Chapter 2 Flashcards
Smallest component of a pure substance
Atom
Interacting atoms (chem bonds) form this, make up living cells
Molecules
Science of interactions between atoms and molecules
Chemistry
Atomic # is = to
Proton #
Atomic weight is = to
P# + N#
Atoms w identical # of protons, all behave the same way
Element
A molecule w at least 2 different kinds of atoms
Compound
The 13 major elements of living organisms
C. HOPKINS Mg CaFe (loves) Na
Charlie Hopkins manages a cafe, loves salt
Atoms have gained or lost electrons, the attraction between opposite charges is known as
An ionic bond
Sharing of electrons is what kind of bond
Covalent
A hydrogen atom that is bonded covalently to an I or O, is attracted to another O or N
Hydrogen bond
Define an acid
Dissociates into one of more H+ ions and one or more neg ions
H+ donor
Define a base
Dissociates into 1 or more pos ions, plus one or more OH-
The pH scale measures
The amount of H+ in a solution
Dissociates in water into cations and anions, doesn’t give H or OH
Salt
NaCl—h2o—> Na + Cl
Compounds that help keep pH from drastically changing
pH buffers
Part synthesis, part decomposition reaction
Exchange reaction
Building blocks of carbohydrates
Simple sugars ( monosaccharides)
Role of carbohydrates
Major source of energy in living organisms, fuels cell activity (make ATP). Some sugars needed for cell walls
Structure of simple lipids
3 fatty acids and a glycerol
Role of lipids
Make up plasma membranes, energy storage (Fat)
Building blocks of proteins
Amino acids
Structural proteins
Make up basic structures (muscles)
Functional proteins
Facilitate metabolic processes (enzymes)
Primary protein structure
Strand of amino acids, peptide bonds “polypeptide strand”
Secondary protein structure
Polypeptide strand curls becoming double helix, or pleated sheets, H bonds added
Tertiary protein structure
Combo of primary and secondary, 3D structure, catalyze reactions, interactions between various side groups (ex : hydrophobic interaction w nonpolar side groups)
Quaternary protein structure
More than 1 tertiary structure. Several folded polypeptide chains (2or more)
Role of nucleic acids
Store genetic info, form atp and other energy carriers
Building blocks of nucleic acids
Nucleotides
What makes up a nucleotide
A nitrogen-containing base, a pentose (5-carbon sugar, deoxyribose or ribose), a phosphate group
The nucleus bears an overall _____ charge
Positive (Bc it’s made up of protons and neutrons)
Opposite charges _____ each other (repel or attract)
Attract
Isotopes of an element have the same number of ____ in nucleus, but different number of ______
Different number of neutrons
Same number of protons
(Same atomic #, different Atomic weight )
16
C
8
What each number represents
16= weight 8= atomic #
The 4th 5th and 6th electron shells can hold how many electrons
18
The inner most electron shell can can hold
The 2nd and 3rd can hold
2
8
Why atoms want the outer most electron shell filled
Chemically Stable
What an atoms valence number means
Number of extra or missing electrons in outermost electron shell
Extra meaning to become stable should lose, missing meaning empty shells only needs a couple more to become stable
A negatively or positively charged atom (gained or lost electrons) is called
An ion
The strongest and most common type of bond
Covalent
In an H2O molecule, the e tend to be closest to which nucleus
Oxygen
The O in H2O has a slightly _____ charge
Negative charge (Bc e tend to be closer to O nucleus)
2 elements most frequently involved in hydrogen bonding
Oxygen and nitrogen
Weaker versions of these bonds are important in antigen-antibody reactions
Ionic
What is a biochemical reaction
Chemical reaction in a living system
What pH stands for
Potential hydrogen
Each number represents a _____ fold change in concentration
10 fold ( ph of 1 has 10 x more H ions than 2, 100x more than 3 )
How to calculate pH of a solution
-log [ H*]
Most organisms grow best in environments w a ph of
6.5-8.5
When a water molecule is released after a reaction it is called
Dehydration synthesis (or condensation reaction)
Deoxyribose is a _____ that is used in DNA
Sugar (carbohydrate) (pentose)
Examples of monosaccharides (a kind of carbohydrate)
Tetrose (4-carbon sugar), pentode (5-carbon sugar), etc
When 2 monosaccharides bond in a dehydration synthesis
Disaccharides
Disaccharides can be broken down via this reaction
Hydrolysis ( add water)
Ratio of hydrogen to oxygen in carbs
2:1
Lipids are (polar or nonpolar)
Non : don’t have positive and negative end, insoluble in water
Structure of a fatty acid
Long hydrocarbon (just h and c) chains ending in a carboxyl group -cooh
What makes up a glycerol
3C atoms, 3 hydroxyl groups (-oh)
The number of fatty acid molecules determine if lipid is
Monoglyceride, diglyceride, or tri
Difference between saturated and non saturated fatty acid
Saturated- no double bonds (become solid more easily)
Un- double bonds, create kinks
Structure of complex lipids
A glycerol, 2 fatty acids, and a phosphate group
Complex lipids are also called
Phospholipids
To create a phospholipid bilayer (plasma membrane) phospholipid molecules turn themselves so that
Polar (hydrophilic) parts face water molecules, nonpolar ends (hydrophobic) face inwards
The polar potion of a phospholipid
The nonpolar portion
Polar- phosphate group & glycerol
Non- fatty acid
Enzymes are what kind of macromolecule
Protein
What makes an amino acid
At least 1 carboxyl group
(-COOH), one amino group
(-NH2), an alpha carbon (in center) , an R group
Difference between A G nucleotides and T C U
AG- double ringed structure (a purine)
T C U- single ringed (pyrimidine)
As ph increases, what increases
OH concentration (more acidic =more H, more basic = more OH)
_____ do best in acidic conditions
_____ do best in alkaline
Fungi
Cyanobacteria (prokaryotes)
What makes polysaccharides different from mono and disaccharides
Lack sweetness, usually not soluble in water
Chitin (of a fungal cell wall) is made of
Polysaccharides
Living cells are mostly composed of
Proteins
Other functions of proteins besides functional and structural
Integral parts of cell structures, hormones (regulatory functions)
For every peptide bond formed between amino acids, ___ is released
H2O (dehydration synthesis)
A polypeptide refers to how many amino acids peptide bound
10-2000
