Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
136 Cards in this Set
- Front
- Back
|
What are the 5 main stages of digestion? |
Ingestion Propulsion (mixes and moves) Digestion (mechanical breakdown & chemical digestion) Absorption (pass through walls of some organs into blood and Lymph capillaries) Elimination (defaecation) |
|
|
What's included in the alimentary canal? |
Mouth Pharynx Oesophagus Stomach Small intestine Large intestine Rectum & anal canal |
|
|
What are the accessory organs? |
Salivary glands (3) Pancreas Liver Biliary tract |
|
|
Walls of the alimentary tract are formed by 4 layers. What are they? |
Adventitia/serosa (outer) Muscle layer Submucosa Mucosa (lining) |
|
|
What tissue is the adventitia serosa made out of ? |
Loose fibrous tissue |
|
|
Where would you find the largest adventitia/serosa? What's it called?
|
The abdomen
The peritoneum |
|
|
What is the peritoneum? |
closed sac containing small amount of serous fluid secreted by the peritoneal cells |
|
|
The alimentary tract - consist of 2 muscle layers - what type of muscle are they made from? |
Smooth (in-voluntary)*allows bowel to move*
Outer and inner |
|
|
What fibres are the 2 layers made from? |
Outer - longitudinal
Inner - circular |
|
|
What would u find between the 2 layers? |
Blood vessels Lymph vessels Plexus or sympathetic/parasympathetic nerves |
|
|
What is peristalsis? |
"Wave like contraction and relaxation of muscle layer"
Onward movement Controlled by sphincters Autonomic nervous system Helps mix food with digestive juices |
|
|
What tissue is the sub mucosa made from? |
Loose connective with some elastic fibres *strongest layer in the tube* |
|
|
What does the sub mucosa contain? |
Blood vessels (Arterioles, venules, capillaries) Nerves Lymph vessels and lymphoid tissue Nerve plexus Sympathetic and parasympathetic nerves |
|
|
The mucosa consists of 3 layer, what are they? And what is its function? |
Function: specialised for absorption and secretion
Mucous membrane - protection, absorption, excretion
Lamina propria - loose connective tissue that supports the epithelial layer and had some lymph tissue
Muscular is mucosa - smooth muscle, provides involutions of the mucosa later eg. Gastric glands and villi |
|
|
What is the mucous membrane lined with? - subject to friction/ not subject to friction? |
Subject to friction Stratified squamous epithelium with mucous secreting glands
Less subject to friction Columnar epithelium cells interspersed with mucous secreting goblet cells |
|
|
The mouth.
What tissue is it lined with and what is its function? |
Stratified squamous epithelium containing small mucous secreting glands
Function Mechanical digestion - mastication Formation of bolus |
|
|
Pharynx consists of 3 parts, can you name them, and what are their functions? |
Nasopharynx Oropharynx Laryngopharynx
* all lined with Stratified squamous epithelium*
Functions- Respiration |
|
|
Oesophagus
What tissue is it lined with? upper lower outer covering |
upper - stratified squamous epithelium
lower - columnar epithelium
outer covering - elastic fibrous tissue |
|
|
What's the function of the upper and lower sphincter in the Oesophagus? |
Upper - prevents air passing into Oesophagus and aspiration of oesophageal contents
Lower - prevents acid reflux |
|
|
The stomach
What does it connect? |
Oesophagus to the small intestine |
|
|
The stomach has 3 regions, what are they? |
Fundus Body Antrum |
|
|
The stomach has 3 muscle layers, what fibres are they made from?
Outer Middle Inner |
Outer - longitudinal Middle - circular Inner - oblique |
|
|
What is the function of the stomach? |
-Mechanical breakdown
-Chemical breakdown
-Temp food reservoir
-Non specific defence against microbes
-Production of intrinsic factor
-Prep of iron for absorption
-Limited absorption of water, alcohol, some lipid soluble drugs |
|
|
What does gastric juice contain? |
Water Hydrochloric acid Intrinsic factor Mucous |
|
|
What is chyme? |
Churning motion Breaks down bolus Mixes with gastric juice |
|
|
What's the functions of:
Water Hydrochloric acid Intrinsic factor Mucous |
Water - liquifies swallowed food
Hydrochloric acid - acidified food, stops salivary amylase, kills ingested microbes, activates and stimulates pepsinogens
Intrinsic factor - B12 from ileum
Mucous - lubricates contents Prevents mechanical and chemical injury |
|
|
The stomach is divided into 3 sections. What are they? |
Duodenum (25cm) Jejunum (2m) Ileum (3m) |
|
|
Small intestine contains villi and micro villi, what are they lined with? |
Villi - columnar epithelial cells
Enterocytes Capillaries Lacteals Goblet cells Intestinal gland
Micro villi - columnar epithelial cells |
|
|
What's the function of small intestine? |
Secretion
Absorption
Chemical digestion of:
Carbohydrates - monosaccharides Proteins - amino acids Fats - fatty acids and glycerol |
|
|
What is lacteal? |
Absorbed fat - gives lymph a milky appearance |
|
|
What does a goblet cell do? |
Secreted mucous |
|
|
Function of intestinal glands? |
chemical digestion of carbs, proteins, and fats
Hormones - secretin and cholecystokinin (CCK) |
|
|
How much intestinal juice is secreted daily? |
1.5 litres |
|
|
What does intestinal juice contain? |
Water Mucous Mineral salts Enterokinase Enterocytes |
|
|
What's the function of IJ? |
Chemical breakdown
Breakdown peptides into amino acids and fats into fatty acids |
|
|
What is Enterokinase? |
A enzyme that starts the activation of proteolytic enzymes that break down polypeptides
Peptides break down to amino acids inside enterocytes |
|
|
What do enterocytes contain? |
Peptidases Lipase Sucrase, maltase, lactase
|
|
|
What happens in enterocytes? |
Fats broken down to fatty acids
Glycerol partly in intestine and partly in enterocytes
Disaccharides are broken down to monosaccharides within the enterocytes |
|
|
The large intestine has 5 sections, what are they? |
Caecum Ascending colon Transverse colon Descending colon Sigmoid colon |
|
|
How many layers does the large intestine have? |
4
(More lymphoid tissue in the submucosal layer) |
|
|
What's the function of large intestine? |
Absorption - mainly water and salts, semisolid faeces
Commensals bacteria- synthesis Vit K and folic acid
Mass movement - twice an hour a wave of peristalsis travels along transverse colon forcing the contents onward
Defaecation - mass movement forces contents of sigmoid colon into the rectum |
|
|
What is the function of the liver? |
Metabolism (carb, protein and fat)
Secretion of bile
Detoxification of drugs and alcohol
Inactivation of hormones
Breakdown of RBC |
|
|
What is the function of the liver? |
Metabolism (carb, protein and fat)
Secretion of bile
Detoxification of drugs and alcohol
Inactivation of hormones
Breakdown of RBC |
|
|
How much bile is secreted daily? |
1 litre
(Stored in gall bladder) |
|
|
What is the function of the liver? |
Metabolism (carb, protein and fat)
Secretion of bile
Detoxification of drugs and alcohol
Inactivation of hormones
Breakdown of RBC |
|
|
How much bile is secreted daily? |
1 litre (Stored in gall bladder) |
|
|
What does bile contain? |
Water Mineral salts Mucous Bile salts and pigments |
|
|
What is the function of the liver? |
Metabolism (carb, protein and fat)
Secretion of bile
Detoxification of drugs and alcohol
Inactivation of hormones
Breakdown of RBC |
|
|
How much bile is secreted daily? |
1 litre (Stored in gall bladder) |
|
|
What does bile contain? |
Water Mineral salts Mucous Bile salts and pigments |
|
|
What is bilirubin? |
A waste products of when RBC are broken down. |
|
|
What is the function of the liver? |
Metabolism (carb, protein and fat)
Secretion of bile
Detoxification of drugs and alcohol
Inactivation of hormones
Breakdown of RBC |
|
|
How much bile is secreted daily? |
1 litre (Stored in gall bladder) |
|
|
What does bile contain? |
Water Mineral salts Mucous Bile salts and pigments |
|
|
What is bilirubin? |
A waste products of when RBC are broken down in the liver and excreted in bile. Yellow/orange pigment. |
|
|
What's the function of bile? |
Emulsifying fats
Excretion if bilirubin
Improve solubility of fatty acids |
|
What is the function of a gall bladder? |
Reservoir of bile Concentrates bile Releases bile |
|
|
How many litres does saliva secrete daily? |
1.5 litre |
|
What is the gall bladder? |
Reservoir of bile Concentrates bile Releases bile |
|
|
How many litres does saliva secrete daily? |
1.5 litre |
|
|
What's the function of saliva? |
Chemical digestion - salivary amalayse. Breakdown of complex carbs.
Bolus formation
Lubrication - prevents damage
Anti microbial - lysozyme and immunoglobulins
Buffering - neutralise ph
Taste
Blood clotting factors response to trauma
|
|
What is the exocrine pancreas? |
Lobules with secretory ducts
Lobule drained by duct and united to form pancreatic duct
Duct opens into duodenum
Just before duct joins with bile duct - creates pancreatic juice (contains enzymes that digest - carbs, proteins and fats) |
|
|
What's the endocrine pancreas? |
Secretes hormones that circulate within the body via the blood stream
-Special cells -Islets of langer hand -No ducts -Production of insulin and glucagon -blood, nutrient and glucose regulation |
|
**What is the function and structure of the exocrine pancreas?** |
-Large number of Lobules (made up of small acini) walls consist of secretory cells
-Each is Lobule drained by tiny ducts and untied to form pancreatic duct
-Extends the whole length of the gland and opens into duodenum
- Just before- the duct joins with common bile duct to form hepatopancreatic ampulla. The duodenal opening of the ampulla is controlled by the hepatopancreatic sphincter at the duodenal papilla.
Function: creates pancreatic juice which contains enzyme rich secretion that digest - carbs, proteins and fats
|
|
|
**What's the endocrine pancreas?** |
Distributed throughout the gland are groups of specialised cells called the pancreatic islets (of langerhans)
Ilet's have no ducts so the hormones diffuse directly into the blood.
Secretes hormones that circulate within the body via the blood stream
Function Production of insulin and glucagon
blood, nutrient and glucose regulation |
|
|
What's the ph of pancreatic juice? |
8 |
|
|
What does PJ contain? |
Water
Mineral salts
Enzyme (amylase/lipase)
Inactive enzyme precursors (Trysinogen/ chymotrypsinogen) |
|
|
What's the nerve supply to the GI system? |
Autonomic
Sympathetic and parasympathetic |
|
|
What's the nerve supply to the GI system? |
Autonomic
Sympathetic and parasympathetic |
|
|
What does the sympathetic nerve supply do to the GI system? |
Decreases digestive activity
Reduce smooth muscle contraction and decrease secretions |
|
|
What's the nerve supply to the GI system? |
Autonomic
Sympathetic and parasympathetic |
|
|
What does the sympathetic nerve supply do to the GI system? |
Decreases digestive activity
Reduce smooth muscle contraction and decrease secretions |
|
|
What does the parasympathetic system do to the GI system? |
Increases digestive activity
Stimulates smooth muscle contraction and secretion of digestive juices |
|
|
Where are carbs digested and absorbed? |
Mouth salivary amalayse
Stomach Hydrochloric acid
Small intestine Digestion - pancreatic amylase Absorption- blood capillaries |
|
|
Where are carbs digested and absorbed? |
Mouth salivary amalayse
Stomach Hydrochloric acid
Small intestine Digestion - pancreatic amylase
Absorption- blood capillaries |
|
|
Where are proteins digested and absorbed? |
Stomach Hydrochloric acid (pepsin)
Small intestines Pancreas - Enterokinase, chymotrypsin, trypsin
Absorption- blood capillaries of villi |
|
|
Where are carbs digested and absorbed? |
Mouth salivary amalayse
Stomach Hydrochloric acid
Small intestine Digestion - pancreatic amylase
Absorption- blood capillaries of villi |
|
|
Where are carbs digested and absorbed? |
Mouth salivary amalayse
Stomach Hydrochloric acid
Small intestine Digestion - pancreatic amylase
Absorption- blood capillaries of villi |
|
|
Where are fats digested and absorbed? |
Small intestine Bile - bile salts emulsify fats Pancreatic lipase - fats to fatty acids Lipases - fats to fatty acids and glycerol
Absorption - lacteals of villi |
|
|
Where are carbs digested and absorbed? |
Mouth salivary amalayse
Stomach Hydrochloric acid
Small intestine Digestion - pancreatic amylase
Absorption- blood capillaries of villi |
|
|
Where are fats digested and absorbed? |
Small intestine Bile - bile salts emulsify fats Pancreatic lipase - fats to fatty acids Lipases - fats to fatty acids and glycerol
Absorption - lacteals of villi |
|
|
Where is water digested and absorbed? |
Stomach - small amount
Small intestine - most here
Large intestine - remainder |
|
|
Where are carbs digested and absorbed? |
Mouth salivary amalayse
Stomach Hydrochloric acid
Small intestine Digestion - pancreatic amylase
Absorption- blood capillaries of villi |
|
|
Where are fats digested and absorbed? |
Small intestine Bile - bile salts emulsify fats Pancreatic lipase - fats to fatty acids Lipases - fats to fatty acids and glycerol
Absorption - lacteals of villi |
|
|
Where is water digested and absorbed? |
Stomach - small amount
Small intestine - most here
Large intestine - remainder |
|
|
Where are vitamins digested and absorbed? |
Stomach Intrinsic factor secreted for Vit B12 absorption
Small intestine Absorption - water soluble vita absorbed into capillaries Fat soluble into lacteal of villi
Large intestine Bacteria synthesis of Vit K in colon |
|
|
****Principles of metabolism**** |
Constituent of all chemical reactions that occur in the body
- provide energy by chemical oxidation of nutrients - make new or replacement body substances - 2 processes (catabolism and anabolism) |
|
|
****Principles of metabolism**** |
Constituent of all chemical reactions that occur in the body
- provide energy by chemical oxidation of nutrients - make new or replacement body substances - 2 processes (catabolism and anabolism) |
|
|
What is catabolism? |
Breakdown of large molecules Into smaller ones.
Releasing chemical energy, which is stored as ATP and heat.
Heat is used to maintain core body temperature at the optimum level for chemical activity (36.8 degrees) excess heat is lost through the skin. |
|
|
What's is anabolism? |
Small molecules to larger molecules
Needs a source of energy (usually ATP) |
|
|
What's is anabolism? |
Small molecules to larger molecules
Needs a source of energy (usually ATP) |
|
|
Anabolism and catabolism are involved in a series of chemical reactions to produce energy, what is this called? |
metabolic pathways
These consist of small steps that permit gradual transfer of energy from ATP rather than intracellular explosions |
|
|
What's is anabolism? |
Small molecules to larger molecules
Needs a source of energy (usually ATP) |
|
|
Anabolism and catabolism are involved in a series of chemical reactions to produce energy, what is this called? |
metabolic pathways
These consist of small steps that permit gradual transfer of energy from ATP rather than intracellular explosions |
|
|
What are metabolic pathways controlled by? |
Hormones - switch on and off meeting individual requirements.
Both occur continually in all cells maintaining energy balance. |
|
|
How is energy produced in the body measured? |
Units of work (joules) Units of heat (Kilocalories) |
|
|
How is energy produced in the body measured? |
Units of work (joules) Units of heat (Kilocalories) |
|
|
On a daily basis, how many kilocalories does the body collective metabolic process generate? |
3.3 million kilo calories |
|
|
What is metabolic rate? |
The rate the energy is released from the fuel molecules inside cells. Involved oxygen and carbon dioxide. |
|
|
What is metabolic rate? |
The rate the energy is released from the fuel molecules inside cells. Involved oxygen and carbon dioxide. |
|
|
What is BMR? |
Basal Metabolic Rate.
Rate of metabolism when the individual is at rest in a warm environment and is in a postabsorptive state. (Not had a meal for 12 hours) |
|
|
What are the 3 central metabolic pathways? |
Glycolysis (first stage of glucose catabolism)
Citric acid (krebs) cycle
Oxidative phosphorylation |
|
|
What are the end products of carbohydrate metabolism? |
Lactic acid - produced by anaerobic catabolism of glucose
Carbon dioxide - excreted from the body as a gas by the lungs
Metabolic water - added to water of the body, excess is excreted in urine |
|
|
What elements are carbohydrates a mix of? |
Carbon
Hydrogen
Oxygen |
|
|
Name the different types of carbohydrates and what do they turn into? |
Monosaccharide Glucose Fructose Galactose
Disaccharide Maltose Sucrose Lactose
Polysaccharide Starch Glycogen Cellulose |
|
|
Name the different types of carbohydrates and what do they turn into? |
Monosaccharide Glucose Fructose Galactose
Disaccharide Maltose Sucrose Lactose
Polysaccharide Starch Glycogen Cellulose |
|
|
What's the function of carbohydrates? |
Heat and energy
Protein sparing
Energy store (glycogen liver and skeletal muscle fat) |
|
|
What is the mix of elements for protein? |
Carbon
Hydrogen
Oxygen
Nitrogen |
|
|
What's the enzyme involved in synthesis of amino acids are know as..? |
Transaminases |
|
|
Name 2 sources of amino acids? |
Exogenous - derived from dietary protein
Endogenous - obtained from the breakdown of body proteins |
|
|
How many amino acids have been named and how many are described as essential? |
20 named
9 essential (cannot be synthesised by the body)
11 (can be synthesised by many tissues) |
|
|
Proteins are a source of nitrogen, true or false? |
True |
|
|
Proteins are a source of nitrogen, true or false? |
True |
|
|
What's the function of proteins? |
Buffering effect of acids
Growth and repair of cells and tissue
Synthesis of enzymes, plasma proteins, anti-bodies, some hormones
Source of energy if carbohydrates and fat stores are depleted |
|
|
Where are amino acids broken down? |
Liver.
Converted into ammonia then combined with carbon dioxide forming urea. |
|
|
When are amino acids used? |
Only when the other energy sources are low eg. In starvation |
|
|
List 9 essential amino acids |
Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine |
|
|
List 9 essential amino acids |
Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine |
|
|
What do fats consist of? |
Carbon
Hydrogen
Oxygen |
|
|
Which fats are essential in the diet? |
Poly-unsaturated |
|
|
Which fats are essential in the diet? |
Poly-unsaturated |
|
|
List the types of fats |
Saturated (animal fat) Cholesterol (synthesises/ diet) Unsaturated (vegetable fat) Linoleic and arachidonic acids |
|
|
Which fats are essential in the diet? |
Poly-unsaturated |
|
|
List the types of fats |
Saturated (animal fat) Cholesterol (synthesises/ diet) Unsaturated (vegetable fat) Linoleic and arachidonic acids |
|
|
Functions of fat |
Transport and storage of fat soluble vitamins: A, D, E, K
Energy store/ source
Constituents to nerve sheaths
Satiation - delays return of hunger
Support of body organs (surrounds kidneys)
Insolation |
|
|
Which fats are essential in the diet? |
Poly-unsaturated |
|
|
List the types of fats |
Saturated (animal fat) Cholesterol (synthesises/ diet) Unsaturated (vegetable fat) Linoleic and arachidonic acids |
|
|
Functions of fat |
Transport and storage of fat soluble vitamins: A, D, E, K
Energy store/ source
Constituents to nerve sheaths
Satiation - delays return of hunger
Support of body organs (surrounds kidneys)
Insolation |
|
|
fat lining the eyeball helps you see in the dark? True or false? |
True |
|
|
Where would you find fat soluble vitamin A and what are the benefits? |
Food: Cream, eggs yolk, liver, fish oil, milk, cheese, butter, green veg, fruits and carrots.
Benefits: -rods in retina (retinol) -cell growth and differentiation -promotion of immunity - promotion of growth |
|
|
Which fats are essential in the diet? |
Poly-unsaturated |
|
|
List the types of fats |
Saturated (animal fat) Cholesterol (synthesises/ diet) Unsaturated (vegetable fat) Linoleic and arachidonic acids |
|
|
Functions of fat |
Transport and storage of fat soluble vitamins: A, D, E, K
Energy store/ source
Constituents to nerve sheaths
Satiation - delays return of hunger
Support of body organs (surrounds kidneys)
Insolation |
|
|
fat lining the eyeball helps you see in the dark? True or false? |
True |
|
|
Where would you find fat soluble vitamin A and what are the benefits? |
Food: Cream, eggs yolk, liver, fish oil, milk, cheese, butter, green veg, fruits and carrots.
Benefits: -rods in retina (retinol) -cell growth and differentiation -promotion of immunity - promotion of growth |
|
|
Where would you find fat soluble vitamin D and what are the benefits? |
Food: Animal fats, eggs, butter, cheese, fish liver oil.
Environment: Sunlight (UV Ray)
Benefits: Regulates calcium and phosphate metabolism, increases absorption from gut stimulating retention by the kidneys.
Promotes calcification of bones and teeth.
Deficiency: Rickets (children) Osteomalacia (adults) |
