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Flashcards in Genes and Chromosomes Deck (48):
1

what is short arm of chromatid called?

p arm

2

what is the long arm of chromatid called?

q arm

3

what is chargaff's rule

purines = pyrimidines
A + G = T + C

4

what is complementary strand of
5' CGGTACT 3'

5' AGTACCG 3'

5

what can anti parallel strand of DNA be used for?

primer for PCR or ASO probe for mutation detection

6

are both introns and exons transcribed and translated?

introns and exons are both transcribed but only exons are translated

7

purpose of alternative splicing

to form different proteins from one gene

8

name some regulatory sequences and what do they do

enhancers, silencers, promoters

they regulate the rate of transcription

9

how does methylation (an epigenetic modification) affect transcription

the more methylated, the less effective transcription is

10

makeup of DNA

nuclear, extragenic DNA (repetitive), and mitochondrial

11

where is highest gene density

subtelomeric region

12

noncoding region of DNA

centromere, telomere, and heterochromatic region

13

what is nuclear coding DNA

unique single copy genes and multigene families

14

difference between single gene and multigene

single gene - codes for only one protein
multigene - genes with similar functions that have arisen by gene duplication

15

what is extragenic DNA

the other 98% of our DNA that is not transcriptionally active and appears nonfunctional

might play a role in regulation of gene expression

16

importance of STR (short tandem repeats)

fingerprinting (microsatellite)

17

polymorphic and inherited in a codominant fashion

STR (short tandem repeats)
VNTR (variable number of tandem repeats)

18

subgroups of tandem repeats

satellite, minisatellite, microsatellite

19

satellite DNA are usually clustered around?

centromeres of chromosomes

20

importance of telomeres

necessary to prevent shortening of chromosomes

21

previously used for fingerprinting

hypervariable minisatellite (VNTR)

22

appears to be normal RNA converted back to DNA using reverse transcriptase then reinserted back into genome

~10% of human genome

short interspersed nuclear element (SINE)

23

might be responsible for mutation because of unequal crossover during meiosis

LINE and SINE

24

LINEs code for what enzyme

reverse transcriptase

25

what are pseudogenes

look like real genes but do not code for any protein hence nonfunctional

26

mitochondrial DNA thought to have risen by?

endosymbiosis because it is a single, circular DNA

27

how are most mitochondrial proteins encoded

by gene in nucleus

28

A student observes the β-globin amino acid sequence, and compares it to the β-globin gene sequence. He finds that some regions are missing in the β-globin protein that is synthesized. The sequences that would be present in the protein that is synthesized are?

exons

29

A research geneticist has identified a tetranucleotide repeat polymorphic marker, that is linked to an autosomal dominant disorder in a family. This marker belongs to the class of

short tandem repeats

30

DNA wound around specific proteins

histone

31

hierarchical levels of chromatin packaging in a human chromosome

double helix --> nucleosome fiber (beads on a string) --> solenoid ---> nucleus

32

importance of metaphase

maximum condensation hence you see all the chromosome ...great for karyotyping

33

attach to the centromere kinetochores during cell division

microtubules

34

gene absent where

centromere and telomere

35

when p and q arm are of equal length

metacentric chromosome (chromosome 1)

36

when p arm is shorter than q arm

submetacentric chromosome (chromosome 4)

37

when p arm contains little genetic information

acrocentric chromosome (chromosome 1, 14, 15, 21, and 22)

38

largest chromosome
smallest chromosome

1 is largest
21 is smallest

39

when both chromosomes of a pair are derived from same parent

uniparental disomy

40

inactivated and condensed X chromosome

barr body (in females)

41

is the same X chromosome inactivated in all descendants of that cell or nah

it is!

42

X-inactivation is regulated by a region called ______ that has the gene, ______ involved in inactivation

X-inactivation center (Xic)

XIST gene

43

XIST RNA coats one of the X-chromosome resulting in...

transcription interference

44

females are said to be mosaic because

of X-inactivation

45

what is locus of a gene

location on the chromosome

46

Autosomal dominant disorders begin with
Autosomal recessive disorders begin with
X-linked disorders begin with
Mitochondrial disorders begin with

1
2
3
5

47

what is significant the p arm on acrocentric chromosome

it has satellite structures

48

what does the mushroom alpha amanatin

RNA pol II