Biochemistry Flashcards
Bond strengths in order. Strongest to weakest?
Covalent Ionic Hydrogen Hydrophobic interactions VDW's
Oxidation states of carbon?
Alkane (in fats) Alcohol (in carbs) Aldehyde Carboxylic acid Carbon dioxide
4 major classes of biomolecules and what they consist of?
Proteins/peptides= amino acids
Lipids= triglycerides, phospholipids, steroids
Nucleic acids= DNA/RNA
Carbs= Mono, di, poly saccharides
Example of monosaccharide?
Glucose
Examples of disaccharides?
Lactose
Examples of polysaccharides?
Cellulose
Glycogen
1st law of thermodynamics?
Energy can neither be created nor destroyed
2nd law of thermodynamics?
When energy is converted from one form to another some of that energy becomes unavailable to do work
What type of reaction is it if the change in free energy is negative?
Exergonic (can occur spontaneously)
What type of reaction is it if delta G is positive?
Endergonic (cannot occur spontaneously)
Entropy?
Loss of useable energy
Primary protein structure?
Sequence of amino acids
Secondary protein structure?
Formation of backbone
Tertiary protein structure?
3D structure
Quaternary protein structure?
Spatial arrangement of multiple subunits
What holds proteins together?
Disulphide bonds
5 elements of a cell?
SER RER Mitochondria Golgi apparatus Ribosomes
Role of SER?
Synthesis of steroid hormones
Role of RER?
Synthesizes polypeptides
Role of mitochondria?
Powerhouse of cell can multiply independently
Role of golgi apparatus?
Receives materials from ER and distributes, also modifies proteins
Role of ribosome?
Where RNA is translated into protein
Prokaryote?
Microscopic single cell organism that does not have a defined nucleus
Eukaryote?
Normal cell with normal nucleus
Structure of DNA?
Nucleoside = base + sugar Nucleotide = nucleoside + phosphate
Examples of purines?
Adenine and guanine
What is collective term for base A&G?
Purines
Collective term for C, T & U?
Pyrimidines
Examples of pyramidines?
Cytosine
Thymine
Uracil
What direction is DNA replication?
Always in 5’->3’ direction
What type of primer is required for DNA repication?
RNA primer
DNA replication is catalysed by DNA polymerases. True or false?
True
Which strand always has a free 3’ end?
Leading strand
What unwinds DNA in DNA replication?
DNA helicase
How are okazaki fragments made?
Lagging strand is replicated in short fragments
What are the short replicated fragments of the lagging strand in DNA called?
Okazaki fragments
What does RNA contain?
Stem loop
3 types of RNA?
rRNA (ribosomal)
mRNA (messanger)
tRNA (transfer)
Role of rRNA?
Combines with proteins to from ribosomes where protein synthesis takes place
Role of tRNA?
Carries amino acids to be incorporated into protein
Role of mRNA?
Carries genetic information for protein synthesis
How many nucleotides do anticodons consist of?
3
How many types of RNA polymerases do
- prokaryotic cells have
- Eukaryotic cells have?
- 1 type for pro
- 3 types for eu
Types of RNA polymerase in a eukaryote?
Pol i, ii, iii
Which RNA polymerase synthesizes all mRNA?
Pol ii
Stages of transcription?
- RNA polymerase binding
- DNA chain separation
- Transcription initiation
- Elongation
- Termination
What happens in first stage of transcription?
RNA polymerase binding
- Detects initiation sites on DNA
- Requires transcription factors
What does first stage of transcription require?
Transcription factors
2nd stage of transcription?
Unwinding of DNA