Biology SL Unit 1 - Organic Molecules

Chemical formula for glucose

C₆H₁₂O₆

Alpha glucose’s OH is facing ___, beta glucose OH is facing ___

down, up

Glycosidic bond

Covalent bond between two glucose molecules

Starch is made up of ___

alpha glucose molecules

Starch’s function is:

energy storage in plants

Describe Amylose:

linear, 1-4 glycosidic bond, coiled structure.

Describe Amylopectin:

branched, both 1-4 and 1-6 glycosidic bonds, 3D branched structure (efficient storage of glucose)

Glycogen is made up of:

alpha glucose molecules

Name the three polysaccharides of glucose (carbs)

1. Starch

2. Glycogen

3. Cellulose

Describe Glycogen:

branched, both 1-4 and 1-6 glycosidic bonds, more branches than amylopectin

Glycogen’s function is:

Efficient storage of glucose in animals

Cellulose is made of:

beta glucose molecules

Describe Cellulose:

linear, 1-4 glycosidic bonds, repeating flat sheets held by hydrogen bonds. H-bonds between layers create tensile strength and stability. Straight linkage of b-glucose creates strong and rigid structure.

Cellulose’s function is:

in plant cell wall: maintain shape and integrity, withstand osmosis, protection.

Glycoproteins are:

proteins that have 1 or more carbs attached to it

Function of glycoproteins:

1. Cell-cell recognition: acts as markers on a surface of cells for identification

2. Receptors: receive signals from other cells

3. Ligands: binds to specific receptors to initiate things

4. Structural support: contribute to structural integrity

Properties of lipids:

1. hydrophobic

2. long term storage (higher atp yield)

Lipid’s functions:

SHIPS: Storage, hormonal, insulation, protection, structural

Triglycerides are made of:

1 glycerol + 3 fatty acids

The covalent bond between fatty acids and glycerol is:

Ester bond

Phospholipids are made up of:

1 glycerol modified with phosphate + 2 fatty acids

Phospholipid

Triglycerides

Hydrocarbon chains are:

Backbone of fatty acids, long linear chains of hydrogen & carbon

Describe Saturated fatty acids:

linear and no double bonds, tightly packed, solid

saturated fatty acid

Describe Unsaturated fatty acids:

bent structure, 1 or more double bond, hard to pack, liquid

unsaturated fatty acid

The more double bonds in fatty acids =

the weaker the fatty acid

Unsaturated fatty acid’s melting point is __ than saturated

lower

Describe cis unsaturated fatty acids:

bent, natural, loosely packed

cis unsaturated fatty acid

trans unsaturated fatty acid

Describe trans unsaturated fatty acids:

straight, man-made, rigid

Cis fats have H-atoms on ___ side, trans have on ___ side

same, different

phospholipid bilayer

Describe the phospholipid bilayer:

hydrophilic phosphate head, hydrophobic fatty acid tail, amphipathic but overall hydrophobic

amino acid

Label the different groups

Amino, side chain/R group, carboxyl

Peptide bond:

covalent bond between carboxyl + amino group

Draw the formation of peptide bond

Draw the formation of ester bond

What causes denaturation

1. temperature (breaks H-bonds)

2. pH (affects solubility and charge)

nucleotide

polymerization is

(condensation) forming nucleic acids from nucleotides

Purines are:

1 ringed base (Adenine and Guanine)

Pyrimidines are

2 ringed bases (cytosol & thymine & uracil)

Bond between nucleotides are:

phosphodiester bonds

G - C bonds have __ H-bonds, while A - T/U bonds have __ H-bonds

3, 2

Describe DNA

deoxyribose sugar, stable long term storage of information, no oxygen, double stranded, contains thymine

Describe RNA

ribose sugar, copy of DNA, short term information storage, contains uracil, single stranded, OH group

ribose sugar

deoxyribose sugar

Define nucleosome

DNA wrapped around protein (histones)

Enzyme-substrate specificity models

lock and key (specific enzyme for specific chemical reaction)

induced fit model (enzyme active site changes to fit substrate)

What happens to an enzyme when substrate concentration is too high?

becomes saturated