Biochem Midterm !

Front 1

In the solid phase, water forms ___ hydrogen bonds

Back 1

4

Front 2

What is the hydrophobic effect?

Back 2

Increased disorder of water when nonpolar molecules disclude it

Front 3

Reactions occur spontaneously when deltaG is

Back 3

Negative

Front 4

What are the 4 categories of functional groups

Back 4

Oily/hydrophobic, containing oxygen, containing nitrogen, containing sulfur and containing phosphorus

Front 5

Amphipathic/amphiphillic

Back 5

Having one or more water soluble, polar groups attached to one or more insoluble, nonpolar groups

Front 6

Carbohydrates are made from ______, nucleic acids from _______, lipids from _______ and proteins from ______

Back 6

polysaccarides, nucleotides, glycerol + fatty acids, amino acids`

Front 7

Micelle

Back 7

Molecule in equilibrium with the solution, caused my an amphipathic molecule

Front 8

Isoelectric point

Back 8

the pH where net charge of
a molecule equals zero

Front 9

At what pH is bicarbonate a good buffer? Where is it a poor buffer?

Back 9

6.4, 7.4

Front 10

Disulfide bond

Back 10

a single covalent bond between the sulfur atoms to two amino acids called cysteine to make cystine

Front 11

A left-shift of an oxygen dissociation curve means the hemoglobin is _____ saturated, this is caused by a ______ pH, ____ temp, ____ pCO2 in the :

Back 11

more, high, low, low, lungs

Front 12

A right-shift of an oxygen dissociation curve means the hemoglobin is ________, this is caused by a _____ pH, ____ temp, ____ pCO2 in the:

Back 12

less saturated, low, high, high, muscles

Front 13

What is the mechanism of phosphorylation?

Back 13

Transfer of phosphate from atp to hydroxyl amnio acids

Front 14

What is the mechanism of glycosylation?

Back 14

Attachment of complex carbohydrates to Asn or Ser

Front 15

What is the mechanism of proteolysis?

Back 15

Enzymatic cleavage of polypep chain at specific sites (rid of waste)

Front 16

Ubiquitin and proteosomes are used for

Back 16

cell cleaning/death

Front 17

Oxidoreductases

Back 17

transfer electrons in oxidation and reduction

Front 18

Transferases

Back 18

catalyze transfer of C, P, N and groups of these

Front 19

Hydrolases

Back 19

catalyze cleavage of bonds by adding water

Front 20

Lysases

Back 20

bring molecules together

Front 21

Isomerases

Back 21

makes isomers

Front 22

Ligases

Back 22

forms bonds between C and O/S/N with a lot of energy

Front 23

In lineweaver-burk plot, Y intercept is

Back 23

1/vmax

Front 24

In lineweaver-burk plot, x intercept is

Back 24

-1/Km

Front 25

Vmas is unchanged and Km is increased in which inhibition?

Back 25

Competitive

Front 26

Km is decreased and Vmax is unchanged in which inhibition?

Back 26

Non competitive

Front 27

Uncompetitive inihibition occurs when Km and Vmax are

Back 27

decreased

Front 28

COX enzymes target

Back 28

NSAIDs

Front 29

Microtubules polymerize at ___ end and depolymerize at ____

Back 29

plus, plus

Front 30

Actin polymerizes at ______ and depolymerizes at _____

Back 30

plus end, minus end

Front 31

Which end of microtubule is attached to chromosome?

Back 31

Minus

Front 32

ELISA measures antibodies quanitity by

Back 32

Colour in wells of assay plate once serum/antibodies added

Front 33

Immunoblotting is done by ____________, in which the negatively charged proteins enter the membrane by migrating towards the ______

Back 33

gel electrophoresis, anode

Front 34

Purines are:
these are ______ than pyrimidines

Back 34

Adenine, Guanine
bigger

Front 35

Pyrimidines are _____ than purines, in dna they are :

Back 35

smaller, cytosine and thymidine

Front 36

Vertical bonds in DNA are ________
(nucleotide bonds)

Back 36

non covalent H Bonds

Front 37

Transposons

Back 37

Lines and Sines, about half of the genome that is just repeated sequences of dna

Front 38

Protein coding regions only make up about ___/___ of a genome

Back 38

1/10

Front 39

Transcription

Back 39

DNA to RNA

Front 40

Exons code for ______, Introns are______

Back 40

proteins, normally spliced out

Front 41

How does DNA polymerase work?

Back 41

By adding a 5' triphosphate group to 3' hydroxyl on the template strand, moves 5'-3'

Front 42

Polymerase III can , so polymerase I

Back 42

find where bases are put in incorrectly, take it out and replace it

Front 43

What are the 3 types of pt mutations?

Back 43

Silent, Missense, Nonsense

Front 44

Silent mutation

Back 44

Amino acid is not changed by base sequence (ex. if A turns to U)

Front 45

Missense mutation

Back 45

A base is changed to another base that codes for a differentAA (if A turns to C)

Front 46

Nonsense mutation

Back 46

Codes for stop codon UGA, UAG, UAA

Front 47

Frameshift mutation

Back 47

Addition/deletion of a nucleotide that changes the reading frame

Front 48

When a lot of CAGs are found in a gene, what disease is this?

Back 48

Huntingtons

Front 49

What are the ribosomal subunits of prokaryotes?

Back 49

30s and 50s

Front 50

What are the ribosomal subunits of eukaryotes?

Back 50

60s and 40s

Front 51

How do drugs stop translation in bacteria but not in the organism?

Back 51

By binding to the small and large ribosomal subunits

Front 52

How do RNA polymerasse and DNA polymerase differ?

Back 52

RNAP does not need a primer and has no proofreading ability, the 3 types of RNAP all are used in transcription of rRNA (RNAP1), mRNA (RNAP2) and tRNA (RNAP3)

Front 53

Prokaryotic RNA has no _____

Back 53

introns

Front 54

What is the promotor regions in prokaryotes?
(transcription_

Back 54

TTGAGA and Pribnow box: TATAAT

Front 55

What is the promotor region in eukaryotes?
(transcription)

Back 55

CAAT box then Hogness (TATA) box

Front 56

Which polymerase synthesizes mRNA

Back 56

RNAP II

Front 57

What are trans acting factors?

Back 57

Proteins that bind to cis acting sequences to control gene expression

Front 58

How do transcription factors activate regulated transcription

Back 58

Signal protein begins signal cascade which phosphoylates proteins, these proteins are now activated. The final protein then enters nucleus to phosphorylate the transcription factor which then binds to enhancer on DNA to form transcription complex

Front 59

from 3' to 5', what does a mRNA strand look like

Back 59

3'- poly A tail- stop codon- lots of codons- AUG codon- cap- 5'

Front 60

Which type of chromatin is actively transcribed (ON)

Back 60

Euchromatin

Front 61

Which type of chromatin is OFF and condensed

Back 61

Heterochromatin

Front 62

What is the epigenome?

Back 62

DNA wrapped around histones

Front 63

If a protein has an N-terminus but also transmembrane domains, where is it headed?

Back 63

Mitochondria if amphipathic, ER if hydrophobic

Front 64

If a protein has a C-Terminus, where is it to be imported? retained?

Back 64

Peroxisomes, ER

Front 65

What are the 5 themes of signal transduction?

Back 65

- Ligands bind to receptors

- Formation of 2ndary messengers
- Amplification by phosphorylation

- GTP hydrolysis to activate G proteins

- Assembly of complexes by modular protein domains

Front 66

Insulin receptor is an example of what kind of membrane receptor

Back 66

enzyme coupled receptor

Front 67

When a cell is bound to GTP it is ______, but when bound to hydrolyzed GDP it is _______

Back 67

ON, OFF

Front 68

Ras protein is an example of a ___________, containing only the _____

Back 68

Monomeric G protein, alpha subunit

Front 69

Adenyly cyclase is activated by ___ to produce

Back 69

alpha subunit, cAMP

Front 70

Protein kinase A is regulated by ____

Back 70

cAMP

Front 71

HOW DOES THE mapk END

Back 71

RAS gtp gets inactivated by GAP to hydrolyze gtp to gdp

Front 72

Tumor Suppressor Gene effects the cell cycle by

Back 72

Lacking Go at G1 checkpoint, so cells can divide with problems

Rb protein doesnt bind to E2F= uncontrolled division

Front 73

Oncogenes are permanently ____, while tumor suppressor genes are permanently ____

Back 73

On, Off

Front 74

Oglionucleotides

Back 74

DNA strands that complement target DNA and therefore bind to it

Front 75

How does the PCR work

Back 75

DNA is denatured by heat then cooled so primers attach to each strand, they elongate from 5'-3' using a heat resistant enzyme

product is 4 new strands (2 dnas)

Front 76

Southern blotting, microarrays

Back 76

Genome

Front 77

To analyze the transcriptome (mRNA) we can use

Back 77

microarrays, northern blots, PCR