Thread of Life Flashcards
3 Ethical issues with DNA fingerprinting and testing:
- Who owns and has access to genetic information?
- Should parents have the right to test their children?
- Should tests be performed for genetic diseases?
What four steps are uses to form a DNA fingerprint?
1- DNA sample cut into fragments using a restriction enzyme
2- Fragments separated by electrophoresis
3- Fragments marked with a probe and exposed on x ray film
4- black bars are produced which is the fingerprint
What is the order of a substance with a constant half life?
1st order
What effect does increasing temperature have on k?
The value of k increases
What step are particles in the rate equation involved in?
The rate determining step
What is the rate determining step?
The slowest step in a multi step reaction
In a first order reaction what happens to rate when conc of the reactant is doubled?
It doubles
What are optical isomers?
Molecules with a chiral centre that are non- superimposable mirror images
What is a racemic mixture?
A mixture with a 50:50 mixture of d and l isomers
What two functional groups do amino acids contain?
Carboxyl COOH and Amino NH2
What does an amino acid form in a neutral solution?
A zwitterion
What happens to an amino acid in an acidic solution?
The amino group is protonated
What type of reaction joins forms a polypeptide and what are the bonds between amino acids?
Condensation
peptide
What are the four bonds that maintain a protein’s tertiary structure?
ID-ID
hydrogen bonds
Ionic bonds
Covalent bonds
What are the conditions and reagents for hydrolysis of proteins?
Mod conc acid/alkali
Reflux
How can amino acids be identified?
TLC with ninhydrin locating agent
At low concentrations of substrate, what is the order with respect to the substrate and what is the rate equation?
Rate= k[E] [S]
First order
At high concentrations of substrate what is the rate equation and order with respect to the substrate?
Rate = k[E]
Zero order
Why are enzymes used in industry?
Specific
Work at low temps
Work in aqueous environment
Higher atom economy
How are reactive metals extracted?
By electrolysis
How are less reactive metals extracted?
By reduction with carbon/CO
Examples of barrier protection?
What does it prevent?
Paint, grease, oil, polymer coating
Oxygen/water coming into contact with iron and steel
What is sacrificial protection?
attaching a more reactive metal to iron structures, the reactive metal oxidises instead of the protected metal
What is a transition metal?
A d block element which forms at least 1 ion with a partially filled d sub shell
