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Flashcards in exam 4 Deck (61):
1

Repressible operon

(product needed at all times) protein that inhibits operator ON gene transcription

2

Inducible operon

transcription may not be initiated at all unless its product becomes needed by the cell.
(transcription occurs only in the presence of a substrate)

3

lactose absent

repressor active, operon OFF (block RNA pol from binding to operator

4

lactose present

repressor inactive, operon ON (RNA pol binds to operator

5

Lac operon

is a negatively controlled inducible operon, where the inducer molecule is allolactose

6

Heteroplasmy

having diff genotypes of mitochondria in a cell

7

Panmixis

the Hard-W assumption about mating (random mating)

8

assortative mating

matting patern and a form of sexual selection in which ind w similar phenotypes mate w each other more frequently.

9

positive assortative mating

like mating w like, increase homozygosity for genes on which mate choice based (WILL CHANGE GENOTYPE FREQ, BUT NOT ALLELE FREQ

10

negative ass. mating

mating w unlike, increase heterozygosity for genes on which mate choice is based

11

inbreeding

increase homozygosity for entire genome (happens when pop is reduced)

12

founder effect

settling on an uninhabited island

13

posttranslational mod

mod of the protein product. ex: removing an amino acid, phosphorylation, linking 2 or more polypeps to form a functional protein as in hemoglobin

14

processing control

removing introns, which can vary from one cell/time to another for the same initial hnRNA

15

transport control

differential transport of products into and/or out of the nucleus through nuclear pores

16

snRNA

small nuclear ribonucleic protein, are RNA-protein complexes that combine w unmodified pre-mRNA and various other proteins to form a spliceosome, a large RNA-protein molecular complex upon which splicing of pre-mRNA occurs

17

hnRNA

the initial transcript produced by an active gene in eukaryotes

18

cpDNA

known as the plastome when referring to genomes of other plasmids (haploid)

19

TFIID

1st protein to bind to DNA during the formation of the pre-initiation transcription complex of RNA poly II
(binding of TFIID to the TATA box in the promoter region of the gene initiates the recruitment of other factors required for RNA pol II to begin transcription)

20

If a mutation occurs in the promoter of an operon, what happens to translation?

translation would be permanently blocked

21

blastoderm stage

its nuclei typically begin to transcribe their own genes

22

murula stage

final stage prior to formation of a fluid filled cavity called the blastocoel cavity

23

gastrulation

week 3;day 17... after fertilization which a single-layered blastula is organized into a multilayered structure known as the gastrula

24

mesoderm

forms the muscles and other organs b/n the digestive tract and ectoderm

25

endoderm

the inner layer of cells becomes the endoderm, which lines the primitive digestive and respiratory system

26

ectoderm

the outer layer, covers the surface of the embryo and differentiates into the epidermis and the nervous system

27

promoter

specific nucleotide sequence in DNA that binds RNA poly, positioning it to start transcribing RNA at the appropriate place

28

RNA polymerase

binds to promoters in bacteria and transcribes the coding regions of genes

29

operator

regulatory proteins bind here to control expression of the operon

30

stabilizing selection

(ex: birth weight)
-doesnt change average tail expression
-reduces phenotypic variance
-the current condition is beneficial for the pop

31

directional selection

-change average trait expression
-has only temp. effects on the variance in expression
-changed conditions require the pop to alter its appearance, physically, or behaviors

32

H.W assumption (no selection)

no difference in the relative genetic contribution of each genotype to the next generation

33

HW ass. (no migration)

no movement of genes into or out of the gene pool

34

HW ass. (diploid genotype)

two alleles of each gene per individual

35

HW ass. (infinite population size)

the population is so large that random sampling variation will not have an effect

36

HW ass. (no mutation)

no genetic change of one allele into the other

37

HW ass. (panmixis)

random mating (include positive or negative mate choice)

38

translational control

not all mRNAs bind to the ribosomes equally and mRNAs differ in their longevity w/in the cell

39

totipotency

the ability of a nucleus to code for normal development of a new individual w all its varied cell types

40

transfer RNA (tRNA)

which transfers spec. amino acids to growing poly chains at ribosomal site of protein synthesis
-tRNA is transcribed by RNA poly III

41

Ribosomal RNA (rRNA)

make up components of the ribosomes
-rRNA is transcribed by RNA poly I

42

Messenger RNA (mRNA)

template for the synthesis of proteins by ribosome
-mRNA/snRNA/ and microRNA transcribed by RNA poly II
-MOST OF THE mRNA THAT IS TRANSCRIBED IN EUK. NEVER ACTUALLY LEAVES THE NUCLEUS

43

microRNA

regulatory gene activity and catalytic RNA

44

CAAT box

found in regulatory promoters. Its freq absent in genes that encode proteins used in virtually all cells

45

DNA 1-6

1. Transcriptional control
2. Processing control
3. Transport control
4. Translational control
5. Post-translational modification
6. RNA stability

46

cellular differentiation

differences in the proteins and related biochemical activities in different types of cells

47

pattern formation

spatial diff in cellular differentiation how are diff cell types patterned w/in an organism

48

morphogenesis

"origin of the form"
changes in shape and form due to movement of cells and sheets of cells (ex:gastrulation and neurulation)

49

hemoglobin molecule

combination of 2 alpha and 2 non-alpha chains produce a complete hemoglobin molecule
-they are closely balanced, but disruption in the balance produces a disorder called THALASSEMIA

50

protein hormone

given the way they influence phenotypic changes in a cell or tissue, the action of a protein hormone would tend to be faster that the alternative type of hormone effect

51

SPLICEOSOME

composed of several SnRNPs
-smaller nuclear ribonucleoproteins
-the SnRNPs attach sequentially to the RNA

52

TBP

TATA binding protein- its a general transcription factor that binds to the TATA box

53

HW equations

p^2+2pq+q^2
p+q=1
p=1-q

54

An operon:
"I"

repressor- a protein (negative regulation)synthesizes a protein that represses operon transcription (produces a repressor that binds to O)

55

An operon:
"P"

promoter- binding site RNA polymerase

56

An operon:
"O"

operator- binding site for a repressor or activator

57

An operon:
Z

B-galactosidase= cleaves sugar to monosaccharides

58

An operon:
Y

permease- allows lactose to enter the cell

59

An operon:
A

Transacetylase- function unclear (dispensable) Detoxification and excretion?

60

maternal effect

affects the next generation, but not the generation after

61

morphogens

a sub. whose non-uniform distribution governs the pattern of tissue development- typically diffusing through tissue early development forming concentration gradients