Chapter 3 Flashcards
Carbon and Organic Molecules
- organic molecules contain carbon(significant amount, not CO or CO2)
- atomic number is 6
- first shell has 2 electrons second cell has 4
- carbon is versatile
Carbon is…
- versatile, meaning it can form 4 bonds with other substances
- 4 electrons in the outer shell
- needs 4 electrons to fill the out shell (to make an octet)
- makes up to 4 bonds, can be polar or nonpolar
- polar molecules dissolve more readily in water, water is polar
- Big idea Carbon is the backbone of all of these molecules because of its versatility, it can form single bonds, doubles or triple bonds.
The Carbon atom
-C-C and C-H bonds are nonpolar
-Oxygen- high electronegativity, so C-O bonds are polar
-polarity has to do with differences in electronegativity, if one atom is a bigger electron charge hogger then they get a charge
- they are equal sharing of electrons
oxygen is a big electron hog, so it has a high electronegativity
Carbon bonds; stability
- bonds are stable within a large temperature range
- organisms can exist within a large temperature range
- molecules in our body don’t fall apart because it is cold or hot, they remain integrated
Hydrocarbons
- molecules predominately made of H-C bonds
- they are hydrophobic and poorly soluble in water
- the design of the organic molecule is C’s using all 4 of its bonds, to bond with H
- lines represent covalent bonds
- carbons are saturated with H’s around them
functional groups
- define the function of the organic molecule
- with certain characteristic properties
- groups of atoms that come up over and over again in different biological functions
- R means that there is other stuff over here
- big idea is that we take our basic organic hydrocarbon and we modify them by adding different groups, these different groups have different chemical properties and they behave differently
bees wax vs. sugar cube
- both are made of very long hydrocarbon chains, but what makes their properties so different is which functional group they have
- the sugar is hydrophilic because it dissolves easily in water
- honey is a lipid that doesn’t interact with water
isomers
- identical molecular formulas, different structures
- molecular formula tells us that atoms that make up a moelcule but doesn’t say exactly how those atoms are put together
- isomers are where the molecular formulas are the same but the structure is different
- example: 2 cats, both made of the same parts, but they are put together differently
- we know the atoms we just don’t know the arrangements
molecular formula
tells us the atoms that make up a molecule but doesn’t say exactly how those atoms were put together
structural isomers
- same atoms, different bonding relationship
- difference is just the arrangement
- example: propanone and propanal, differ by the placement of the methyl group
stereoisomer
- same atoms, same bonding relationship, but different spatial arrangement
- same atoms, similar bonding but just different in 3D space
- cis-trans
- enantiomers
cis-trans isomers
- positioning around DB
- cis is on the same side
- trans is on opposite sides
enantiomers
-mirror images
Stereoisomer (cis, trans) : retinal example
- Retinal- made from vitamin A, carrots help produce this
- you have a situation in order to become active form, light comes in and hits molecules in the back of the eye and changes it from trans to cis
- same atoms, same bonding arrangement just changes from cis to trans and now sets up a reaction for you to process what you are seeing
Stereoisomer(enantiomers): Thalidomide example
- thalidomide- sedative commonly used in 1957
- mirror images
- comes in 2 forms, R and S thalidomide
- common drug given to pregnant women, solution contained both isomers of thalidomide
- R version is the one that helps sleep, S version is very similar but caused a bunch of birth defects
- babies born to mothers who took this had almost no limbs
- malformations in the embryonic period were caused by the S thalidomide
- teratogenicity- harmful to embryo or fetus
macromolecules
- large, complex organic molecules
- thousands or millions of atoms
- looks at a stretch of DNA, not just a bunch of different atoms but together a bunch of regular sized molecules put together
- double helix forms the DNA in our body and made up of backbone of sugars, phosphates and nucleotide bases
- monomers are subunits of polymers
When the monomer is a monosaccharide (glucose, fructose)….
the polymer is a polysaccharide (starch, glycogen, cellulose)
When the monomer is an amino acid (arginine, leucine)…
the polymer is.. a polypeptide or protein (A and B chains of insulin are polypeptides and insulin is a protein)
when the monomer is a nucleotide (sugar, phosphate, base in combination)
the polymer is a nucleic acid (DNA and RNA)
macromolecule formation: condensation and dehydration
-polymers are made via condensation
- monomers “condense” into a polymer
-link monomers to form polymers
-dehydration reactions- type of condensation reaction
- 2 monomers and condense into a single long molecule
it releases water as the byproduct in the reaction
-instead of two monosaccrides we now have 2 disacchride
monosaccharides
- these are the simplest sugars
- different structures-linear or ring
- can join together by dehydration and form a larger carbohydrate
- one sugar, taste sweet
- structure: 6 C’s in a row with H and OH except C 3 is OH and H
- D-glucose
- usually 5 or 6 carbons
starch
- complex carbohydrate in nature
- what plants use to sore energy
- each circle is a glucose moelcule linked together, as you add another glucose moelcule, each is a dehydration reaction
- started with a monomer glucose and we get a big complex polymer, starch
disaccharides
- monosaccharide joined by a condensation or dehydration reaction (byproduct is water)
- form glycosidic bonds- bond formed between two monosaccharides
- broken apart by hydrolysis
- examples: sucrose(sugar cubes- 2 mono combined) , lactose(2 disaccharides, galactose and glucose together)
- lactose in tolerant, you lack enzyme to properly break lactose down into 2 monosaccharides
polysaccharide
- many sugars are made
- large polymers
- example: energy storage: starch, glycogen
- plants store extra chemical energy in form of starch in bodies, plants use glucose
- we use them in structural in animal bodies where we have an exoskeleton, outer shell is exoskeleton that is made of chitin
- structural: cellulose, chitin
- bunch of simple sugars together
macromolecule formation: Hydrolysis
- cleavage of polymers by water
- H+ attaches to the polymer, OH- attaches to the monomer
- it is the reverse reaction
- water comes in and breaks it
triglyceride
- main way we store fat
- we store it in fat cells
- sometimes we lose weight, a lot of hydrolysis goes into play, you have to break down and burn them for energy
- eat you, make triglycerides and stores it
- when u lose weight, hydrolysis takes the triglycerides out of storage and breaks them apart
Carbohydrate
- contain C, H and O
-Cn(H2O)n
most carbon atoms are linked to a H or OH
-sugars, simple and complex sugars
-breads, pastas and crackers
-D- glucose is C6H12O6
-number of different isomers of glucose- same atoms put together in slightly different way
-6 C’s down the middle, H and OH on opposite sides
except for C3, it is OH and H
Monosaccharide: pentose
5 carbon sugar
- carbohydrates are made of 5 carbons
- fructose**
Monosaccharide: Hexose
- 6 carbon sugar
- glucose
glycosidic bond
it is a bond formed between two monosaccharides to make a disaccharide
Polysaccharides and Energy storage: starch and glycogen
- starch (plants) glycogen (animals and fungi)
- different in branching pattern
- starch and glycogen and both polymers of glucose
- amylopectin and amylose are both part of starch
- glycogen is highly branched, amylopectin moderately branched and amylose is not branched
- all made from same stuff just constructed differently
Starch: Structure
- helical structure(spiral shape)
- amylose- simplest
- amylopectin- more complex
- not water soluble
- moderately branched, not very compact
- properties- C, H and O - very stable
- form storage of energy and glucose for plants