241 - 32, Cytoplasmic inheritance Flashcards Preview

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Flashcards in 241 - 32, Cytoplasmic inheritance Deck (64)
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1
Q

cytoplasmic organelles behave differently and DO / DO NOT not obey Mendelian rules.

A

do not

2
Q

Mitochondria are organelles that use ______ to produce energy efficiently

A

oxygen

3
Q

Mitochondria have their own _____

A

genomes (DNA)

4
Q

The human mitochondrial genome encodes __ genes: __ ribosomal RNA genes, __, tRNA genes (for protein synthesis), and __ proteins for energy metabolism

A

37, 2, 22, 13

5
Q

The majority of mitochondrial proteins are made from ______ genes.

A

nuclear

6
Q

_________ theory - Mitochondria (and chloroplasts) were derived from a symbiosis of an anaerobic eukaryotic cell and an aerobic prokaryotic cell. Many features of mitochondria resemble those of bacteria.

A

endosymbiant

7
Q

Mutations disrupting the energy production process will affect the growth on non- fermentable ______

A

sugars

8
Q

________ petite: The transmission of the phenotype follows the Mendelian pattern. These mutations affect nuclear genes that contribute to energy production in mitochondria.

A

segregational

9
Q

______ petite: The mutant mitochondria are “recessive” to the wild-type ones.

A

neutral

10
Q

In neutral petite, the four meioses inherit some . . . (type) mitochondria to restore their ability to grow on non-fermentable sugars.

A

wild-type

11
Q

________ petite: the mutant mitochondria are “dominant” to the wild-type ones.

A

suppressive

12
Q

the inheritance of mitochondria is from . . .

A

the mother

13
Q

Mitochondrial diseases usually exhibit the following features (3)

A

maternal transmission
variable penetrance
expressivity

14
Q

_________ component: stored in eggs as mRNA, proteins, and organization

A

maternal

15
Q

________ component: newly transcribed materials from the embryonic genome

A

zygotic

16
Q

The effects of mutations in maternal-effect genes are manifested in the ______

A

progeny (not the mothers)

17
Q

_____ are the disease-causing agents for spongiform encephalopathy, mad cow disease.

A

prions

18
Q

_____ alter cellular phenotypes through self-perpetuating changes in protein conformation and are cytoplasmically partitioned from mother cells to daughter.

A

prions

19
Q

prions are partitioned from _____ to _____

A

mother to daughter

20
Q

prions are susceptible to _______

A

proteases

21
Q

______ are resistant to UV and nuclease treatment

A

prions

22
Q

In yeast, _______ petites mutants that show Mendelian behaviour and result from mutations in mitochondrial genes located in the nucleus.

A

segregational

23
Q

In yeast, ______ petites, which are recessive genotypes and result from the complete absence of mitochondrial DNA.

A

neutral

24
Q

In yeast, ________ petites, in which most of the mitchondrial DNA is lost (60-99%), though what remains is often amplified.

A

suppressive

25
Q

________ ensure the proper segregation of genes during mitosis and meiosis

A

centromeres

26
Q

Molecules that are not linked to chromosomes bearing nuclear centromeres behave differently during _______ and do not obey ______ rules

A

mitosis; Mendel’s

27
Q

_________ are involved in producing energy for the cell through oxidative phosphorylation

A

Mitochondria

28
Q

nuclear DNA is ______ and mitochondrial _______ (shape)

A

linear; circular

29
Q

nuclear DNA cells contain ___ copies of DNA, mitochondria cells contain _____ copies of DNA

A

2; 1000s

30
Q

endosymbiont theory suggesting mitochondria are bacteria was proposed by _____ _______

A

Lynn Margulis

31
Q

there are >_____(#) genes in nuclear DNA, ___ genes in mitochondrial

A

> 30,000; 37

32
Q

there are similar _____ compositions in membranes of bacteria and mitochondria (endosymbiont theory)

A

lipid

33
Q

bacterial and mitochondrial genomes are ______ (shape) (endosymbiant theory

A

circular

34
Q

bacteria and mitochondria have similar ____ (endosymbiant theory)

A

rRNA

35
Q

In yeast, mitochondria are contributed by . . ., in humans . . .

A

yeast - both parents

humans - mother

36
Q

Mutations in essential
mitochondrial genes, or nuclear genes that affect mitochondrial function, results in a
slow-growth phenotype on non-fermentable sugars (called _____)

A

petite

37
Q

the high mutation rate of mitochondria suggests that the _____ mechanism IS / IS NOT as efficient as nuclear DNA

A

repair mechanism IS NOT

38
Q

the high mutation rate of mitochondria suggests that there are many mutagenic ____ ________ around mitochondria

A

free radicals

39
Q

yeast petite colonies are _____ than normal colonies

A

smaller

40
Q

in segregational mutation in yeast petites the offspring will be . . .

A

1/2 petite, 1/2 normal

41
Q

in neutral mutation in yeast petites the offspring will be . . .

A

all normal

42
Q

in suppressive mutation in yeast petites the offspring will be . . .

A

all petite

43
Q

myoclonic epilepsy and ragged red fiber disease is abbreviated . . .

A

MERRF

44
Q

ataxia, deafness, dementia, and epileptic seizures are all due to . . .

A

MERRF (myoclonic epilepsy and ragged red fiber disease)

45
Q

muscle fibers exhibit blotchy red patches resulting from the proliferation of aberrant (non-normal) _________ in what condition . . .

A

mitochondria; MERRF

46
Q

in general, all the mitochondria in an individual are genetically _______

A

identical

47
Q

________ - the existence of a uniform population of organelles within a cell or an individual

A

homoplasmy

48
Q

________ - the existence of a variety of organelles within a cell or individual

A

heteroplasmy

49
Q

proportion of mutant mitochondria determines the severity of the _____ phenotype

A

MERFF

50
Q

HIGH / LOW energy requirement = least tolerant of mutant mitochondria

A

high

51
Q

Tissues with LOW / HIGH energy requirements (e.g., skin) are only affected when the proportion of wild- type mitochondria is greatly reduced.

A

low

52
Q

_______ component: stored in egg as mRNA, protein and organization

A

maternal

53
Q

_________ (______) component: newly transcribed from the embryonic genome

A

embryonic (zygotic)

54
Q

the _______ of the mother determines the inheritance of maternal effect genes

A

genotype

55
Q

_____ diseases are called spongiform encephalopathies because of post mortem appearance of the brain large vacuoles in the cortex and cerebellum

A

prion

56
Q

scrapie, TME, CWD, BSE (mad cow), CJ, GSS, FFI, Kuru all examples of _____ diseases

A

prion

57
Q

______ resist inactivation by procedures that modify nucleic acids.

A

prions

58
Q

UV treatment’s effect on prions (scrapie)

A

none

59
Q

the infectious prion PrP^Sc similarities to PrP^C are . . .

A

exact same

60
Q

knockout mice lacking PrP are resistant to ______

A

prions

61
Q

In Saccharomyces cerevisiae, a cross between a haploid suppressive petite mutant and a haploid wild type results in petite diploid progeny. This is because of . . .

A

deletions in the mtDNA

62
Q

nonfunctional mutant mitochondria proliferation advantage in ________ petite because there are deletions in the mtDNA

A

suppressive

63
Q

The transmission of prion is sensitive to the treatment of

A

protease

64
Q

The maternal-effect mutation torso (tor) is recessive. In the absence of the torso protein product, embryogenesis is not completed (missing both head and tail structures). Consider a cross between a female heterozygous for the torso (tor+/tor-) and a male homozygous
for the mutation (tor-/tor-).

A

all are normal