Human Anatomy and Physiology 1 (MATC) Lecture Exam 1

covalent bond

multiple atoms combined to fill the valence shells

molecule

two or more atoms held together by covalent bonds

ionic bond

when atoms in a molecule have charges (different number of protons and electrons). attraction of a pos./neg. ion.

chemical reactions

the making and breaking of chemical bonds, leading to changes in the composition of matter. generally reversible.

hydrogen bond

weak attraction between a hydrogen atom and another atom.

ex: H20 - so many protons in O, H's electrons spend more time with O so O takes on a negative charge and H takes on a positive charge - more so between molecules than atoms

ions

charged particle (atom or molecule).

dehydration reaction

formation of large molecules (polymer) by the removal of water

monomer

small chemical unit that makes up a polymer

hydrolysis

A chemical process that splits a molecule by adding water. (breaking of a covalent bond through an enzyme)

macromolecules: carbohydrates

monomers of carbs are simple sugars.
monosaccharide - one sugar
Glucose: C6H12O6 1:2:1 ration

starch: where does it store? what does it store?

store glucose in plants

glycogen: where does it store? what does it store?

store glucose in animals
polymer of glucose
stored in liver and muscles, in blood for a ready supply

macromolecules: PROTEINS - what are their monomers? what are they when hydrogen comes off in water?

amino acids are monomers
(small molecules) they are acids.

acids:

substances that release hydrogen ions when dissolved in water, leaves electron behind.

components of protein

carbon, hydrogen, oxygen, nitrogen

The sulfur-containing amino acids (cysteine and methionine) are generally considered to be

nonpolar and hydrophobic

All amino acids contain an amino(-NH2) group(bonded to the Alpha-Carbon), which contains Nitrogen.

However, there are some Amino Acids, including Lysine, Arginine, Histidine, which contain more Nitrogen than the others

amino acids, which are small organic molecules that consist of an

alpha (central) carbon atom linked to an amino group, a carboxyl group, a hydrogen atom, and a variable component called a side chain. The largest group of amino acids have nonpolar side chains.

carboxyl group

A functional group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group. (-COOH)

amino group

A functional group that consists of a nitrogen atom bonded to two hydrogen atoms (-NH2)

Hydroxyl

OH-
R means variable group

amino acids are ___ (charge) and have a ________ because of one ____ side and one ____ side

polar. one negative side and one positive side

why is it important to check the polarity of side chains

polar side groups of amino acids form hydrogen bonds

carbons NEED ____ bonds (number)

4

amino group have 2 components

amine group (+)
gain electron (-)

always nonpolar

amine group

the nitrogen-containing portion of an amino acid (NH2)
always nonpolar because of
amine group (+)
gain electron (-)

side chains

the atoms extending beyond the universal H3N+-CH-COO- core of all amino acids and determine their chemical properties

determining side chain polarity

if side chain has a (+) or (-) - polar
sometimes side chains don't have charges - nonpolar

OR

a lot of carbons - nonpolar
many oxygen - polar

side chains are on the___ which are ______ which assemble to make proteins

amino acids, monomers

polypeptides are

polymers of amino acids

polar side chains (+), (-) or many O's can make ____ bonds

hydrogen

polar molecule

a molecule in which one side of the molecule is slightly negative and the opposite side is slightly positive

polymer

large compound formed from combinations of many monomers

amino acids strung together through dehydration rxn

polypeptide bonds

w/ a dipeptide with amino group on one side and acid on the other side

primary structure

sequence of amino acids

secondary structure

Either an alpha helix or beta pleated sheet.

tertiary structure

The third level of protein structure; the overall, three-dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain.

quaternary structure

The fourth level of protein structure; the shape resulting from the association of two or more polypeptide subunits.

polypeptides are

polymers of amino acids

proteins are polypeptides with

more complex 3D structures

polypeptides are polymers of amino acids.

polypeptides are the chain, proteins are the folded 3D shape

how to change a protein

apply heat
remove water
change pH (how many H ions are present)

protein function (1) ENZYMES

catalyze chemical reactions

protein function (2) CELL MEM. CHANNELS

allow materials in or out

protein function (3) CELL RECEPTORS

in membrane or within cell, bind to hormones or other signalers and initiate or stop chemical reactions within the cell

protein function (4) SUBCELLULAR STRUCTURE

organelle membranes, support DNA structure

other functions of protein

support, connective tissue
muscle function
hair and fingernails
energy source

macromolecule: LIPIDS

carbon atoms bonded covalently with hydrogen atoms
C-C
C-H

share equally, no ionization, non polar, hydrophobic

components of lipids

C, H, O
fatty acids, glycerol

fatty acids and glycerol

Building Blocks of Lipids

3 fatty acids and glycerol

fat molecule and 3 H20's after dehydration rxn

fatty acids

chains of carbon atoms bonded to hydrogen atoms

glycerol

A three-carbon alcohol to which fatty acids are covalently bonded to make fats and oils.

Phospholipids

a lipid consisting of a glycerol bound to two fatty acids and a phosphate group.

phosphate group - very polar (philic)
with loads of oxygens - hydrophilic

polar is

hydrophilic

nonpolar is

hydrophobic

lipid characteristics

hydrocarbons - make a chain or ring shape
nonpolar , C-H bonds
easily converted but not much variety
C-C-C-C-C-C-C backbone

lipids are often found bound to

polar molecules such as proteins, glycerol and amino groups.
CANNOT exist without attaching to a polar molecule

lipid functions (5)

cell membrane
steroid hormone
energy storage (adipose tissue)
cushioning (knee joints)
yellow bone marrow

macromolecules: NUCLEIC ACIDS

polymers of monomers. monomers are nucleotides

Nucleotides

Basic units of DNA molecule, composed of a sugar, a phosphate, and one of 4 DNA bases

nitrogenous base

An organic base that contains nitrogen, such as a purine or pyrimidine; a subunit of a nucleotide in DNA and RNA.

DNA nitrogenous bases

Adenine, Thymine, Cytosine, Guanine (AT GC's)

RNA nitrogenous bases

Adenine, Uracil, Guanine, Cytosine (GUAC)

DNA: Good at _____ bonds. ______ because of O and N

Hydrogen Bonds. Polar.

Double Stranded, helix.

RNA is a

single-stranded nucleic acid that passes along genetic messages

how to count 5 carbons

5' at top, go counterclockwise, 4,3,2,1

Function of DNA: DNA replication

store genetic information. unzip, expose nitrogenous bases, formation of 2 strands

. DNA polymerase

Enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule

DNA replication occurs

ONLY in preparation for cell division.

Nucleic Acid function

storage and transfer of genetic information
ATP - short term energy within a cell adenosine triphosphate

Aqueous environments constitute

45-60% of bodies in plants and animals

Properties of water (5 including acid/base def)

- polar solvent
- hydrogen bonding
-adhesion, cohesion, tension
-thermal stability
-acid/base, pH
- proton donor (acid)
- proton acceptor (base)

water resists heating and ____ (2)

hold heat well, insulates well

solution

A homogeneous mixture of solute and solvent

solute

Substance being dissolved

solvent

substance that does the dissolving

salt

An ionic compound made from the neutralization of an acid with a base. ( research more )

colloid

A mixture containing small, undissolved particles that do not settle out.
ex: flour in water

emulsion

any mixture of two or more immiscible liquids in which one liquid is dispersed in the other
ex: oil/water

suspension

A mixture in which particles can be seen and easily separated by settling or filtration. cloudier than a colloid

most fundamental acid base rxn is the

dissociation of water

H20 -- H+ + OH-

[ ] means

concentration

highest pH

14

lowest pH

1

pH of pure water

7 (neutral)

strong acid

ionize freely, easily give up H+

weak acid

ionizes slightly, keeps H+ bond

strong base

strongly binds H+

weak base

weakly binds H+

buffer

A chemical substance that resists changes in pH by accepting hydrogen ions from or donating hydrogen ions to solutions - weakening acids and bases

pertaining to nucleic acids: gene

sequence of DNA nucleotides that determines the order of amino acids in a polypeptide

pertaining to nucleic acids: locus

location of a chromosome where a gene is found

pertaining to nucleic acids: pyrimidine base

single ringed, thymine, cytosine, uracil

pertaining to nucleic acids: purine base

double ringed, adenine and guanine

Transcription

specific part of a DNA molecule unzipped and RNA nucleotides are added by RNA polymerase. RNA transcript is then processed - complementary bases, not a copt

DNA --> RNA what does the arrow represent

the flow of information. Guided by the DNA "blueprint", transcribed by RNA. no chemical changes. the process is transcription.

DNA to primary RNA to mRNA

see notes page 21

DNA contains information for ____ to make ______ --> Proteins

for amino acids to make polypeptides ---> proteins

the genetic code

collection of codons of mRNA, each of which directs the incorporation of a particular amino acid into a protein during protein synthesis

universal to all living things

codon

A specific sequence of three adjacent bases on a strand of DNA or RNA that provides genetic code information for a particular amino acid