Chapter 2 Flashcards
element
simplest form of matter to have unique chemical properties
atomic number
number of protons in its nucleus
How many elements have biological roles?
24 elements
minerals (2)
- inorganic elements extracted from soil by plants & passed up the food chain to humans
- constitute 4% of body weight
What are electrolytes (mineral salts) needed for?
nerve & muscle function
Electrons determine the ______ properties of atoms
chemical
isotopes
elements that differ from one another due to the number of neutrons
atomic weight (2)
- relative atomic mass
- accounts for the fact that an element is a mixture of it s isotopes
radioisotopes
unstable isotopes that give off radiation
radioactivity
radioisotopes decay to stabilize isotopes by releasing radiation
Who was the first woman to receive a Nobel Prize?
Madame Curie
What happens when an atom is converted into an ion?
high energy radiation ejects electrons from atoms
ions
charged particles with unequal number of protons & electrons
ionization
transfer of electrons from one atom to another
anion
atom that gains electrons (-charge)
cation
atom that loses and electron (+ charge)
electrolytes
- salts that ionize in water & form solutions
- can conduct an electric current
What is one of the most important considerations in patient care?
electrolytes
free radicals (2)
- chemical particles with an odd number of electrons
- produced by normal metabolic reactions
What do free radicals cause?
tissue damage
antioxidants
neutralize free radicals
molecules
chemical particles composed of 2 or more atoms united by a chemical bond
compound
made up of molecules with 2 or more different elements
isomers
molecules with identical molecular formulas, but different arrangements
What the types of chemical bonds?
- ionic
- covalent
- hydrogen
- van der waals forces
single vs double covalent bonds
single: one pair of electrons shared
double: two pairs of electrons are shared
nonpolar covalent bonds
electrons shared equally
polar covalent bonds
electrons shared unequally
hydrogen bonds
a weak attraction between a slightly positive hydrogen atom and a slight negative atom
Are water molecules weak/strongly attracted to one another?
weakly
Van der waals forces (2)
- weak brief attractions between neutral atoms
- only 1% as strong as covalent bonds
mixtures
consist of substances physically not chemically blended
Properties of water (5)
- universal solvent
- cohesion (surface tension)
- adhesion
- chemical reactivity (hydrolysis & dehydration)
- thermal stability (high heat capacity)
hydrolysis (2)
- water used to break bonds
- breaks covalent bonds
dehydration
water released when bonds are made
solution
consists of a solute & solvent
colloids (6)
- can change from liquid to gel state within & between cells
- in the body they are mixtures of protein & water
- small particles
- too large to pass thru semipermeable membrane
- remain permanently mixed with the solvent when left alone
- cloudy
suspension (4)
- large particles
- too large to penetrate selectively permeable membranes
- separates when left alone
- cloudy
emulsion
suspension of one liquid in another
in a percentage (concentration) (2)
- # of molecules unequal
- weight of solute equal
in molar (concentration) (2)
- # of molecules equal
- weight of solute unequal
acid
proton donor (release H+)
base
proton acceptor (accept H+)
pH
measurement of H+ on a log scale
What does our body use to resist changes in pH?
buffer
energy
capacity to do work
potential energy (2)
- energy contained in an object b/c of its position or internal state
- not doing work
kinetic energy (2) & example
- energy in motion
- energy that is actively doing work
ex. heat
decomposition reactions(3)
- large molecule breaks down into 2 or more smaller ones
- AB-> A+B
- break
classes of chemical reactions (3)
- decomposition
- synthesis
- exchange
free energy
potential energy available in a system to do useful work
synthesis reactions (3)
- two or more small molecules combine to form a larger one
- A+B->AB
- create
exchange reactions
- two molecules exchange atoms or group of atoms
- create & make
reaction rates affected by (3)
- concentration of reactants
- temperature
- catalysts
catalysts (3)
- substances that temporarily bind to reactants
- speed up reactions
- not permanently consumed or changed
catabolism (3)
- exgeronic
- breaks covalent bonds
- decomposition
anabolism (4)
- endergonic
- require energy input
- synthesis
- driven by energy that catabolism releases
Catabolism & anabolism are _______ linked
inseparately
oxidation (2)
- molecules give up electrons & releases energy
- reducing agent
reduction (2)
- molecule that gains electrons & energy
- oxidizing agent
4 categories of carbon compounds
- carbohydrates (sugar)
- lipids (fat)
- protein
- nucleotides
Characteristics of Carbon (3)
- has 4 valence electrons
- bind readily with each other to form a carbon backbone
- neutral backbone carries a variety of functional group
macromolecules
very large organic molecules
polymers/polymerization
made up of repetitive monomers
monomers
identical or smaller subunits
carbohydrates (4)
hydrophilic
CH2O
converted into glucose
oxidized to make ATP
3 important monosaccharides
glucose, fructose, galactose
What type of sugar is glucose?
blood sugar
3 important disaccharides
sucrose, maltose, lactose
3 polysaccharides in Humans
glycogen, starch, cellulose
What is the purpose of glycogen?
energy storage of polysaccharides in animals
What is the purpose of starch?
energy storage in plants
What is the purpose of cellulose in plants?humans?
structural molecule of plant cell walls; fiber in our diet (helps move materials through intestine)
conjugated carbohydrates
covalently bond to lipid or protein
What conjugated carbs are apart of the external cell surface coat?
glycoproteins & glycolipids
purpose of proteoglycan? (2)
cell adhesion
lubrication
5 primary types of lipids in humans
triglycerides steriods eicosaniods fatty acids phospholipids
Lipids (2)
hydrophobic
less oxidized than carbs
What type of fat are triglycercides?
neutral fat
structure of triglycerides
3 fatty acids covalently bond to glycerol
triglycerides when liquid___, when solid____
oil; fat
primary function of triglycerides? (3)
energy storage
insulation
shock absorption
fatty acid (2)
- chain of 4 to 24 carbon atoms
- contain a carboxyl group on one end and methyl group on the other
saturated fatty acids vs. unsaturated fatty acid
saturated: carbon atom saturated with hydrogen
unsaturated: contains C=C bonds
What types of fats can not be synthesized by the body?
essential fatty acids
phospholipid
similar to neutral fat, but 1 fatty acid is replaced by phosphate group
eicosaniods
chemical messenger between cells
cholesterol (2)
- “parent” steroid from which other steroids are synthesized
- synthesized only by animals
which is the good/bad cholesterol?
good: HDL (lower ratio of lipids to proteins)
bad: LDL (high ratio of lipids to proteins)
peptide
2 or more amino acids
what causes a protein to denature?
extreme heat or pH
the different structures of proteins are held together by what type of bonds?
hydrogen bonds
non amino acid moiety of a conjugated protein?
prosthetic group
what are the functions of proteins? (7)
structure communication membrane transport catalysis recognition & protection movement celladhesion
enzymes (3)
- lower activation energy
- biological catalyst
- break covalent bonds between monomers in substrate
cofactor vs coenzyme
cofactor: inorganic; induce a change in enzyme shape to activate active site
coenzyme: organic; accept electrons from an enzyme and transfer to another enzyme
3 components of nucleotides
nitrogenous base
sugar
1 or more phosphate groups
ATP components
adenine (nitrogenous base)
ribose (sugar)
phosphate groups (3)
Where does ATP hold its energy
in covalent bonds
Other types of nucleotides?
GTP
cAMP
