Chapter 7- Monogastrics Flashcards
Where do you find lactose?
Dairy products
Name simple carb sugars:
-Monosaccharides(glusose, fructose, galactose)
-Disaccharides(maltose, lactose, surcose)
Name complex carbs:
-Polysaccharides (Starches, Fibers, Glycogen)
Polysaccharide examples :
(Starches, Fibers, Glycogen)
Disaccharides examples
(maltose, lactose, surcose)
Monosaccharides examples
(glusose, fructose, galactose)
Whats carbs made up of?
- CHO are made of:
– Carbon
– Hydrogen
– Oxygen - Hence the acronym (CHO)
- H to O ration as in water (2:1)
Whats the most abundant class of bioorganic molecules on earth (10^15kg synthesized annually)
Carbohydrates
What does carbs accumulate as a result of
Photosynthesis
Sugar formula
C6H12O6
Whats the function of carbs in animals diet?
– CHO are not an essential nutrient
* Glucose is too important to leave it up to dietary choice
* Can synthesize glucose from carbon precursors (gluconeogenesis)
Whats the major component of plant tissues?
Carbohydrates
Comprise up to 70% or more of dry matter of forages
Make up less than 1% of the weight of animals
Whats the same as starch?
carbohydrate
What are carbs made up of molecules called?
Sugars (saccharides)
Whats saccharides classified by ?
- Classified according to the number
of monomeric (sugar) molecules: - Monosaccharides - 1 unit
- Disaccharides - 2 units
- Oligosaccharides - 3 to 10 units
- Polysaccharides - Greater than 10
units - Most plants contain different types of
carbohydrates than animals
Whats the formula for monosaccharides :
CnH2nOn
How are monosaccharides classified by ?
the number of carbon atoms
– 3-C =triose
– 4-C =tetrose
– 5-C =pentose
– 6-C =hexose
nutritionally important
Sugars that contain four or more carbons exist primarily in cyclic form
Where is the sugar that contains for or more carbon exist
Primarily in cyclic form
What is the primary source of toast ?
Sugar
Name the 2 simple sugars: (monosaccharides)
-Pentoses
-Hexoses
List Pentoses (monosaccharides with 5 carbons)
– Arabinose
– Xylose
– Ribose
List hexoses (monosaccharides with 6 carbons)
– Glucose
– Fructose
– Galactose
– Mannose
Where is glucose found in? what type of foods?
Fruits, veg, honey “blood sugar”- used for energy
Where is fructose found in , what foods?
“fruit sugar”- found in fruits, honey, corn syrup
Where is galactose found in? what food?
Part of lactose in milk
Name the basic unit of a polysaccharide
Glucose
What do all 3 monosaccharides have?
-6 carbons,
-12 hydrogens,
-6 oxygens.
What’s the only difference between Glucose and Galactose ?
the location of the H and OH
Where is galactose found?
Component of milk sugar (lactose)
May be metabolised to glucose
Its found as part of lactose in milk
Where is fructose found?
75% of the sugars in honey
Found in fruits and cane sugar
Its found in fruits, vegetables and honey
In fructose, each of these molecules can exist in two forms (mirror images) what are they called?
D or L optical isomers.
The body can only use one of these forms, the D isomer.
Name the 3 monosaccharides:
Glucose
Galactose
Fructose
Why is it sometimes difficult to tell glucose and galactose apart?
Because they share similar 6-sided hexagonal structures, they can be difficult to tell apart. Fructose 5-sided pentagon stands out.
What are blue jeans made up of?
Carbohydrates, cotton is a carbohydrates
List monosaccharides that have hexoses (6c)
-Fructose
-Galactose
-Mannose
What are the vast majority of plants and fruits made up of?
-Sugars
What is Mannose formed after?
Hydrolysis of plant structural CHO
List the monosaccharide that have a Pentoses (5c)
-Xylose and Arabinose
-Ribose
What is arabinose and xylose a component of? (Monosaccharides)
Its a component of hemicellulose and glycoproteins
Saccharide formulation:
C6 H12 O6
What is Ribose found in and what are compounds involved in?
Found in every living cell
Found in compounds involved in metabolism
-ATP/ADP
-Riboflavin
-Key component of DNA/RNA
What are disaccharides?
Two linked sugar units
Name disaccharides (3)
-Sucrose
-Lactose
-Maltose
Name how Sucrose is formed and what are they made up of?
Glucose + Fructose - Glucose and fructose “table sugar” made from sugar cane and sugar beets
Name how lactose is formed and what are they made up of?
glucose + galactose
* “milk sugar”
* Found in milk and dairy products
When 2 sugars are bound together the bond that connects them is a…
Glyosidic bond
Name how glucose is made up? what is it the product of?
glucose + glucose
* Found in germinating cereal grains
* Product of starch breakdown
What bond connects 2 sugars?
Glyosidic bond
What can a glyosidic bond be either?
- a configuration
- b configuration
It can be linked through the 1-2, 1-4, 1-6 linkage
What can our body only absorb?
Monosaccharides (down to its simplest form)
Definition of Disaccharides
2 monosaccharide molecules linked by a glyosidic bond
Name 3 disaccharides?
-Lactose
-Maltose
-Sucrose
Whats the only enzymes that can break down cellulose?
Only thing that can break down the beta 1-4 linkage is the microorganims in your large intestine
Whats maltose a product of?
Starch hydrolysis
What is a glyosidic bond definition :
A covalent bond binding a carbohydrate molecule to another
What are complex carbohydrates?
-List them
Chains of more than two sugar molecules,
-Oligosaccharides
-Polysaccharides
-Starch
-Glycogen
What do Oligosaccharides contain?
Contain 3-10 sugar molecules
What do polysaccharides contain?
100s or 1000s of monosaccharide units , starch-digestible, fibre-indigestible
What is the linkage between cellulose ?
Glucose + glucose
-Beta 1-4 linkage
What does starch contain? what’s it made up of?
-Long chains of glucose units
1-Amylose
2-Amylopectin
3-Resistant starch- not digested
(found in grains, vegetables, legumes)
List the 3 forms of starch:
-Amylose
-Amylopectin
-Starch
Whats glycogen made up of?
Highly branched chains of glucose units
Body’s storage from carbohydrate
What type of linkage does Amylose have?
Alpha 1-4 linkages
-Straight chain
-25% of total plant starch
-Water soluble
What can the GI tract only absorb?
Monosaccharides - simplest form
What type of linkage does Amylopectin have ?
Alpha 1-4 linkages with alpha 1-6 linkage at branch points
-75% of total plant starch
(Not water soluble)
What’s glycogen composition?
“Animal Starch”
-Small amounts in the liver and muscle
-Highly branched
-Water soluble
What does Bruch border enzymes break down
Disaccharides
Indigestible Polysaccharides (structural CHO) (at least to monogastric) name them:
Cell wall carbohydrates… fibre
-Cellulose
-Hemicellulose
-Lignin
-Pectin’s
Non cell wall fibre
-Gums
-Cutin
What are oligosaccharides made up of?
Short chains (3-10)
What are non-starch polysaccharides made up of ?
Long chains
-Cellulose, hemicellulose, pectins, gums, mucilages
Other: Lignins, cutins, waxes
Where is complex carbohydrates or structural CHO found?
Found in fruits, veg, grains, legumes
What type of bond does the starch glucose molecules have ?
1:4 alpha bond
Where are the brush border enzymes found?
Anchor to the villi
What bonds does starch have between glucose molecules?
Alpha bonds between glucose molecules in starch that are easily broken by human digestive enzymes
What bonds does cellulose have between dietary fibres?
Beta bonds
What is important to know about alpha and beta bonds?
Human digestive enzymes easily can break down the alpha bonds in starch, but they cannot break the beta bonds in cellulose
Name some oligosaccharides and what are they metabolised by ?
-Dried beans, peas, lentils
metabolised by large intestinal bacteria (gaseous effects)
What does cellulose make walls of the cells?
Strong and rigid
How does an animal sweat?
Our sweat glands takes a sodium iodine and its put on the surface, osmosis occurs through the skin (water)
Whats hemicellulose mixed with in cell wall and what is the outer layer called?
-mixed with cellulose in cell walls
-outer bran layer
What does pectins form?
Gel forming; in fruit
What is gums and mucilage’s used for?
-Thick, gel- forming
-Used by food industry to thicken, stabilize
What does every cell have ?
sodium potassium pump- it removes sodium from the cell and brings salt in
sodium conc inside cell= low because the pump,
Sodium con fall down conc gradient, it brings glucose with it (SGLT1) Take glucose and sodium, take them through 1 permeable membrane to another , this is causing osmotic drain and it transfers with the glucose and sodium
what is the name of the indigestible substances that make up “woody parts” of veg; and fruit seeds
Lignin
What is cellulose major constituents of?
Paper, paperboard and card stock and textiles made from cotton, linen and other plant fibres
What type of carbs are on a food label?
-Starch “complex”
-Sugars “simple , fast acting”
-Fibre “mostly undigested”
What are foods made up of?
-proteins= repeating units of amino acids
-Fats= triglycerides
-Carbs= repeating units of glucose
Whats the definition for digestion?
Breaking down food into their simple molecules… the building blocks of the food.
Whats mechanical digestion -
chewing, chyme
whats chemial digestion
enzyme
What type of digestion happens in the mouth?
Carbs are broken down by salivary amylase and begins digestion of starch
Breaks down starch into maltose
No enzymes in ruminants
not all monogastric secrete saliva
What type of digestion happens in the small intestine?
– Pancreatic amylase completes starch
digestion
– Brush border enzymes digest disaccharides
Whats the end products of carbohydrate digestion?
– Glucose, fructose, galactose its absorbed into the bloodstream
Where is fibre digested?
digested in the small intestine its either fermented in LI or excreted in feces
What do 5-10% of polysaccharides break down into?
Dextrins
how much carbohydrate digestion happens in a monogastric stomach?
Very little, it mostly happens at the duodenum
What enzymes are used for carbohydrate digestion in the duodenum?
Pancreatic enzymes
Brush Border enzymes
What enzyme breaks down polysaccharides to disaccharides?
Amylase
What does the pancreatic amylase hydrolose and produce in the pancreas?
Hydrolyses CHO alpha 1-4 linkage
Produces- monosaccharides, disaccharides, polysaccharides.
Major importance in hydrolysing starch and glycogen to maltose
List brush border enzymes
Sucrose= glucose + fructose
Lactose= galactose + glucose
Maltose = glucose + fructose
What are the final digestion steps in the small intestine ?
Enzymes synthesised by cells lining the small intestine (brush border)
Disaccharides and broken down into monosaccharides by brush border enzymes
Whats is the exception for the Disaccharides to monosaccharide
Exception is B-1,4 bonds in structural CHO
Brush border enzymes what are they partially responsible for?
Unstirred water layer
-Temporal pattern of development and genetic component
what brush border enzyme do ruminants not have?
Sucrose
What is sucrose broken down into?
By Surcrose
to
Glucose + Fryctose
What is maltose broken down into?
by Maltase
to
Glucose + Glucose
What is Lactose broken down into?
by Lactase
to
glucose + galactose
What brush border enzyme does poultry not contain ?
lactase
List the 3 brush border enzymes
-Sucrose
-Lactose
-Maltose
What are disaccharides broken down into monosaccharides by?
Brush border enzymes
What is the final digestion mediated by enzymes synthesised by cells lining the small intestine called?
Brush border enzymes
What are brush border enzymes partially responsible for?
Unstirred water layer
What type of a linkage does maltase have?
alpha 1-6 glucose linkage
What make up sucrose?
glucose + fructose
What make up maltose?
glucose + glucose
What make up lactose?
glucose + galactose
What are the two processes that break down food?
mechanical breakdown
enzymatic breakdown
What does mechanical breakdown focus on doing?
chewing, smooth muscle contractions = increases the surface area
What does enzymatic breakdown focus on?
the breakdown of food into macromolecules for absorption
Name complex carbohydrates?
cellulose, glycogen, starch
whats the problem with cellulose complex carbohydrates?
not able to be digested i.e. roughage
Whats the story with glycogen and starch complex carbohydrates?
amylase breaks them down into disaccharides and brush border digestion occurs
What is maltase broken down into?
2 glucose
what is sucrase broken down into?
1 glucose, 1 fructose
what is lactase broken down into?
1 glucose , 1 galactose
In the mouth, dietary carbohydrates such as…. are broken down by…..
Starch, Glycogen, Sucrose, Lactose
Salivary amylase
When these dietary carbohydrates are broken down in the mouth by the …. what are they converted to…
Salivary amylase
Polysaccharides -sucrose, lactose, maltose
The … enter the stomach and nothing happens in the stomach. they enter the SI and … break them down into….
Polysaccharides such as - sucrose, lactose, maltose
Pancreatic amylase- sucrase, lactase, maltase
Monosaccharides
Absorption of the …. happen through the …. lining and the monosaccharides are…..
Monosaccharides
Small intestine lining
Transported into the blood stream.
Where is the primary site of absorption (carb absorption)
Jejunem
Whats the primary site of digestion (Carb Digestion)
Duodenum
What type of molecules are the only type that can be absorbed?
Monosaccharides
What molecule used facilitated diffusion?
Fructose
Name the two types of amylase?
-Salivary (where it starts)
-Pancreatic (where it ends)
What does amylase cleve?
alfa 1-4 glucose bond
What type of a bond does Maltase have?
alpha 1-6 glucose linkage
Name the sodium dependent glucose transporter?
SGLT1
What does SGLT1 transport?
2 Na+ molecules
1 glucose molecule
What type of concentrated gradient is a prerequisite?
Na+
What does the osmotic gradient pull and how many water/glucose molecules does it pull?
-Osmotic gradient pulls H2O
-260 molecules of water/glucose
Whats the regions of the small intestine?
-Duodenum
-Jejunum
-Ileum
Whats CHO malabsorption?
Simple CHO that should have been mostly digested and absorbed in the small intestine are not.
When CHO malabsorption happens whats the next step?
These simple CHO travel to the large intestine -Fermentation rates Structural CHO= Slow
Simple CHO= fast
Whats the cause of carbohydrate malabsorption syndrome?
– Enzyme deficiency, transporter deficiency, SI
diseases (Crohn’s, Celiac, pancreatic cancer)
How does carbohydrate malabsorption syndrome happen?
- 1) Osmotic effect in large intestine (LI)
- 2) Increases water in LI
- 3) Increases overall GIT peristalsis
- 4) Reduces nutrient retention time in
GIT….causes general malabsorption
Whats the colon typically the site of?
Water absorption
– Water content of feces is much less than it is in small
intestinal contents
What is the definition of lactose?
– Principal carbohydrate in milk and some dairy
products
* Fermented dairy products usually contain insignificant
amounts of lactose
– i.e. cheese, yogurts, etc.
What is lactose intolerance generally caused by?
- Genetic and Age dependent
Name the 2 variants of lactose sensitivity
Lactose Maldigestion
Lactose Intolerence
Whats the definition for Lactose Maldigestion
Incomplete digestion of
lactose, the natural sugar
in milk, due to low activity
of the lactase enzyme;
may be asymptomatic
Whats the definition for Lactose intolerance ?
Gastrointestinal
disturbances following
the consumption of an
amount of lactose
greater than the body’s
ability to digest and
absorb
Whats makes us produce gas and VFA’S in our large intestine?
Small intestinal derived undigested carbs such as fibre, lactose (in lactose intolerant people)
Microbial fermentation occurs and it produces Gas and VFA’s
what is also frowned upon and what causes it?
Diarrhea, its caused by an osmotic pull from the gas and VFA’S that where produced , the PH is lowered
What is some of the lactose in milk metabolised by ?
By microbes during the making of cheese and yogurts
What can be added to dairy products?
Supplemental B-galactosidase
what is Lactobacillus acidophilus?
its added to products to convert lactose to lactate “sweet acidophilus milk”
Name the different types of laxatives
- Hyperosmotic laxatives – MOA is at LI
- Stimulant laxatives – Irritate intestinal lining: increases peristalsis
- Saline laxatives – Prevents water absorption
- Bulk-forming laxatives – Increases intestinal extension
– Emollient laxatives – i.e. mineral oil
Name the different types of sweeteners (6 FDA Approved Compounds)
Saccharin
Aspartame – 4 kcal/g but miniscule amounts
Acesulfame-K
Sucralose
Neotame
Stevia
When was Saccharin discovered?
- Discovered in 1879
- 300-500 times sweeter than the sugar
sucrose - Undigested
Whats the story with Aspartamine
- 180 to 200 times sweeter than sucrose
- Upon digestion it breaks down into three
components (aspartic acid, phenylalanine
and methanol), which are then absorbed
into the blood and used in normal body
processes.
Advantages of the rumen?
1) Eat most abundant nutrient on planet
2) Microbes into each microbe is high quality. The amino acid of protein
Exam questions:
Why do lactose intolerant get diarrea?
