U 1: Biochemistry

Characteristics of Life

• Highly Organized

• Composed of Cells

• Reproduce

• Based on genetic code like DNA and RNA

• Growth and development

• Obtain and use energy

• Respond to stimuli

• Maintain Homeostasis

• Have a limited lifespan

Chemistry Review

Define element: a substance that cannot be broken down into any other substance

What is an atom? the basic unit of a chemical element

Most common elements found in living organisms: CHONPS

Carbon Hydrogen Oxygen

Nitrogen

Phosphorus

Sulfur

What are the 3 types of bonds that form between atoms?

Covalent:

• Atoms share valence electrons. There can be more than one covalent bond per molecule (single bond, double bond, triple bond) VERY STRONG BOND, but not as strong as ionic.

Ionic:

• One atom “accepts” or “donates” one or more valence electrons to another atom. Ion–charged particle STRONGEST BOND

Hydrogen:

• interaction involving a hydrogen atom located between a pair of other atoms having a high affinity for electrons

Characteristics of water definitions:

Cohesion:

• Water bonding to water

Adhesion:

• Water bonding to something else

Universal solvent:

• Water’s polarity allows it to be attracted to other polar or ionic compounds. Since water is small and polar, it easily surrounds other molecules and the attraction between the water and the charged atoms in the compound will split the compound apart (dissolve it).

Biochemistry

What is the easiest way to identify a molecule as “organic”? Organic means “contains carbon” 90% of all know compounds are organic

Define functional group: a group of atoms in a chemical that defines its characteristics

Define the following root words:

Macro: “big,large"

Mono: “one”

Poly: “many”

CARBOHYDRATES

• Made of: C, H, O (ratio of 1:2:1)

• Monomer (Subunit): monosaccharide

• Function: to provide energy for the body 3 sizes:

Monosaccharide

• Smallest Carbohydrate

• Glucose, Fructose, and Galactose are 3 monosaccharides

Disaccharide

• Two monosaccharides bonded together

• Sucrose Lactose Maltose are 3 important disaccharides: (these all make up sugary foods)

Polysaccharide

• Many monosaccharides bonded together also called “complex carbohydrates”

• Chain of many highly branched glucose molecules

• Starch Glycogen Cellulose are 3 polysaccharides

“Saccharide” = “sugar” “mono” = “one” “di” = “two” “poly” = “many”

How are the functions of sugars and starches different? Sugar is already in the form needed by the body for metabolism, so it doesn't need to be digested – it only needs to be absorbed. On the other hand, starch does require digestion, as it must be broken down into sugar in order to be absorbed.

Lipids

• Elements: C, H, O

• Monomers (subunits): Fatty acid and glycerol

• Ratio: 1:2 for C: H, and much less oxygen

  -Example: C50: H100: O6 (about twice as much H as C) (Does NOT have 1:2:1 C: H:O ratio like carbohydrates)

• Hydrophobic: means that they do not dissolve in water

5 Types of Lipids:

• Unsaturated Fats (Oils)

• Saturated Fats

• Waxes

• Steroids

• Phospholipids

Proteins:

• Made of: C, H, O, N

• Subunit: Amino acids

• Primary functions of proteins: Help the growth and maintenance of cells

Monomer: Amino Acid (also known as a peptide)

Polymer: Protein (also known as a polypeptide or amino acid chain)

The table below are some protein examples:

The effect of temperature on proteins:

• As temperature rises, this affects the stability of the hydrogen bonds that are holding the secondary and tertiary structures in place.

• The result of an increase in temperature could be denaturation or unraveling of the protein to the primary structure.  If this occurs, the protein loses its ability to properly function within the body.

The table below displays the different protein structures

Enzyme:

• Function: speed up the rate of reactions

• Enzyme: The specific protein responsible for breaking down/building  a reactant in a living thing

• Substrate(s): The reactant in a chemical reaction performed by an enzyme

• Active Site: The physical place on the enzyme that the substrate molecule fits into

• Enzyme-Substrate Complex:  The single structure formed when an enzyme is completely bonded to the substrate, before the substrate(s) change into the product(s)

• Product(s): The resulting molecules that are formed in a chemical reaction (released from the enzyme)

How do enzymes generally work?

• Enzymes use the processes of dehydration synthesis and hydrolysis to preform their reactions

Note: In the pictures above, an arrow with the word “enzyme” above the blue arrow indicates that the enzyme is the molecule that turns the reactants into the products.