Chapter 3: Organic Molecules

organic molecules

molecules that contain carbon and hydrogen

Why does carbon bond with four other elements?

It is to gain four more electrons since Carbon only has four electrons in its outer shell. Carbon normally shares electrons with Carbon, Hydrogen, Oxygen and Nitrogen.

Hydrocarbons

Chains composed of carbon and hydrogen

Functional Groups (R-groups)

molecules that are attached to hydrocarbons that gives them their properties.

Monomer

small chemical unit that makes up a polymer

Polymer

A long molecule consisting of many similar or identical monomers linked together.

Dehydration Synthesis

WATER is REMOVED from the chemical reaction, which then allows monomers to bond

Hydrolysis

WATER is ADDED to break bonds.

Polymers => Monomers

Carbohydrates

energy source and also used for organism's structure.

monosaccharides

single molecule (simple sugar)

ex. glucose

Disaccharides

two monosaccharides bonded together

ex. Maltose (glucose + glucose)

Polysaccharides

large molecules formed by multiple monosaccharides. Energy storage molecules

Starch = glucose storage for plants

Glycogen = glucose storage for animals

Structural: cellulose for plant walls and chitin for lobsters

Lipids

long chains of carbon and hydrogen

used for: cell membrane, waterproof skin, hair, feathers. Also used for long-term energy storage

ex: steroids, fats, phospholipids

Saturated Fats

SOLID at room temperature. It does not have double bonds.

ex: Butter

Unsaturated Fats

LIQUID at room temperature. Has double bonds.

ex: oil

Triglycerides

composed of 1 glycerol and 3 fatty acids.

storage for extra calories

Phospholipids

a lipid consisting of a glycerol bound to two fatty acids and a phosphate group.

Present in the cell membrane: Polar head and non-polar tail

Steroids

lipids with four fused ring carbon skeletons

Cholesterol

Steroid common in cell membranes, also in many hormones.

Proteins

Consists of one or more polypeptide (chain of amino acids)

Used in cell defense, storage, communication movement, and structural support.

Amino acids

organic molecules with carboxyl and amino groups

r group determines its properties

It is a monomer

Polypeptides

long chains of amino acids

it is a polymer

Four levels of protein structure

primary, secondary, tertiary, quaternary

primary structure

sequence of amino acids

secondary structure

Either an alpha helix (coils) or beta pleated sheet (folds) in polypeptide chain. (via H-bonds)

tertiary structure

interactions of the R groups of the amino acids making up the chain.

quaternary structure

Results from two or more polypeptide subunits.

nucleic acids

Polymers of nucleotide monomers.

DNA and RNA

composed of phosphate, 5-carbon sugar, and nitrogen base

DNA

Deoxyribonucleic Acids

Sugar: Deoxyribose

Double Helix

stores genetic information

(Bases: Guanine, Adenine, Thymine and Cytosine)

RNA

ribonucleic acid

Sugar: Ribose

Single-stranded

helps to make protein

(Bases: Guanine, Adenine, Uracil and Cytosine)

Central Dogma

DNA gets Transcribed (Transcription) to RNA. Then, RNA gets Translated (Translation) to Protein