Bio - Unit 2

Only second part of the unit

4 biological molecules

1. Carbohydrates

2. Lipids

3. Nucleic Acids

4. Proteins

What is the monomer of carbohydrates?

Monosaccharides: glucose, fructose, galactose

What is the polymer of carbohydrates?

Polysaccharides

What is the monomer of proteins?

Amino Acids

What is the polymer of proteins?

Polypeptide/Proteins

What are the monomers of lipids?

Glycerol + Fatty Acids

What are the polymers of lipids?

Fats (Tryglicerides)

Phospholipids

Steroids

What is the monomer of nucleic acids?

Nucleotide
Made up of…

1) Phosphate

2) 5-carbon sugar

3) Nitrogenous base (only one that changes, can be C,G,A,T)

What are the polymers for nucleic acids?

DNA + RNA

DNA:

• Deoxyribose sugar

• A,T,C,G

• Double helix

RNA:

• Ribose sugar

• A,U,C,G

• Single stranded

Disaccharides

Two monosaccharides linked through dehydration synthesis

• Sucrose (table sugar)

• Lactose (in milk)

Skeletal Structural Formula

A representation of molecular structure in which covalent bonds are shown as lines (carbon and hydrogen may be left out.

What are the four polymers of carbs?

Energy storage:

Glycogen - animals (good inbetween meal storage)

Starch - plants (easy to digest)

Structural:

Cellulose - plants, strong cell walls (hard to digest)

Chitin - fungi (defsense/immune system)

What is the composition of Lipids?

C,H,O (very little oxygen)

What is the composition/ratio of carbs?

Carbon, Hydrogen, Oxygen

1:2:1

C₁H₂O₁

What is dehydration synthesis?

Formation of a new compound by removing water.

What is hydrolysis?

The chemical breakdown of a compound due to addition of water.

Fats (triglycerides)

Long, non-polar, hydrophobic chains of carbon and hydrogen

Composed of one glycerol molecule and three fatty acid chains

Functions:

• Long term energy storage

• Insulation

Saturated vs. unsaturated fats

Saturated fats

No double bonds

• animal fats

• solid at room temp

Unsaturated fats

At least one double bond C=C

• plant oils

• liquid at room temp (kinks/double bonds give more room to spread out)

Phospholipids

Glycerol molecule with two hydrophobic, fatty acid chains and a phospholipid head that is hydrophilic.

In water, the head will face the outside because it is polar, and the fatty acid chains will be on the inside

Functions:

• Insulation

• Cell Membranes

Steroids

• Cholesterol

• Progesterone

• Testosterone

Functions:

• Cell Membranes

• Signaling between cells

What are the functions of proteins?

Enzymes: speed up/catalyze chemical reactions

Collagen/Keratin: strengthens hair/nails (structural)

Transports hemoglobin (carries O₂)

Immunity/antibodies

Amino acids made up of Carboxyl, amino and R group (side chain)

Primary Structure of Protein

• Simplest level, polymer made up of chain of monomers

• Determined by sequence of amino acids

Secondary Structure of Protein

Made up of Alpha helices and Beta pleated sheets (more dimension)

Tertiary Structure of Protein

• Precise 3D shape of a fully folded protein

• Specific shape is fundamental to the protein’s function

• Different R-group leads to diversity in the 3D shape

Forces Contributing to Structural R-group Interactions (Proteins)

• Hydrophobic interactions

• Hydrogen bonds

• Ionic bonds

• Disulfide covalent bridges

Quaternary Structure of Protein

More than one peptide chain in final protein

Only occurs in some proteins

What is a peptide chain?

Sequence of amino acids beginning - end