Module 7 and 8 Flashcards
(24 cards)
What are carbs-?
Hydrated carbon- such as starch, cellulose, glycogen, lactose
Bulk of dry matter in feeds
What is the primary monosaccharide?
Glucose- an energy substrate and CNS requirement- blood levels too low is diabetes- fermented to VFA in ruminants-
What’s an aldose?
Monosaccharide that is an aldehyde - triose?
What is a ketose?
A ketose is a monosaccharide containing one ketone group per molecule
What are the functional groups that can occur on a carb such as glucose and fructose-?
Carbs can contain hydroxyl (alcohol) groups, ethers, aldehydes and/or ketones
Alkanes too-??
Based on the # of carbon atoms in a single carb molecule, how would the carb be defined?
Three carbon monosaccharides are called trioses, four carbon are called tetroses, five carbon are called pentoses, six carbon are hexoses, and so on.
When glucose structure changes from the open chain form to the more common cyclic structure, how dies this change how you would draw its structure?
The glucose now is more of a cynic structure- this is caused by the alpha and beta
when the hydroxyl group on carbon 5 (C5) bonds to the aldehyde carbon 1 (C1)
What is the anomeric carbon-?
The cyclic form of glucose is a six-membered ring, with an intramolecular hemiacetal formed by attack of the hydroxl on the fifth carbon on the aldehyde carbon (C1) - carbon 1
What happens when an alcohol adds to an aldehyde?
Hemiacetal formed
What happens when an alcohol adds to a ketone
Hemiketal formed
When starch is bonded to another to form polysaccharides, what is the specific bonding structure called for a linear chain?
Polysaccharide made up of glucose
**The glucose molecules are bonded together as α-(1→4) glycosidic bonds
When cellulose is bonded to another to form polysaccharides, what is the specific bonding structure called for a linear chain?
Polysaccharide made up of glucose
**The glucose molecules are bonded together as β-(1→4) glycosidic bonds
Cellulose structure contains many hydrogen bonds as well, which gives it such a rigid structure
If the polysaccharide is amylopectin [starch with a lot of branch points], or glycogen what is the other bonding that occurs in it that results in branching-?
Resembles amylopectin with the α(1→4) and α(1→6) branches, but there is more branching in glycogen (2.5 times more)
What are the polysaccharides that occur in
Forages?
Grains?
Animal tissue?
Forages- cellulose
Grains- starch
Animal tissues- glycogen
Milk- lactose
When glucose is metabolized by rumenal bacteria, what is the term that describes this process because it involves microbial metabolism?
Fermentation and the VFA when glucose is metabolized by rumen bacteria
What are the byproducts formed that the animal makes use of when glucose is metabolized by rumen microbes?
VFA- the glucose in the rumen will be fermented- when microbes are done with it then it is now the byproducts
How will the animal derive its glucose if it’s a ruminant?
Glycolysis
The animal can form glucose in the liver that it sends through Heptic Portal Vein
What is propionate?
VFA -is glucogenic in ruminants
Propionate is converted to glucose by the liver – the “glucogenic VFA”
What happens to the excess VFA that the animal absorbs?
It goes for fat production
If the animal is a non-ruminant how is the glucose digested and absorbed?
In the small intestine
Amylase – digests the α(1→4) bonds
•Debranching enzyme – digests the α(1→6) bonds of branched glucose polymers
•Free glucose (and galactose) enters the intestinal cell (enterocyte) by “active transport”
•Sodium-glucose co-transporter
•ATP required to “pump” the sodium out
What are the enzymes that are needed by the animal or the microbes if a ruminant for digestion of starches, cellulose, or the branch points of the more complex polysaccharides?
Starches- amalase
Cellulose- cellulase
Branch points- deb ranching enzyme-!
What are VFAs?
carbohydrates --microbial fermentation--> VFA short=chain fatty acids produced by microbes (rumen, cecum, colon) 3 types: -acetic acid (2c) -propionic acid (3c) -butyric acid (4c) absorbed passively provide 70-80% ruminant's energy needs
How does the animal respond to digesting carbs and absorbing glucose so that after the glucose is in the animal’s system it can be taken up by the cells of the various tissues and organs?
Through Glucose Transport Protein 4- Glut 4
GLUT4 is the insulin-regulated glucose transporter
If the ruminant animal abruptly consumes a high-starch feed after having been consuming high-forage feeds for a long time, what can happen in the rumen that will ultimately affect the animals blood and its health-?
They can get acidosis- lactic acid buildup for decline in pH in the rumen-?
Perhaps. Perhaps not :P
Either way they’re fucked up with acidosis.
