Exam 3

Question 1

the experiements with nutritional mutants in Neurospora by Beadle and Tatum provided evidence that:

Answer 1

genes specify enzymes

Question 2

the “central dogma theory” holds true for all protein synthesis.(T/F)

Answer 2

false

Question 3

in the genetic code, one codon..

Answer 3

consists of 3 bases and spedifies a single amino acid

Question 4

in your textbook, there is a picture of a piglet with a flurorescing nose and ears ust like that found in a jellyfish. this demonstrates:

Answer 4

the genetic code is universal (except for a few minor exceptions)

Question 5

a given codon can call for atleast 3 different amino acids. (T/F)

Answer 5

false

Question 6

which respec to RNA polymerase and the formation of RNA, there is no proofing (T/F) because:

Answer 6

True; RNA is short-lived, therefore errors do not accumulate or exist for any length of time

Question 7

“caps” and “tails” occur in _____ and are important to _____.

Answer 7

eukaryotes; prevent exonuclease activity

Question 8

the human genome contains ~25000 genes but can encode for > 80000 different mRNA. this is explained by

Answer 8

alternative gene splicing

Question 9

which of the following is ‘bifunctional” molecule?

Answer 9

tRNA

Question 10

consider rRNA and polypeptide sequencing. the enzyme ____ couples the _____ from the amino acid in site A to the ____ on the amino acid in site P.

Answer 10

,

Question 11

Ee-Tu is responsible for __ and is the only known example of “validation” in an RNA system.(T/F)

Answer 11

bringing tRNA to mRNA and making sure the codons are correctly paired; True

Question 12

what is a gene?

Answer 12

a stretch of DNA that codes for a type of protein or for an RNA chain that has a function in the organism

Question 13

if the anti codon on the tRNA is UACGAU, what is the nucleotide sequence in DNA?

Answer 13

TACGAT

Question 14

RER is so named becasue of the association of the membrane with ___. these organelles are physically attached (T/F) to the RER by ___.

Answer 14

rRNA; false; the synthesizing polypeptide chain.

Question 15

the key finding from Griffith’s experiment was:

Answer 15

genetic material can be transferred from dead to live bacteria.

Question 16

the person who actually discovered DNA and named it “nuclein” was:

Answer 16

friedrich miescher

Question 17

chargaff studied the composisiton of DNA from different sources and found that:

Answer 17

A = T, G = C

Question 18

___bonds hold nucleotides together, but complemetary strands of DNA are held together by____.

Answer 18

phosphodiester; hydrogen

Question 19

in the hershey-chase experiement,

Answer 19

DNA from parent bacteriophage appeared in progeny bacteriophage

Question 20

watson and crick based their interpretation of the structre of the DNA molecule on the lab research from their own lab which had recieved extensive funding from the british royal academy of science. (T/F)

Answer 20

false

Question 21

New DNA is synthesized:

Answer 21

in the 5’ to 3’ direction

Question 22

primase

Answer 22

tells DNA polymerse where to begin copying

Question 23

DNA polymerase I

Answer 23

removes primers and fills gaps

Question 24

DNA polymerase III

Answer 24

the major enzyme that synthesizes DNA

Question 25

Replisome

Answer 25

composed of a primose and 2 DNA Pol III enzymes

Question 26

Ligase

Answer 26

joins the DNA segments

Question 27

one strand of DNA has the sequence 5'-ATTCCG-3'. The complemetary strand for this is:

Answer 27

3'-TAAGGC-5'

Question 28

okazaki fragments are found:

Answer 28

in the lagging strand

Question 29

the difference between "leading" and "lagging" strand synthesis is:

Answer 29

both the physical structure of DNA and the action of polymerase enzyme on the lagging strand.

Question 30

telomeres

Answer 30

protect the ends of DNA strands

Question 31

replication of eukaryote DNA begins at one end of the DNA molecule and proceeds in linear. (T/F)

Answer 31

false

Question 32

prokaryotes reproduce asexually by ____ and do not require ____.

Answer 32

binary fission; assembly or disassembly of a nuclear membrane

Question 33

a nucleosome is...

Answer 33

a complex of DNA plus histone protiens composed of arginine and lysine

Question 34

the FtsZ protien in prokaryotes shows a high degree of similarity to _____ in eukaryotes.

Answer 34

tubulin

Question 35

chromatids are held together by ______and become independent chromosomes in ____.

Answer 35

cohesion; anaphase

Question 36

in congression, it is important that homologous chromosomes eventually pair on the metaphase plate. (T/F)

Answer 36

false

Question 37

epidermal growth factor is found in _____ and would be responsible for _____.

Answer 37

saliva; atimulating certian cells to divide by overriding mitotic control mechanisms.

Question 38

the protien, p53, plays a key role at the ____checkpoint. its role is to monitor ____. if there are problems, p53 can cause ___. if p53 is damaged, ____ usually results.

Answer 38

G1/S; DNA integrity; apoptosis; uncontrolled cell division

Question 39

in the process of mitosis, one of the last structure to leave and one of the fist structures to form is/are _____ becasue it/they is/are the site of _____which produce ____.

Answer 39

the nucleolus; rRNA synthesis; protiens (enzymes)

Question 40

green plants are autotrophs and produce their own food resources. heterotrophs feed on plant material. therefore, heterotrophs are the only gropu to use cellular respiration and oxidative phosphorylation. (T/F)

Answer 40

false

Question 41

the role of oxygen gas in our cells is to:

Answer 41

accept electrons from the electron transport chain and produce H20

Question 42

the process of splitting larger molecules into smaller ones is an aspect of metabolism called:

Answer 42

catabolism

Question 43

if an enzyme is used to produce ATP directly, this is called ____.

Answer 43

substrate phosphorylation

Question 44

the synthetic aspect of metabolism is called_____.

Answer 44

anabolism

Question 45

the reactions of _____ take place in the cytoplasm of eukaryotic cells.

Answer 45

glycolysis

Question 46

without the resynthesis of ____, glycolysis would stop.

Answer 46

NAD+

Question 47

we disscussed "energy of activation" in chapter 6. energy of activation is required to begin the metabolism of glucose. therefore, ___ molecule(s) of ___ are required to initiate the catabolism of each molecule of glucose.

Answer 47

2; ATP

Question 48

what is the "net" energy producton of one molecule of glucose in glycolysis?

Answer 48

2 molecules of ATP; 2 molecules of NADH

Question 49

what happens in glycolysis in animal cells if ther eis an insufficient amount of oxygen being supplied to the cells where glycolysis is occuring?

Answer 49

pyruvate is converted to Lactate

Question 50

which of the following BEST explains the coupling of glycolysis and the Krebs Cycle?

Answer 50

the oxidation of pyruvate, the generation of NADH from NAD+, the loss of a CO2 molecule and the formation of acetyl-co A

Question 51

in the krebs cycle, the 4-c molecule ___picks up acetyl-co A and forms the 6-C molecule ____ which also gives the krebs cycle is second name, the ___cycle.

Answer 51

oxalocetic acid; citric acid; citric acid

Question 52

in the kreb cycle specifically, for each molecule of pyruvate that enters the cycle through acetyl co A, ___ molecules of CO2 are produced by ___, and in the process, the high energy molecule ___ is formed for each molecule of CO2 produced.

Answer 52

2; decarboxylation; NADH

Question 53

methanogens use ____ as a final electron acceptor to produce ____.

Answer 53

CO2; CH4

Question 54

in respiration, which is reformed first- water or carbon dioxide and where is this molecule produced?

Answer 54

carbon dioxide - in the krebs cycle

Question 55

chemiosmosis results from:

Answer 55

electrons moving through the ETC, creating a proton gradient, and H+ moving though ATP synthase to produce ATP.

Question 56

the actual yeild of ATP from a mole of glucose is different than the theoretical yeild. this difference has to do with:

Answer 56

the energy required to move NADH and pyruvate into the mitochondrial matrix.

Question 57

thermogenesis occurs when the H+ _____.

Answer 57

pass through a channel in the mitochondrial inner membrane created by an uncoupling protien into the mitochondrial matrix and produce heat rather than ATP

Question 58

beta-oxidation is the process by which ___ are converted to ____.

Answer 58

2-carbon units of fatty acids chains; acetyl-co A

Question 59

high levels of ATP can inhibit the enzyme_____ which is the control point for ____.

Answer 59

phosphofrucktokinase; converting fructose 6-phosphate to fructose 1,6-bisphosphate