Carbohydrates Flashcards
1
Q
What are Carbohydrates components of?
A
- Water and Carbon
2
Q
What molecules are carbohydrates made of?
A
- Hydrogen, Oxygen + Carbon
- Ratio 1:2:1 - CH20
3
Q
Read
A
CARBOHYDRATES ARE
- Main source of Energy for all living organisms –Glucose.
- Serve as structural components such as DNA – Ribose, Cell wall made up of cellulose.
- The simplest carbohydrates are sugar units also called saccharides.
4
Q
What are the 4 types of Carbohydrates?
A
- Monosaccharides (1 saccharide)
- Disaccharides (2 saccharide)
- Oligosaccharide (3 or more saccharides)
- Polysaccharide ( >10 saccharides)
5
Q
What are the simplest carbohydrates/ sugar units also called
A
- Saccharides also called sugar units.
6
Q
What are Monosaccharides?
give examples
A
- Simplest carbohydrates + can’t be hydrolysed to
smaller carbs. - End in -ose
- E.g. Glucose, Galactose, Fructose
7
Q
What is the functional group of a monosaccharide?
A
- Carbonyl Group
- Chemically organic functional group composed of a carbon atom double-bonded to an oxygen atom → [C=O]
8
Q
What are the 2 Carbonyl groups for a Monosaccharide?
A
- Aldehyde ( C=O bonded to at least one Hydrogen) always in C chain.
- Ketone ( C=O bonded to 2 Carbons) always w/in C chain.
9
Q
What do Aldehyde’s and Ketones turn to when they’re monosaccharides.
A
- Aldoses
- Ketoses
10
Q
Read
A
- Most common monosaccharide: 3-7 carbons (unbranched)
- No. of C atoms given by prefix: tri-, tetr-, pent-, hex-, hept-
- No. of carbons Generic Name: 3 Triose
4 Tetroses
5 Pentoses
6 Hexoses
7 Heptoses
11
Q
Read
A
- A 3C triose sugar with an aldehyde group = aldotriose sugar
- A 4C tetrose sugar with an aldehyde group = aldotetrose sugar
- A 5C pentose sugar with an aldehyde group = aldopentose sugar
- A 6C hexose sugar with an aldehyde group = aldohexose sugar
- A 7C heptose sugar with an aldehyde group = aldohepose sugar
- A 3C triose sugar with an ketone group = ketotriose sugar
- A 4C tetrose sugar with an ketone group = ketotetrose sugar
- A 5C pentose sugar with an ketone group = ketopentose sugar
- A 6C hexose sugar with an ketone group = ketohexase
- A 7C heptose sugar with an ketone group = ketoheptose sugar
12
Q
What are Chiral Centers?
see pics slide 11 +12 + 13 +14
A
- Chiral centers are tetrahedral atoms (usually C) that have 4 diff substituents.
- Molecules with “n” chiral centers have 2n stereoisomers.
- E.g. Glyceraldehyde: 1 chiral center
13
Q
What are Isomers?
A
- 2 compounds that have the same molecular formula, but have diff structural formulas.
14
Q
Read
A
- Ribose & Ribulose are isomers that differ by the location of the carbonyl group (C=O).
- In ribose the C=O belongs to an aldehyde
- In ribulose the C=O belongs to a ketone
- Ribose is classified as an aldose, Ribulose is a ketose
- Similarly Glucose & Fructose are isomers where glucose is an aldose & fructose is a ketose.
15
Q
What is the main source of energy for cells or humans?
A
- Glucose ( C6 H12 06)
16
Q
Read
A
- Look at slides 16 - 19
17
Q
How are monosaccharides attached to each other?
A
- By covalent bonds called Glycosidic bonds by a condensation rxn.
18
Q
Where are Glycosidic bonds formed?
A
- Between C 1 of a monosaccharide & a hydroxyl (OH) carried by a C atom in a diff monosaccharide molecule.
19
Q
Give an example of a Disaccharide?
A
- Maltose (2 glucose molecules covalently bind by a glycosidic bond.
- Lactose (Galactose + Glucose)
- Sucrose (Glucose + Fructose)
20
Q
Oligosaccharide example?
A
- Raffinose
- Stachyose
21
Q
What are Polysaccharides also called?
A
- Glycans
22
Q
Function of a Polysaccharide?
A
- Energy storage (glycogen in animal & starch in plant cells)
- Structural support (cellulose in plant cell wall)
23
Q
Examples of Polysaccharides?
A
- Glycogen
- Starch
- Cellulose
- Chitin
24
Q
Use of monosaccharides in animals?
A
- Glucose is carried by the blood to transport energy to cells throughout the body.
25
Use of monosaccharide in plants?
- Fructose
= sweet taste
= attracts animals
= disperse seeds
26
Use of disaccharide in animals?
- Glycogen = short-term energy store in liver & in muscles.
27
Use of disaccharide in plants?
- Sucrose – carried by Phloem to transport energy to cells
| through the plant.
28
Use of Polysaccharides in animals?
- Glycogen = short-term energy store in liver & in muscles
29
Use of Polysaccharides in plants?
- Cellulose = strong fibers, used to construct plant cell wall.
30
Read
1. Major source of energy which is available immediately as glucose.
2. When excess Carbohydrate is available it can be stored as glycogen in the liver & muscle cells of animals & starch in plants.
3. Forms Structural Tissue in - Plants - cellulose
- Animals – proteoglycans: teeth, cartilage
- Bacteria - cell wall
4. Found in the plasma membrane linked to lipids – glycolipids & play a role in structural integrity of the cell.
5. Found in the plasma membrane linked to proteins – glycoproteins & play a role in cell recognition.
6. Ribose sugar is important in the formation of DNA & RNA.
7. Proteins Sparing Action – when Carbohydrates are not sufficient in our body, proteins are broken down to fulfil the requirement of Carbohydrate.
8. Helps prevent Ketosis – in the absence of adequate Carbohydrate, large amounts of ketone bodies are produced in the blood. This increases the blood acidity. In severe cases this can lead to coma/death.
9. Provides Fibre – creates soft bulky stool that moves quickly through the large intestine.
