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Flashcards in Midterm (Exam 1) Deck (45):
1

responsible for strong negative charge of nucleic acid

phosphate group

2

semiconservative replication of DNA

parental double helix divides into two double helix DNA with one parental strand in each of the two double helices

3

eukaryotic DNA

long and multiple origins of replication

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single stranded DNA binding proteins

helix destabilizing proteins: keep the two DNA strands separate and protects against Nucleases that cleave single stranded DNA

5

DNA polymerase lll has a

5' --> 3' polymerase activity

6

3' --> 5' exonuclease

excise mismatched nucleotides during proofreading of newly synthesized DNA

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DNA polymerase l activity uses

- 5' --> 3' exonuclease activty for RNA primers
- new DNA in 5' --> 3' polymerase direction
- proovereads new chain in 3' --> 5' exonuclease

8

pol alpha

multisubunit enzyme for eukaryotic DNA replication to initiate strand synthesis on the leading strand and beginning of okazaki fragments of lagging strand

9

unlike DNA polyermase, RNA polyermase doesn't require a

primer and has no endo/exonuclease activity --> no mistmatch repair

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RNA polymerase produces

small RNA's: tRNA and rRNA

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degeneracy

redundant genetic code where some amino acids have more than one triplet coding for it

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Huntington disease

autosomal dominant

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galactosemia

autosomal recessive disorder

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locus heterogeneity

same disease phenotype by mutations at different loci

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genomic imprinting

differential activation of genes, depending on parent

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genomic imprinting example

- mutation on long arm of chromo 15 from father --> prader willi syndrome
- mutation on long arm of chromo 15 from from mother --> angelman syndrome

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- GAA triplet
- intron

Friedreich ataxia

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site of expansion and affected sequence caused by nucleotide repeat mutation; autosomal recessive

Friedreich Ataxia

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1 in 800 live births

trisomy 21

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most common chromsomal abnormality among still-borns which produces Edward syndrome

Trisomy 18

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associated with Klinefelter syndrome

Trisomy XXy (Kayrotype 47)

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Isochromosomes

chromosomes divide perpendicular to normal axis of division

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Isochromosomes results in a chromosome that

has 2 copies of one arm and no copies of the other

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Isochromosomes makes genetic material that is

substantially altered so most are lethal

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most Isochromosomes observed in live births involve

the X, so features of Turner syndrome

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MC inherited cause of mental retardation

Fragile X syndrome
- X exhibits breaks/gaps new long arm tip

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permutations tend to become larger in successive generations

Sherman paradox

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mitochondrian inheritance disease that causes progressive degen of pigment layer of retina, cardiac conduction abnormalities, ataxia, deafness, and dementia.

Kearns-Sayer syndrome

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Familial hypercholesterolemia

autosomal dominant

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hemophilia A

X-linked recessive

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Glucose-6-phosphatase defect

Ian on Gierke Disorder in the liver

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most prevalent amino acid metabolism disorder

PKU

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Maple Syrup Urine disease results from deficiency in

branched-chain a-ketoacid dehydrogenase

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what doesn't occur in the nucleus

translation

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7-sterol reductase deficiency (Smith-Lemi-Opitz) is in cholesterol biosynthesis results in

decrease levels of cholesterol and increased 7-dehydrocholesterol

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increase levels of cholesterol and increased 7-dehydrocholesterol leads to

congenital anomalies of the brain, heart, genitalia and hands

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urea cycle disorders include

hyperammonemia and ornithine transcarbamoylase

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hyperammonemia causes

mental retardation, coma, and death

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ornithine transcarbamoylase is the only

X-linked enzyme, others are autosomal recessive

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Lyon hypothesis

one X chromosome in each cell is randomly inactivated early in the embryonic development of females

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dosage compensation

females with two copies of the X chromo will produce X-linked gene products similar to males

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X-linked dominant inheritance patterns

50% sons affected and 50% daughters affected

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d-linked recessive inheritance patterns

50 % of sons affected and 50% of daughters heterozyous carriers

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trisomy 13 produces

Patau syndrome

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karyotype 45, X produces

Turner syndrome (female)