Chapter 2: Chemistry Flashcards
Element
Is a substance that cannot be broken down chemically into any other substances
Atoms
Is a bit of matter that cannot be subdivided any further without losing its essential properties
Protons
Are particles that have a positive electrical charge
Neutrons
Are particles that have no electrical charge
Electrons
Negatively charged particles floating around the nucleus
Atomic Mass
Is made up of the combined mass of all of its protons and neutrons
Atomic Number
Corresponds to the number of protons an element has
Isotopes
Atoms with the same number or protons but a different number of neutrons
Big 4 Elements in Humans
Oxygen, carbon, hydrogen, nitrogen
Electron Shells
Electrons move around the nucleus in designated areas
1st Electron Shell
Can hold 2 electrons
2nd Electron Shell
Can hold 8 electrons
3rd Electron Shell
Can hold 8 electrons
Atom Stability
Atoms become stable when their outermost shell is filled to capacity
Example of Unstable Atoms
Hydrogen
Example of Stable Atoms
Helium, neon
Ion
An atom that may have an extra electron or lack an electron compared to the amount of protons
Molecule
Groups of atoms held together by bonds
Bond Energy
The amount of energy needed to break a bond between two atoms
Covalent Bonds
When two atoms share electrons.
Simplest example of Covalent Bonds
Two hydrogen bonds forming a hydrogen molecule
Double Bond
The sharing of two pairs of electrons between two atoms
Double bond example
Oxygen
Ionic Bond
Occurs when two oppositely charged ions attract each other. Each electron circles around a single nucleus
Ionic Compound
Ions of two or more elements linked by ionic bonds
Hydrogen Bonds
Is formed between a hydrogen atom in one molecule and another atom.
Water Cohesion
The cohesiveness of water molecules makes it possible for tall trees to exist. Water is pulled up the tree
Waters Large Heat Capacity
Hydrogen bonds are destroyed and formed again somewhere else. The temperature of water doesn’t change much
Waters low density as a solid
When water freezes the density is much lower than other substances. The molecules form a lattice structure which makes it less dense
Water Solvency
Water is able to pull apart ions because water is a polar molecule so it bonds with other ions like sodium chloride to dissolve it
pH
The amount of H+ in a solution is a measure of its acidity
Acid
pH is less than 7. Has more H+ ions
Base
pH is above 7 and has fewer H+ ions
Macromolecule
A large molecule made up from smaller building blocks or subunits
4 types of macromolecules
Carbohydrates, lipids, proteins, and nucleic acids
Carbohydrates
Are molecules that contain carbon, hydrogen, and oxygen. They are the primary fuel for running all of the cellular machinery and much of the structure of cells
What are the simplest form of carbohydrates?
Monosaccharides or simple sugars
Monosaccharides
Contain 3 to 6 carbon atoms and when broken down the products are not carbohydrates
Main types of monosaccharides
Glucose and fructose
Glucose: Fuel for Cellular Activity
Through a series of chemical reactions the relatively high energy bonds in the glucose molecule are converted into lower energy bonds of other molecules
Glucose: Stored Temporarily as Glycogen
Excess glucose can be temporarily stored in various tissues, primarily muscles and liver
Glycogen
The stored glucose molecules are linked together to form a large web of molecules
Glucose: Converted to Fats
Glucose circulating in your bloodstream can be converted into fat a long term energy storage
Disaccharide
When two simple sugars are bonded together
Polysaccharide
Much larger numbers of simple sugars may be joined together
Chitin
Forms the rigid outer skeleton of most insects and crustaceans
Cellulose
Forms a variety of plant structures that are visible around us
Lipids
Are made from atoms of carbon, hydrogen, and oxygen but the atoms are in different proportions
Common characteristics of lipids?
Do not dissolve in water and are greasy. Can be a significant source of energy
Hydrophobic
Molecules that do not interact with water
Hydrophilic
Molecules that readily form hydrogen bonds with water
Glycerol
The head region of a lipid molecule
Fatty Acid
The tail region of the lipid molecule that is linked to the glycerol head
Triglycerides
The fats in most foods. These are fats that have three fatty acids linked to the glycerol molecule
Saturated Fat
If each carbon atom in the hydrocarbon chain of a fatty acid is bonded to two hydrogen atoms
Where are saturated fats found?
Meat and fish
Why are saturated fats bad?
They accumulate in your bloodstream and can narrow the vessel walls that contribute to heart disease and strokes
Unsaturated Fat
Some of the carbon atoms are bound to only a single hydrogen
What has unsaturated fats?
Most plants
Trans Fat
Refers to the unusual orientation of some or all of the double bonds that remain following the addition of hydrogen atoms
What is bad about trans fat?
Causes your body to produce more cholesterol which increases the risk of heart disease
Sterols
Play an important role in regulating growth and development
Cholesterol
Is an important component of most cell membranes. Most is produced in our liver but is also in animals that we eat
Phospholipid
Are the major component of the membrane that surrounds the contents of the cell and controls the flow of chemicals into and out of the cell
Waxes
Resemble fats but have only one long chain fatty acid linked to the glycerol head of the molecule. Strongly hydrophobic because they are non polar
Proteins
Are the chief building blocks of all life. Control the levels of sugar and other chemicals in your bloodstream and carry oxygen through your body
Functions of Proteins
Structure, protection, regulation, contraction, transportation
Enzymes
Initiate and assist every chemical reaction that occurs
Amino Acids
20 different amino acids are strung together and the different combinations result in unique structure and chemical behavior
Primary Structure
The sequence of amino acids in a polypeptide chain, similar to letters spelling a word
Secondary Structure
Corkscrew like twists or folds formed by hydrogen bonds between amino acids in the polypeptide chain
Tertiary Structure
The complex 3D shape formed by multiple twists and bends in the polypeptide chain
Denaturation
The disruption of protein folding
Active Site
Provides a place for the participants in a chemical reaction
Substrate
Is the surface on which an organism lives
Activation Energy
A certain minimum energy is required to initiate the reaction
Nucleic Acids
Macromolecules that store information
Nucleotides
The individual units of nucleic acids
Double Helix
The two spiraling strands of Dna
