Unit 3: Carbohydrates (Part 1) Flashcards
Carbohydrates are primary source of _______ for brain, erythrocytes, and retinal cells in humans
energy
T/F: Nervous tissue can concentrate/ store carbohydrates
FALSE
T/F: Glucose can cross the BBB
TRUE
T/F: RBC can produce glucose
FALSE
What is the role of glucose to RBC?
Maintains a healthy RBC and free from oxidative stress
Carbohydrates is the major food source and energy supply for the body and stored primarily as ________ in the ________ and _____________
Glycogen; Liver; Muscles
Carbohydrates is involved in two disease states:
Hyperglycemia and Hypoglycemia
Carbohydrates is important for the diagnosis of?
Diabetes mellitus
Carbohydrates are substances containing these 3 elements:
Carbon, Hydrogen, Oxygen
There is 1 _________ per carbon
Water
All carbohydrates contain these two functional groups:
Carbonyl (C=O) and Hydroxyl (OH)
Carbohydrates are hydrates of ____________ because they contain _________
Carbon; Water
Carbohydrates can be classified based on these 4 structural properties:
- Size or number of the base carbon chain
- Location of the CO functional group
- Number of sugar units
- Stereochemistry of the compound
Based on size or number of base carbon chains, carbohydrates can be classified as:
- Trioses (3C)
- Tetroses (4C)
- Pentoses (5C)
- Hexoses (6C)
Examples of Pentose:
Ribose, Deoxyribose
Examples of Hexose:
Glucose, Fructose, Galactose
Smallest carbohydrate, a three-carbon compound
Glyceraldehyde
Based on the location of CO functional group, carbohydrates can be classified as:
- Aldose
- Ketose
In aldoses, the carbonyl group can be found at the:
Terminal
Functional group of aldose
Aldehyde group
In ketoses, the carbonyl group can be found at the:
Middle
Functional group of ketose
Ketone group
Two carbohydrate models
- Fischer projection
- Haworth projection
In Fischer projection, the aldehyde or ketone group can be found at:
the top
In Fischer projection, carbons are numbered starting at the:
Aldehyde or ketone head (at the top)
In Haworth projection, the compounds are represented in:
Cyclic form
Haworth projection is formed when the functional group reacts with ________ group on the same sugar to form a _______
Alcohol; Ring
Based on number of sugar units, carbohydrates can be classified as:
- Monosaccharides
- Disaccharides
- Oligosaccharides
- Polysaccharides
This is the simplest sugar, based on the number of units
Monosaccharides
T/F: Monosaccharides can be hydrolyzed
FALSE
Examples of monosaccharides
- Triose
- Tetrose
- Pentose
- Hexose (Glucose, Fructose, Galactose)
____________ are two monosaccharide units linked by ______________
Disaccharides: Glycosidic bonds
When two monosaccharides are joined together, water is ______________
released
If we want to split disaccharides, _________ is done
Hydrolysis
Water is _________ if disaccharides are split
consumed
Maltose is composed of these two monosaccharides
2 D-glucose units
Lactose is composed of these two monosaccharides
1 unit of glucose + 1 unit of galactose
Sucrose is composed of these two monosaccharides
1 unit of glucose + 1 unit of fructose
Sucrose is also known as:
Common table sugar
Lactose can be found in:
Milk
Oligosaccharides have ________ sugar units
3-10 sugar units
T/F: Oligosaccharides have few sugar units, composed of more than 10 sugar units.
FALSE, while it is true that it is composed of few sugar units. It is only composed of 3-10 sugar units.
Polysaccharides have ______ sugar units
More than 10 sugar units
Examples of Polysaccharides:
Glycogen and Starch
T/F: Central carbons of a carbohydrate are asymmetric
TRUE
This allows for spatial arrangement in the molecules
Chirality
This is the spatial arrangement in the molecules
Stereoisomers (Enantiomers)
Enantiomers are identified by:
Hydroxyl group
Enantiomers cannot be overlapped or ______________
Non-superimposable
Most sugars in humans are in which enantiomeric form?
D-form
Stereoisomers have the same:
Order and types of bonds
Stereoisomers have different:
Spatial arrangement and properties
If the OH group is found on the right of Fischer projection, it is a:
D-isomer
If the OH group is found on the left of Fischer projection, it is a:
L-isomer
Most ingested carbohydrates:
Polymers: Starch and Glycogen
Digestion starts here
Mouth
This enzyme is essential for digestion, and is produced by the salivary gland:
Salivary amylase
Starch is broken down into these two units with the help of amylase:
Disaccharide and Dextrin