Biochemistry!

Subtopics are highlighted, terms are bolded, and definitions are underlined :)

Organic Molecules:

What are organic molecules?

Organic molecules contain carbon, and hydrogen bonds. 

Carbon is the chemical backbone of the macromolecules found in your body.

Inorganic molecules don't contain carbon or hydrogen bonds.

The Major Biological Elements...

C - carbon

H - hydrogen

O - oxygen

N - nitrogen

P - phosphorus

S - sulfur

There are four major categories of organic molecules found in living things.

Carbohydrates, lipids, nucleic acids, and proteins.

These are referred to as macromolecules because of their size.

Macromolecules - large molecules formed by the joining of small molecules

Monomer - a small molecular unit that is the building block of a larger molecule

Polymer - a long chain of small molecular units connected together

How do you make or break down a polymer?

Dehydration synthesis is the process used to build polymers.

Hydrolysis is the process used to break down a polymer.

Carbohydrates:

What are carbohydrates?

Carbohydrates are organic compounds made up of sugar. 

C:H:O ratio = 1:2:1

What are the functions of carbohydrates?

Energy - all living organisms use carbohydrates as their main source of energy

Structural Support - plants, and animals with exoskeletons also use carbohydrates for structural purposes

Monosaccharides - simple sugars containing just one sugar unit, ex. glucose, fructose, and galactose

Monosaccharides are the main supply of energy for cellular work. The monosaccharides that aren't immediately by cells are usually incorporated into larger carbs or they are used to make fat molecules.

Disaccharides - consists of two sugar molecules connected together

In order to be used as energy, disaccharides must be broken down by hydrolysis into two monosaccharides. 

Polysaccharides - long polymer chains made up of simple sugar monomers

There are four types of polysaccharides...

Starch - sugar storage molecules for plants

Glycogen - sugar storage molecules for animals, found in the muscles and liver

Cellulose - a structural building material for plant cell walls

Chitin - a structural building material for animal exoskeletons

Lipids:

What is a lipid?

Lipids are hydrophobic compounds, that don't dissolve in water, ex. fats, oils, steroids, waxes.

What are the functions of lipids?

Lipids are long-term energy storage and are the structural components of the cell membrane. Some act as hormones, which are chemical signals that trigger a response at the target cells. Lipids also help insulate the body.

Fat - consists of one glycerol, and three fatty acid tails

They are also called triglycerides. Fat is hydrophobic and used for long-term energy storage.

There are three different types of fat...

Saturated Fat - a fat in which all three fatty acid chains contain the max number of hydrogen atoms, ex. butter

Unsaturated Fat - contains less than the max number of hydrogen atoms in one or more of its fatty acid chains, ex. corn oil, vegetable oil

Trans Fat - an unsaturated fatty acid which has the hydrogen atoms of the carbon double bonds on opposite sides of the double bond

Trans fat is formed during a process called partial hydrogenation and is considered to be the worse type of fat. It raises your bad cholesterol and lowers your good cholesterol.

Phospholipids - has a hydrophilic head group (made of phosphate and glycerol) and two hydrophobic tails (made of fatty acids)

What are the functions of phospholipids?

Phospholipids are the major component of cell membranes. They define the cell border.

Steroids - a category of lipid molecules in which the carbon skeleton forms four fused rings, hydrophobic

Cholesterol - an essential molecule found in the membranes that surround the cells, a precursor to bile, vitamin D, and steroid hormones

LDL - transport cholesterol from the liver to tissues that incorporate it into cell membranes

HDL - carries old cholesterol that has been discarded by cells back to the liver for recycling or excretion

Nucleic Acids:

What are the functions of nucleic acids?

Nucleic acids store and transmit genetic information, includes genes which are instructions for building proteins.

Two types of nucleic acids are DNA and RNA.

Proteins:

What are proteins?

Proteins are functional polymers composed of amino acids.

 What are the functions of proteins?

Enzymatic Proteins - speed up chemical reactions

Transport Proteins - transport substances in and out of the cell

Structural Proteins - keratin and collagen

Hormonal Proteins - coordinate cell activities

Receptor Proteins - receive messages from other cells

Motor and Contractile Proteins - movement

Energy - only if necessary

Chemical Reactions and Enzymes:

Metabolism - the combination of chemical reactions through which an organism builds up or breaks down molecules

The two types are anabolism and catabolism.

Anabolism - builds up molecules, ex. dehydration synthesis

Catabolism - breaks down molecules, ex. hydrolysis

What are chemical reactions?

Chemical reactions breaking of old and formation of new chemical bonds that result in new substances.

Activation Energy - start-up energy for a reaction to occur and allows the reaction to occur faster than if enzymes weren't present

What are enzymes?

Enzymes increase the rate of reaction and speed up both anabolic and catabolic chemical reactions. They are specific, meaning their shape determines their function. They catalyze only one type of reaction and can be reused. Enzymes usually are made of proteins and end with the suffix -ase.

Substrate - the specific reactant acted upon by an enzyme

Active Site - the substrate fits into a particular site, where the reaction takes place

pH - describes how acidic or basic a solution is

The range goes from 0, most acidic to 14, most basic. The pH of 7 is neutral, neither acidic or basic.

Enzyme Inhibitor - a molecule that binds to an enzyme and reduces its activity level, ex. cyanide binds to the iron atom of the enzyme cytochrome