Carbohydrates Flashcards
What is a MONOMER?
Smaller molecules that make macromolecules
What is a DIMER?
Macromolecule of CHEMICALLY BONDED monomers
What is a POLYMER?
Many macromolecules
Four function of carbohydrates?
Energy production and storage (starch, glycogen and glucose)
Recognition and signalling: at cell membrane, attached to proteins and phospholipids creating glycoproteins and glycolipids, which play a role in cell to cell communication.
Building blocks of DNA / RNA with back bone of 5-carbon pentose sugar and a phosphate.
Structure (cellulose with long chains forms tough protective walls for plant cells
Three forms of carbohydrates?
- Monosacchardies (monomers)
- Disaccharides (dimers)
- Polysaccarides (polymers)
What are carbohydrates made of?
Carbon, Hydrogen and Oxygen
What are simple and complex carbohydrages?
SIMPLE: mono and disaccharides.
COMPLEX: Polysaccharides
Name three monosachharides.
How many carbons do they have, and what groups are they bound to?
3-9 carbon sugars bound to hydroxl (-OH) groups.
- Glucose
- Galactose
- Fructose.
Name three disaccharides?
- Sucrose
- Lactose
- Maltose
What is cellular respiration?
A metabolic process within the cell where biochemical energy is harvested from organic substances (usually glucose) and stores as ATP for energy requiring cellular activities.
Name four polysaccharides?
- Starch
- Fibre
- Glycogen
- Cellulose
What’s an isomer?
Give monosaccharide example
Same chemical formula but different arrangement.
alpha and beta glucose are examples, difference is only placement of -OH (down for alpha and up for beta). Fructose is also an isomer of glucose, but is 5-sided and very different structure. All are C6H1206.
Different function of alpha and beta glucose?
Alpha glucose is used to produce ATP during cellular respiration. Beta glucose used to sythesise cellulose (polysaccharide). Both are 6-carbon sugars (hexose).
What’s a disaccharide? How are they formed?
Two monosaccharides that have bonded together with a glycosidic bond in a condensation reaction.
Three examples of disaccharides?
Sucrose (glucose + fructose)
Lactose (glucose + galactose)
Maltose (glucose + glucose)
What is a condensation reaction?
Chemical process of two molecules making a larger more complex bio molecule involving the loss of a water molecule. The basis of synthesis of all complex macromolecules: glycogen, starch, cellulose.
Explain maltose as condensation reaction?
Maltose is formed by condensation of two glucose molecules. Both have spare -OH nearby; H20 is released, and -O- is formed. Can be created frequently to make a polysaccharide. As it’s the 1-carbon and 4-carbon, can be called a-1-4-glycosidic link.
What is a hydrolysis reaction?
Breaking bond with addition of H20 molecule.
How is the disaccharide maltose broken down?
Hydrolysis reaction.
Matlase (found in phospholibid bilayer of the epithelial cells lining villi of small intestines) adds -OH and -H on either side of the glycosidic bond, replacing the H20 and creating the two monosaccharides of glucose.
Chemical formula of condensation and hydrolysis of Maltose?
C6H12O6 + C6H12O6 –> C12H22O11 + H20
C12H22O11 –H2O–> C6H12O6 + C6H12O6
Name three polysaccharides and discuss their solubility.
- Starch
- Glycogen
- Cellulose
Insoluble in water; good forms of storage as they don’t influence the osmotic balance of cells.
How is starch used by the body?
Complex storage compound stored in roots of plants.
Amylase produced by salivary glands in mouth hydrolysis reaction to create Maltose.
Second hydrolysis reaction using maltase in small intestines to form glucose.
Glucose then transported through epithelial cells lining the villi via facilitated diffusion and active transport, absorbed into the blood stream (with O2) and transported to respiring cells.
Moderately branched.
Insoluble in water thus doesn’t effect osmotic balance of cells.
How is glycogen used by the body?
Made from pure glucose, stores as energy reserve in muscles and liver cells. Formed by successive condensation reactions.
Highly branched.
Insoluble in water thus doesn’t effect osmotic balance. of cells.
Four biological functions of carbohydrates
ENERGY PRODUCTION AND STORGE:
Polysaccharides glycogen and starch.
(main carbohydrate: glucose).
RECOGNITION/SIGNALLING: At cell membrane carbohydrates attached to :
- proteins forming GLYCOPROTEINS
- phospholipids called GLYCOLIPIDS
play a role in cell to cell communication.
BUILDING BLOCKS FOR DNA/RNA: Backbone of these nucleic acids are made of pentose 5-carbon sugar (dioxyribose and ribose) and a phosphate group.
STRUCTURE: Cellulose is made of long strands, which helps form the tough protective layer around plant cells.
