Week 3 Flashcards
Cell membrane is a
Phospholipid bilayer
Triglycerides are what functional groups basis
Tri-esters of glycerol with fatty acid chains
How are phospholipids similar to glycerides?O
One fatty acid residues has been replaced with phosphate ester group.
Fatty acids are what functional group?
Long chained carboxylic acids
Which oil saturation is solid at room temp?
Saturated- has no double bonds
Explain how unsaturated fatty acids stay liquid at room temperature.
Plant oils, is a unsaturated bond, meaning it has one double bond with cis configuration. This kink keeps the intermolecular bonds lower, therefore keeping the molecules from “settling in” and keeping it in a liquid state. The decreased amount of intermolecular forces also causes the melting point to be much lower. This keeps linoleum acid (vegetable oil) liquid at room temp
Which type double bonds exist in nature?
Cis
Glycolysis results in
2 pyruvic acid molecules (3 c each) with 2 ATP and 2 NADH
What does pyruvic acid convert to under anaerobic conditions?
Lactic acid. Uses NADH to convert (NADH is the more energetically dense… otherwise sent to electron transport chain to make ATP in aerobic states)
What is pyruvic acid converted to in aerobic conditions?
Acetyl CoA and NADH
How many rounds of Kreb cycle does glucose go through?
2
What does each round of Kreb’s (TCA) cycle produce?
1 ATP. 3 NADH, ONE QH2. So with one molecule of glucose, we get 2ATP net.
What functional group do amino acids consist of?
Amine and carbonyl group
Identity of amino acid is determined by?
Side chain
All amino acids have which chiral family?
L
Carbohydrates we use belong to which chiral family?
D
Can we make amino acids?
No, only change one amino acids to another amino acid
What do enzymes do to the activation energy?
Lowers activation energy but does not influence outcome (favorable or unfavorable)
Michaelis Menten equation
V= Vmax * [s]/ Km + [s]
Km
Substrate concentration when V is half of maximum
What is fructose
Ketose
3 aldoses we need to know are…
Glucose, Mannose, Galactose
Why do you feel the burn?
Local acidosis
Where does glycolysis happen?
Cytoplasm (cytosol)
Where does citric acid cycle happen?
Mitochondria
Where does electron transfer chain happen?
Mitochondria
Citric acid is what kind of pathway?
Amphibolic pathway
REQ
CO2 produced/O2 needed
What does cholesterol do to cell membranes?
Give fluidity
What do double bonds due to fatty acids?
Lower melting point
What do cold water fish have?
Higher omega 6
What do warm water fish have?
Omega 3
Can we convert omega 3 and omega 6?
No, all omega 3 and 6 have to come from diet.
ARACHIDONIC ACID
Common in plasma membrane. Omega 6. Convert to prostaglandin, leukotrienes which are inflammatory.
What does melting point do as fatty acid chain gets longer?
Increases melting point
Linoleic acid
Vegetable oil 18:2 (9,12). Omega 6
Linolenic acid
18:3 (9,12,15) omega 3 vegetable oil
RNA Synthesis is called
Transcription. DNA—> RNA= transcription
mRNA
Copy of blueprint. Reads instructions for synthesis of protein encoded on strand of dna
Protein synthesis is called?
Translation
We make proteins from?
RNA
Where does transcription happen?
In nucleus
Where does translationhappen?
In cytosol
Start of translation?
AUG- methionine
End of translation?
UGA
Transcription factor
Locates genes that needs to be copied
RNAse job?
Degradation of mRNA.
Roll of poly a tail
If we want the mRNA to stick around longer, we need longer tail so it takes RNAse longer to degrade mRNA
Ribosomes
Bind to mRNA to transcribe proteins “walks along mRNA”
What does the mRNA resemble?
DNA coding strand. Except every T is a U on mRNA
Direction of translation?
5’-> 3’
When would proteins be made on rough ER
When you want to secrete cell, use in plasma membrane, or vehicle on cell
When is protein made on free ribosome?
When you want protein in cytosol
TRNA
Brings appropriate amino acids to ribosome during translation. Has anticodon on tip. Acceptor stem carries amino acid
When would you want lots of C’s and G’s in DNA
When you live in boiling environment
Five stages of protein synthesis
1) activation of trans
2) initiation (attachement of ribosome)
3) elongation (3 base pairs of time adding one aa)
4) termination (UGA stop)
5) folding and post translational processing
Ribosomes made out of
RRNA and protein
Which are the negative polar amino acids
Aspartic acid, glutamic acid
What are the positive, polar amino acids?
Arginine, lysine, histidine
What are the uncharged polar amino acids?
Asparagine, glutamine, serine, threonine, tyrosine
What do positive aa have on side chain to make it positive?
N
What do negative amino acids have on side chain to give negative charge?
CooH
Peptide bond forms between
Carboxylic end and amino end to give Cdouble bond O and C-N and n-h
Primary structure of protein
1st protein structure written from translation of RNA
Protein secondary structure
Primary alpha helix or beta pleated sheets from hydrogen interactions within peptide chain
Describe Protein tertiary structure of proteins
INteraction of amino acid side chains
What does a polypeptide chain consist of (what type of bonds?)
Polypeptide chain is amino acids joined by peptide bonds. Joins carboxyl group of one amino acid with amine group of another amino acid
Types of tertiary structure bonds
Disulfide
Salt bridges
Hydrogen bonds
Hydrophobic interactions
Disulfide bonds
Very strong but not very frequent. Very permanent and covalent bonds. THink straight/curly hair, caused by sulfide bonds.
Hydrogen bonds in tertiary structures of proteins
Not terribly strong but there are a LOT of them
Salt bridges
Fairly strong because it is an ionic bond. Not as strong as disulfide.
Hydrophobic interactions in tertiary structure of proteins
In center of protein generally. Non polar side chains interact, outside polar.
Quaternary protein
Assembly of multiple polypeptide chains into an intact, tetrameric protein
What is the only amino acid without chiral structures?
Glycine
How many possible codons?
64
How many amino acids do we have?
20
What combines with acetyl coa to start Krebs cycle?
Oxaloacetate.
When does amino acid behave like cation?
In an acidic solution
When does amino acid behave like an anion
In base
When is an amino acid neutral
Zwitterion
Which nitrogenous bases are purine?
Adenine
Guanine
Which nitrogenous bases are pyrimidine?
Uracil, cytosine, thymine
What does RNA polymerase do?
Synthesis of RNA by using dna as template. Uses one strand DNA to direct synthesis of RNA molecule.
What bond pairs nucleotides?
Hydrogen
