile contains bile salts that aid digestion and absorption of fats.
20. • Secretin hormone production is stimulated by acid
chyme entering the duodenum. This hormone
stimulates the pancreas to release bicarbonate to
neutralize the acid.
• CCK stimulates the gall bladder to release bile and
the panceas to release pancreatic juices.
• If the chyme is rich in fats causes the release of
enterogastrone. This hormone inhibits peristalsis
and the release of secretion of acid.
23. Essential Amino Acids
• The human liver can synthesize 9 of the 20 amino acids used
in proteins. Those that cannot be synthesized are called the
essential amino acids. They must be supplied by diet.
24. Bile Ducts and Gallbladder
Definition:
Bile is produced by the liver cells and collects in the small bile ducts between the
microscopic liver lobules which lead to the larger ducts. Outside the liver, two
outflowing hepatic ducts unite to form the common hepatic duct. From here the bile
enters the cystic duct and the common bile duct . The common bile duct joins the
pancreatic duct to enter the duodenum. The opening is controlled by a valve which
regulates the flow of gastric juices (bile, pancreatic enzymes) into the duodenum.
25. • Function:
Bile is produced in the liver and aids the digestion of fatty
food substances. Between 250 and 1000 millilitres of bile are
produced each day. The most important constituents of bile
are: water, bile salts, cholesterol , phospholipids . Between
meals, the bile is stored in the gallbladder, which contracts
once or twice as food is taken. This causes the bile to enter
the duodenum via the common bile duct. 80 to 90% of the
bile acids are later reabsorbed by the small intestine and re-
enter the liver via the bloodstream (portal system).
27. Absorption and Motility
• Transit time is 12 to 24 hours
– reabsorbs water and electrolytes
• Feces consist of water & solids (bacteria, mucus, undigested fiber, fat &
sloughed epithelial cells
• Haustral contractions occur every 30 minutes
– distension of a haustrum stimulates it to contract
• Mass movements occur 1 to 3 times a day
– triggered by gastrocolic and duodenocolic reflexes
• filling of the stomach & duodenum stimulates motility
• moves residue for several centimeters with each contraction
28. Defecation
• Stretching of the rectum stimulates defecation
– intrinsic defecation reflex via the myenteric plexus
• causes muscularis to contract & internal sphincter to relax
– relatively weak contractions
• defecation occurs only if external anal sphincter is voluntarily relaxed
– parasympathetic defecation reflex involves spinal cord
• stretching of rectum sends sensory signals to spinal cord
• splanchnic nerves return signals intensifying peristalsis
• Abdominal contractions increase abdominal pressure as levator ani lifts anal
canal upwards
– feces will fall away
