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Flashcards in Exam 4 Deck (90)
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1

Triacylglycerols are stored in _______ cells in animals

Adipose

2

The hormones _________ stimulate lipolysis when energy reserves are low.

Epinephrine and Glucagon

3

The brain uses __________ instead of glucose for its source of ATP production during long-term fasting

Ketone bodies

4

In diabetes, untreated chronic ketone body production will ______ blood pH levels.

Lower

5

Beta oxidation of odd-numbered fatty acids produces acetyl CoA and ______

Propionyl CoA

6

Fatty acids synthesis primarily takes place in the _______

cytoplasm

7

________ is the product of the committed step in fatty acid synthesis

Malonyl CoA

8

Citrate serves as signal for a high-energy state as it stimulates _______

Acetyl CoA Carboxylase

9

Double bonds are introduced into fatty acids in the ________ compartment of the cell

Endoplasmic Reticulum

10

Glycerol released during lipolysis is absorbed by the liver for use in:

Glycolysis and Gluconeogenesis

11

Fats stored in adipose tissue is used by the liver and other tissues for:

Making ketone bodies and conversion of acetyl CoA for the CAC

12

Fatty acids are linked to glycerol with:

Ester linkages

13

Complete oxidation of palmitate yields _____ molecules of ATP

106

14

Enzymes that digest the triacylglycerols into free fatty acids and monoacylglycerol are called:

Lipases

15

Acetyl CoA carboxylase is globally regulated by:

Phosphorylation and desphosphorylation

16

Intermediates from which pathways are utilized for fatty acid synthesis

-Glycolysis
-CAC
-PPP

17

Activation of acetyl CoA results in the production of

Malonyl CoA

18

Which of the following is essential fatty acid?

Linoleate

19

The carrier of an acyl chain through the synthetic protein complex is

ACP

20

Excess NH4+ is converted into urea by the_____

urea cycle

21

The hydrolysis of arginine by arginase produces ornithine and ______

Urea

22

The urea cycle id linked to gluconeogenesis via formation of _____, a precursor of glucose synthesis

Furmate

23

Succinyl CoA is a point of entry into the citric acid cycle of _______

Nonpolar Amino Acids

24

_________ transfer amino groups from an amino acid to alpha-ketogluatarate

Aminotransferases

25

An amino acid that serves as a nitrogen source in the synthesis of amino acids from alpha-ketoacids is ______

glutamate

26

The process of converting N2 to NH3 is called_____

Nitrogen Fixation

27

The final product pathway, which inhibits an enzyme that catalyzes its production typically, takes place at the ________ step.

Committed

28

Glutamine synthetase is an example of _______ inhibition

Cumulative Feedback

29

______ is a versatile nitrogen donor in the synthesis of a wide range of compounds

Glutamine

30

In the Urea cycle, the second nitrogen of urea enters the cycle in the form of which metabolite?

Aspartate

31

The urea cycle is

a way to remove excess NH4+

32

Which amino acids can be directly deaminated to produce NH4+

Serine and Threonine

33

In the urea cycle, free NH4+ is coupled with carboxyphosphate to form

Carbonic acid

34

Ketogenic amino acids are degraded to which metabolites?

Acetyl CoA and Acetoacetyl CoA

35

Organisms capable of carrying out reduction of atomspheric nitrogen include

Some bacteria

36

The carbon skeletons for amino acids are intermediates found in

Glycolysis, CAC, and PPP

37

Amino acids synthesized by humans are

nonessential amino acids

38

Transaminases use what as a coenzyme

Pyridoxine

39

3-Phosphoglycerate is the precursor for

Serine, Glycine, Cysteine

40

In bacteria, the _________ sequence is a purine rich region that is approximately 10 base pairs upstreams of the start site and directs the protein synthesis machinery to the start site

Shine-Dalgarno

41

________ si the initial amino acid in a bacterial protein

fMet

42

_______ include IF1, IF2, and IF3 in prokaryotes and are required for the invitation of protein synthesis

Initiation factors

43

G or translocase use the energy of _____ hydrolysis to move the mRNA by one codon in protein synthesis

GTP

44

In the ribosome, A stands for _______ and P stands for_______

Aminoacyl and Peptidyl

45

Proteins are synthesized from the ________ direction

amino-carboxyl

46

Sixty percent of human genes are regulated by____

mirco RNA

47

Eukaryotic mRNA is

circular

48

Chloramphenicol acts by:

inhibiting peptidyl transferase activity on the 50S ribosome

49

Peptide bond formation is

Exergonic and catalyzed by 23S RNA

50

What is the direction of translation of mRNA

5'-3'

51

Signals that define the beginning and end of protein synthesis are contained in:

mRNA

52

What factors are necessary for the correct placement of mRNA ash initiating tRNA on the ribosome?

IF1, IF2, IF3

53

Eukaryotic and prokaryotic translation differs primarily in which step?

initiation

54

What is the order of tRNA binding sites on the 70S ribosome with respect to the 5'-3' direction of the mRNA

EPA

55

Elongation factor G is also called what?

translocase

56

A group of genes under the control of a single promoter

Operon

57

________ is a required cofactor for RNA polymerase

Covalent Cation

58

DNA sequences that direct RNA polymerase to the initiation site are called________

Promoters

59

Expression of B-galactosidase requires the induction of an operon by removal of a______

repressor

60

Promoter sites in E.Coli are located _____ and ______ nucleotides upstream of the start site

-10 and -35

61

The first step of transcription in eukaryotes depends on the ______ subunit of RNA polymerase

Sigma

62

Cis-acting elements that have no promoter activity but can stimulate the effectiveness of promoters are called _______

enhancers

63

The enzyme that removes the acetyl group for a lysine of a histone is called_______

histone deacetylase

64

In eukaryotes, transcription is initiated by the binding of a transcription factor to the _____ box, which is located -24 and -32 upstream of the initiation site

TATA

65

The nuclear membrane is important in gene expression because it separates the processes of ______ from that of ______

Transcription and Translation

66

In prokaryotes function of RNA Polymerase are

-Searching for promoter sites
-unwinding short stretches of DNA
-detecting termination signals

67

The pribnow box is:

the site where promoters bind

68

The protein that binds DNA sequences and helps RNA polymerase initiate transcription is

sigma

69

In transcription, the 3' hydroxyl group

attacks the alpha-phosphoryl group on an incoming nucleotide

70

In E.coli what proteins are synthesized when B-galactosidase is synthesized?

-sigma 70 of RNA Polymerase
-RNA helicase
-Fibonuclease
-galactoside permease

71

In eukaryotes RNA polymerase II

-is sensitive to alpha-amanitin
-catalyzes mRNA synthesis

72

In eukaryotes enhancer sites are often located

at a distance from the transcription start site

73

Differential gene expression is caused by

control of transcription

74

Cis-acting elements

are DNA sequences the regulate expression

75

Noncoding regions of RNA are called

intron RNA

76

RNA polymerase I is responsible for the transcription of

18S rRNA and 28S rRNA

77

What modifications are made to eukaryotic tRNA transcripts

-Modification of base and ribose moieties
-An intron removed by endonuclease
-Cleavage of the 5' leader by RNase P
-The nucleotides CCA are added

78

The 5'cap of mRNA

-contains GTP in a 5'-5' linkage
-protects mRNA

79

The polypyrimidine tract

-is found at the 5' end of a junction
-is found at the 3' end of an intron
-contains a stretch of 10 pyrimidines

80

A spliceosome is made of

snRNP and snRNA

81

Thallasemia can occur when there are mutation in pre-RNA or splicing factors of:

hemoglobin beta

82

Ribozymes are

RNA

83

The carboy-terminal domain of RNA polymerase II

Binds factors need for pre-mRNA capping, splicing, and polyadenylation

84

A mutation in an enzyme that catalyzes a transesterification reaction would inhibit

mRNA splicing

85

Nearly all mRNA precursors in higher eukaryotes are modified by

Splicing

86

_________ catalyzes the synthesis of precursors for tRNA

RNA polymerase III

87

Recognition of the 5' splicing site by ____ is the first step in splicing

U1

88

Self-splicing by RNA requires a ______ cofactor

guanosine

89

The immediate product go RNA polymerase II is referred to as _____

pre-RNA

90

The ______ is the elongated sequence added to the 3' end of mRNA

Poly A tail