Biochem: Chemical and physical foundations Flashcards
Length of a single bond of 2 carbon atoms
0.154 nm
Length of a double bond of 2 carbon atoms
0.134 nm
Structures formed by carbon atoms
Linear chains (Methyl) , branched chains (Enol), and cyclic structures (carbohydrates, Phenyl)
The simplest functional group
1. methyl
2. ethyl
3. carbonyl
4. carboxyl
Methyl
R-C-H3
what are the most common functional groups
- Methyl - single carbon linked to 3 hydrogen atoms and one R group
- Ethyl - 2 carbons connected in a single bond, connected to 5 hydrogen atoms and R group
- Phenyl - benzene ring with 1 R group
- Aldehyd - C double bonded to O, single bond with 1 H and 1 R group
- Keton - double bond of C=O with 2 R groups
- C in double bond with O and single bond with O- and R
- Hydroxyl (alcohol) R-OH
- Enol - C=C with 2 H on one C and OH, R single bonded with the other C)
- Ether - O connected to 2 R groups (like ketone without C)
- Ester - O single bonded to R and C, C double bonded to O and single bonded to R (carboxyl with extra R connected to O)
- Acetyl - R-O C double bond to O and single bond to C single bonds with 3 H
- Anhydride - 2 carboxyl groups
- Amine - N+ connected to 3 H and 1 R
- Amide - NH2 connected to C with double bond to O and single bond to R
- Imine - HN with double bond to C with 2 R groups (HN = C - 2R)
- Sulfhydryl - R-S-H
- Disulphide - R -S-S-R
- Thioester - R-C(=O) - S- R
- Phosphoanhydride - 2 x PO3R connected by single bond to O
What are cis-trans isomers?
Isomers that differ in the arrangement of their substituent groups with respect to the nonrotating double bond (Latin cis, “on this side” - groups on the same side of the double bond; trans, “across” - groups on opposite sides)
What is the relationship between malate and fumarate?
malate is the cis isomer and fumarate is the trans isomer
What are asymmetric carbons in a molecule called?
Chiral centres
Formula for calculating number of possible stereoisomers
2^n with n = number of coral centres
First law of thermodynamics
in any physical or chemical change, the total amount of energy in the universe remains constant, although the form of the energy may change –> energy cant be created or destroyed
Second law of thermodynamics
the total entropy of the universe is continually increasing
Formula for Gibb’s free energy G
G = dH - TdS
When will a process occur spontaneously?
when G is negative (dH is negative when heat is released, and S is positive when randomness increases)
Why is breaking ATP considered the universal energy source of the body?
The reaction of ATP –> ADP + Pi or AMP + PPi are highly exergonic (dG is negative), this allows the body to commit endergonic reactions through completion, because the sum of dG remains negative.
