Ch 2 Test Review Flashcards
Major subatomic particles of an atom
Protons- positive
Neutron- neutral
Electrons- negative
Atomic number
The number of protons an atom possesses
Gives the atom its identity/ physical properties
Mass number
Number of protons and neutrons
Isotopes
Atoms having the same atomic # but different mass #
Which particles determine the chemical properties of an atom
The number of electrons in the valence shell
Why are atoms always electrically neutral?
They have the same number of protons and neutrons which cancel each other out
What are ions?
Atom or molecule that has lost or gained an electron
Valence shell
Outermost shell, participates in bonding
Octet rule says that atoms will gain, lose or share electrons so as to have eight electrons in their valence shell, achieving stability
Noble gases
Have fully satisfied valence sheds and are nonreactive
4 most abundant elements in the human body
Oxygen
Carbon
Hydrogen
Nitrogen
3 basic types of mixtures
Suspensions
Colloids
Solutions
Suspensions
Consists of a liquid mixed with a solid
Solids usually visible
Particles will settle out if left alone
Colloids
Appear opaque but particles are small enough that they cannot be seen with the naked eye.
Particles will not settle out
Solutions
Consists of a solid, liquid or gas mixer with a liquid (usually water)
Usually translucent because one substance dissolved in another
Types of chemical bonds
Ionic bonds
Covalent bonds (polar and non polar)
Hydrogen bonds
Ionic bonds
Complete transfer of electrons between a metal and a non metal
Covalent bonds
Bonds that involve the sharing of electron pairs between atoms
Single, double, triple bonds
Nonpolar covalent bond
Involve equal sharing of electrons because atoms involved in the bond have equal pull for the electrons
Polar bonds
Involve unequal sharing of electrons because one of the atoms involved in the bond has a stronger pull on the electrons than the other
Form polar molecules like water
Hydrogen bonds
Weak bonds based on electrical attractions between molecules
Activation energy
Minimum amount of energy required to start a chemical reaction
Endergonic reactions
Require an input of energy that is greater than the reactants
Require chemical, electrical or mechanical energy from another source to proceed
Products contain more energy than the reactants
Exergonic reactions
Reactants have more energy than is needed
Excess energy stored in the reactants is released leaving the product with less energy than the reactants
Enzymes
Speed up chemical reactions by lowering the activation energy
Highly specific for individual substrates
Do not alter the chemical reactions
Organic compounds
Those that contain carbon bonded to hydrogen
Carbohydrates
Proteins
Lipids
Nuclei acids
Inorganic compounds
Generally do not contain carbon bonded to hydrogen
Water Acids Salts Bases CO2, oxygen
Acid
Hydrogen ion donor
Lower pH
Base
Hydrogen ion acceptor
Higher pH
Monosaccharides
Single sugar molecules
Monomers of carbohydrates
Glucose, fructose, galactose
Disaccharides
Two sugar molecules
Simple sugars
Sucrose, lactose, maltose
Polysaccharides
Many sugar molecules
Starch, glycogen
Main function of carbohydrates
Fuel
Lipids
Mainly hydrophobic molecules such as fats and oils
Glycerides
Steroids
Phospholipids and glycolipids
Most common form of fat in the body
Triglycerides
Triglycerides
Three fatty acids attached to a glycerol molecule
Saturated fatty acid
Found primarily in animal fats and mostly solid at room temp
Unsaturated fatty acid
Lower melting point and generally liquid at room temp
Hydrophobic
Water hating
Hydrophilic
Water loving
Phospholipids
Glycerol backbone, two fatty acids and a phosphate group
Hydrophilic phosphate Head
Hydrophobic fatty acid tail
What are the monomers of proteins?
Amino acids
Structure of an amino acid
Central Carbon, hydrogen, oxygen and nitrogen
Primary protein structure
Amino acid sequence of its polypeptide- all amino acids held together by covalent bonds
Secondary protein structure
Alpha helix and beta pleated sheets
Polypeptides folding over one or more segments on themselves
Tertiary protein structure
Refers to the 3D shape that is assumes
Twists, folds, coils that form around the alpha helices and beta pleated sheets
Shape is stabilized by hydrogen bonds
Quaternary protein structure
Many Proteins consist of more than one polypeptide chain and this is the manner in which the polypeptide chains assemble
Nucleic acids
Genetic material composed of nucleotides
Nucleotides
Monomers of nucleic acids found in the central core of the cell
ATP is our main source of chemical energy
Types of nucleic acids
DNA and RNA
DNA
Contains the sugar deoxyribose
Contains the nitrogenous based adenine, guanine, thymine, and cytosine
The two strands are held together by hydrogen bonds
RNA
Consists of only one single strand of nucleotides and is not confined to the nucleus.
Contains the nitrogenous base uracil instead of thymine
Function of ATP
Body’s main source of energy present in amino bonds
High energy compound
