Chapter2 Flashcards
anything that has mass and occupies space
matter
states include:
- solid
- liquid
- gas
capacity to do work or put matter into motion
energy
types : kinetic and potential
forms of energy
- chemical energy-stored in bonds of chemical substances
- electrical energy-results from movement of charged particles
- mechanical energy- directly involved in moving matter
- electromagnetic energy- exhibits wavelike properties
elements about 96% of body mass
oxygen. carbon, hydrogen, nitrogen
about 3.9% of body mass
Ca, P, K, S, Na, Cl. Mg, I, Fe
trace elements of teh human body
part of enzymes, Cr, Mn, Zn
current model used by chemists that depicts regions of greatest electron density and predicts chemical behavior of atoms
orbital model
structural variations of elements that differ in the number of neutrons they contain
isotopes
average mass numbers of all isotopes
atomic weight
Except for the first shell which is full with two electrons, atoms interact in a manner to have eight electrons in their outermost__ energy level (_valence_ shell)
octet rule
type of elements that are Stable and _unreactive__
Outermost energy level fully _occupied__ or contains eight electrons
chemicaly inert
- complete transfer of electrons
- seperate ions (charged particles) form
ionic bond
- unequal sharing of electrons
- slight negative charge at one end of molecule, slight positive charge at other end
polar covalent
- equal sharing of electrons
- charge balanced among atoms
nonpolar covalent bond
- attractive force between electropositive hydrogen of one molecule 7 an electronegative atom of another molecule
- common btwn dipoles like water
- also act as intramolecular bonds, holding a large molecule in a 3 dimenstional shape
hydrogen bonds
- synthesis reactions A+B –> AB
- endergoinc reactions -products contain more potential energy than did reactants
anabolic
- decompostition reaction AB–> A+B
- exergonic reactions- release energy
catabolic reactions
_____ are biological catalysts (-ase)
enzymes
- Small, molecules____
- Water, _salts_ , and many acids (HCl) and _bases_ (NaOH)
- Do not contain carbon with some exceptions: CO, _contains carbon but is classified as inorganic
inorganic compounds
- _carbs__, lipids, _proteins___ , and nucleic acids
- Contain _carbon_ , usually large, and are _covalently_ bonded
organic compounds
properties of water
- high heat capacity
- high heat of vaporization
- polar solvent properties
- reactivity/cushioning
- ionic compounds that dissociate in water, and are electrolytes
- Contain _cations_ other than H+ and anions other than OH–
salts
- Both are electrolytes
- _acids_ are proton (hydrogen ion) donors (_acidity_ H+ in solution) HCl H+ + Cl–
- _bases_ are proton acceptors (take up H+ from solution)
NaOH Na+ + OH–
OH– accepts an available proton (H+)
OH– + H+ H2O
acids and bases
[bicarbonate and ammonia are important bases in body]
- Acid solutions contain [H+]
- As [H+] _increases_ , acidity increases
- Alkaline solutions contain bases (e.g., OH–)
- As [H+] decreases_ (or as [OH–] increases), alkalinity increases
acid base concentration
increase [H+], decrease pH
Acidic pH: 0–6.99
pH scale is logarithmic: a pH 5 solution has 10 times more H+ than a pH 6 solution
acidic solutions
decrease [H+], increase pH
Alkaline (basic) pH: 7.01–14
basic solutions
an anabolic process by which two molecules are chemically bonded through the use of enzymes and a loss of water.
- glucose + glucose + enzyme = maltose + water + enzyme.
- The acid group of one
amino acid is bonded to
the amine group of the
next, with loss of a water
molecule.
dehydration synthesis
- a catabolic process by which the bond between monomers are broken by the enzyme and the addition of water.
- Peptide
bonds linking amino
acids together are
broken when water is
added to the bond.
hydrolysis
- Sugars and starches
- Contain C, H, and O [(CH20)n]
- Three classes
- _monosaccharides__
- Disaccharides
- _polysaccharides_
carbohydrates
- functions: major source of cellular fuel
simple sugars containing 3 to 7 C atoms
ex. hexose and pentose sugars
monosaccharides
glucose, fructose, galactose, deoxyribose, ribose
double sugars, too large to pass trhough cell membranes
disaccharides
consists of 2 linked monosaccarides like sucrose, maltose, lactose
polymers of simple sugars, like starch& glycogen/not very soluble
polysaccharides
long branching polymers of linked monosaccharides like glycogen
- Contain C, H, O (less than in _carbohydrates__), and sometimes P
- _insoluble__ in water
Main types:
- Neutral fats or _triglycerides_
- _phospholipids__
- Steroids
- Eicosanoids
Lipids
- neutral fats
- composed of 3 fatty acids bonded to a glycerol molecule
triglycerides
main functions:energy storage, insulation, protection
DNA’s 4 bases
- A, G, C, T
- double stranged helical molecule in the cell nucleus
- provides instructions for protein synthesis
- replicated before cell division, ensuring genetic continuity
RNA’s 4 bases:
A, G, C, U
- single stranded molecule mostly active outside nuclus
- 3 varieties of rna carry out the dna orders for proteins synthesis
- messenger RNA, Transfer RNA, and ribosomal RNA
- Phosphorylation:
- _terminal_ phosphates are enzymatically transferred to and energize other molecules
- Such“primed” _molecules_ perform cellular__ work (life processes) using the phosphate__ bond energy
function of ATP
