carbs pt 1,2,3,6 (basics,transported,fructose,RBC,NHANES)

carbohydrates are made up of

CHO

simple carbs include (2)

monosaccharides and disaccharides

sucrose is made up of

glucose and fructose **

lactose is made up of

glucose and galactose **

maltose is made up of

2 glucose molecules

complex carbs consist of (2)

oligosaccharides and polysaccharides

what are aldoses and ketoses

-aldoses have aldose

-ketoses have ketose group

what is chiral carbon

-assymetrical carbon

-when a carbon has 4 different atoms or groups covalently attached to it

-causes optical property **

what is stereoisomerism

the occurrence of a molecule in different espacial configuration

a straight chain monosaccharide is either _____ or ____

L or D

most hexoses are what configuration

D

what are enantiomers **

stereoisomers that are mirror images of each other but cannot be superimposed

what are diastereomers

2 or more chiral carbon atoms with the same four groups attached but not mirror images of each other

what is lactose intolerance, what is it caused by ***

cannot digest lactose due to lack of lactase enzyme

what are oligosaccharides

3-10 monosaccharide chain

what are polysaccharides

more than 10 monosaccharides linked together

what are the 3 functions of polysaccharides

storage, structure, and recognition

what are the 2 types of polysaccharides (based on units)

homopolysaccharide and heteropolysaccharide

what are homopolysaccharides

a polysaccharide that contains only ONE kinds of monosaccharide

what are heteropolysaccharides

a polysaccharide that contains several kinds of monosaccharide

starch and glycogen are ______ molecules

storage

chitin and cellulose are ________ molecules

structural

cell surface polysaccharides are __________ molecules

cell recognition

starch is made up of

amylose and amylopectin

starch breaks down to _________ when digested **

glucose

where is glycogen found in the body

liver and skeletal muscle

what are the 4 functions of carbs

• Carbohydrates Supply Energy

• Fuel for the Central Nervous System (CNS) and Red Blood Cells

• Carbohydrates Provide Fuel for the Muscular System

• Carbohydrates spare protein and prevent ketosis

NOW ONTO DIGESTION/ABSORPTION/TRANSPORT/DIFFUSION

what digestion of carbs occurs in mouth

salivary amylase breaks down starch into oligosaccharides and maltose by cleaving 1—>4 bond

what carb digestion occurs in stomach

none because amylase is inactivated by acid

what kind of digestion of carbs occurs in the small intestines

pancreatic amylase breaks down starch into oligosaccharides and maltose by cleaving 1—>4 bond

where does digestion occur in the small intestines (through what structure)

microvilli

how are carbs absorbed (what form)

as monosaccharides

(all sugars at this point are hydrolyzed into monosaccharides to be absorbed by enterocytes)

FRUCTOSE ABSORPTION TOPIC

how is fructose taken into the enterocyte (what transporter)

GLUT 5

TRANSPORT

What are the 2 main types of sugar transporters

SGLTs and GLUTs

SGLTs are what type of transport

active (rely on the movement of Na+ for energy)

what type of transport are GLUTs

facilitated transport

what transporter allows fructose to leave enterocyte and enter blood

GLUT 2

GLUT TRANSPORTERS TOPIC

GLUT isoforms are what kind of proteins

integral proteins

GLUT 1 is used for what?? (what cells and locations)

Main is blood brain barrier AND red blood cells

red blood cells and ATP (pathway to make energy) ***

-do not have mitochondria so not use TCA cycle

-make ATP through anaerobic respiration (glycolysis)

GLUT 2 transporters are found in what cells (4)

pancreas, liver, small intestines, and kidney

GLUT 2 transport what sugars

glucose and fructose

GLUT 2 works how?

GLUT 2 is always placed to allow glucose to enter the bloodstream. GLUT2 only comes to the surface of the cell to allow intake of glucose into cell when glucose is available (low affinity), so during carb rich meal. Then when insulin is released GLUT2 removes itself from the surface once again. Glut 2 however is used to move glucose from cells to blood constantly

GLUT 2 is involved in release of what hormone from beta cells

INSULIN

• When glucose enters the pancreatic cell through GLUT2 transporter is causes triggers that depolarize the cell which causes insulin to be released

GLUT 3 is expressed where (1)

neurons

GLUT 4 is found where in the body **

MUSCLE and adipose tissue

GLUT 4 is dependent on what hormone **

INSULIN

When insulin is not present, GLUT 4 is stored where

in GSVs (GLUT 4 storage vesicles)

how does GLUT 4 move to the surface of cell to allow glucose into muscle and adipose tissue

When there is insulin, the GSVs are stimulated and transported by elements of the cytoskeleton. They dock with the plasma membrane for fusion and their lipid bilayers fuse. Glut 4 becomes part of the cell membrane and is available for transporting glucose into the cell.

• When there is no insulin, GLUT4 stays in the GSVs and its presence in the cell membrane is reduced.

GLUT 5 is used for transport of what sugar ***

FRUCTOSE

Fructose is not found where and why (hint: systemic) ***

not in systemic circulation because it is efficiently removed and metabolized by the liver

GLYCEMIC RESPONSE TOPIC

what 2 hormones are involved in blood glucose concentration**

insulin and glucagon

what pathway is involved in blood glucose concentration

glycogenesis

define glycemic index

increase in blood glucose during 2-hour period after consuming a contain amount of CHO compared with equal CHO from reference food

cons of Glycemic Index

-depends on prep, ripeness of the CHO source

-affected if CHO eaten with other things

-tells us nothing about nutritional value

-doesnt reflect amount we would actually eat of the food

define glycemic load

considers the quantity and quality of CHO in a food

-GI x grams of CHO in typical food portion

PERSPECTIVE (WHAT DO AMERICANS EAT) TOPIC

what do we use to assess the health and nutritional status of adults and children in the US?

NHANES!!!

What has NHANES discovered/found for us (like what has its findings been used for) (4)

• Determine the prevalence of major diseases and risk factors for diseases.

• Assess nutritional status and its association with health promotion and disease prevention.

• Basis for national standards for such measurements as height, weight, and blood pressure.

• Used in epidemiological studies and health sciences research