BioChemistry

Chapter 2.3

Organic Compounds

• Compounds made by cells and containing carbon

• A carbon atom has 4 electrons in its outside shell– Does it make covalent or ionic bonds?

• covalent

Macromolecules

• Large molecules• Examples: Proteins,

Carbohydrates, Lipids, Nucleic Acids

How do you make a macromolecule?

• Need small building blocks– These are called Monomers

• Link monomers together you get – Polymers

• Greek – Poly (many)– Meros (parts)

How do you make a macromolecule?

• You must link the monomers• You must remove a hydrogen ion & a hydroxide ion• These will form water• The process is called –

– condensation

Condensation

Can you break the Macromolecules apart?

• Yes• Just add water• Hydrolysis

– Hydro = water– Lyse = break

Lipids

Fats• Mostly carbon

and hydrogen• They store

energy• Monomers –

– Glycerol– Fatty acids

• Triglyceride (fat in the blood)

Saturated Fats

• Saturated fats have the maximum number of hydrogen

• Are solid at room temperature

• Most animal fat

Read those labels!!!

•Diets rich in saturated fats may contribute to cardiovascular disease

•Called atherosclerosis

Lipid deposits called plaques build up in blood vessels

Unsaturated Fats

• Contain double bonds

• Liquid at room temperature

• Most vegetable fats

So what is hydrogenated vegetable oil?

• Take unsaturated fats• Pump them full of

hydrogen atoms• Presto! –

hydrogenated vegetable oil – UNHEALTHY!

Other forms of lipids

• Phospholipids– Major component of

cell membranes– Contain phosphorus &

fatty acids

• Waxes– Fatty acids and alcohol– Natural coating for

fruits– lipstick

• Steroids– Lipids bent to form

rings– Found in animal cell

membranes– Starting material to

make male and female sex hormones

Proteins -

Essential to theStructure

&Function of Life

Proteins

• From the Greek word “proteios”– First place

• Most diverse in structure & function

• Monomers– Amino acids

• Consisting of an amino group and a carboxyl group covalently bonded together

How do proteins form?• Monomers are linked

by condensation – The OH from the

carboxyl group binds with the H from the amino group

– The amino acid is held together by a peptide bond

• 2 amino acids = dipeptide bond

• 3 or more amino acids = polypeptide bond

7 Major Classes of Protein

1) Structural – includes spider silk, human hair, & fibers that make up tendons & ligament

2) Contractile – provide muscular movement

3) Storage – ovalbumin (egg white)

4) Defensive – antibodies

7 Major Classes of Protein cont…

5) Transport- hemoglobin (iron containing protein in blood)

6) Signal – hormones coordinating body activity

7) Enzymes – serves as a chemical catalyst (changes the rate of a chemical reaction without being changed)

Carbohydrates

• Composed of carbon, hydrogen, & oxygen

• Ratio of 1:2:1• Monomer

– Simple sugar – monosaccharides

Carbohydrates cont.

• Disaccharides – double sugars– Example - sucrose

Carbohydrates cont.

• Polysaccharides – many sugars– Examples – starch, cellulose, chitin