test2 Flashcards Preview

bio > test2 > Flashcards

Flashcards in test2 Deck (37)
Loading flashcards...
1

metacentric chromosome position

in the middle

2

Submetacentric chromosome

off center

3

Acrocentric

Near one end

4

Telocentric

is at one end

5

what is pleitrophy

a single gene with multiple phenotype effects

6

what is marfan syndrome

-is autosomal dominant
-encodes connective tissue fibrillin
-causes aneurisms, eye defects, weak bones

7

what are the effects of Porphyria Variegata

-red urine, delirium, abdominal pain

8

Amorph

null mutation(loss of function)

9

Hypomorph

reduced expression of gene product(partial loss)

10

Hypermorph

Increased expression of gene function

11

Neomorph

New function of mutant protein

12

Antimorph

New activity that effects wild type function

13

Overview of meiosis (what happens)

chromosomes duplicate once, nuclei divide twice (2N->n)

14

What happens in Prophase 1

Crossing over occurs

15

what happens in prophase 1- leptotene

chromosomes thicken

16

what happens in prophase 1- zygotene

homologous chromosomes enter synapsis
synaptoneal complex forms

17

what happens in prophase 1- pachytene

synapsis is complete
crossing over occurs

18

whats happen in prophase 1- diplotene

synaptic complex dissolves
tetrad of 4 chromosomes is visable

19

what happens in prophase 1- diakinesis

chromatids thicken and shorten

20

what happens in metaphase 1

tetrads line along middle

21

what happens in telophase 1

Nuclear envelope reforms (2 sis chromatids)

22

swyer syndrome

2n=46, XY
don't develop female secondary characteristics

23

Androgen Insensitivety syndrome

2n=46yy
lack of androgen receptors

24

klinefelter syndrome

47, XXY
genatilia and internal male
result of nondisjunction event

25

Turner Syndrome

45XO
female external genetalia + internal
result of nondisjunction event

26

47,XXX syndrome

some phenotypically normal, while some have underdeveloped secondary characteristics

27

47, XYY condition

phenotypically male, usually over 6 f

28

dihybrid cross ratio

9:3:3:1

29

9:7 ratio indicates

complementary gene action

30

9:3:4 ratio indicates

recessive epistatis
(labradors, ee masks effect of B)

31

12:3:1 ratio indicates

dominat epistasis 1
the dominant allege of one gene masks both alleles of the other gene
(grey horses)

32

13:3 ratio indicates

dominant epistasis 2
the dominant allele of one gene masks the dominant allele of the other gene

33

15:1 ratio indicates

Redundant gene
only one dominant allele of 2 genes is necessary to produce phenotype

34

Frans Janssens

observed chiasmata at chromosomes during prophase of meiosis 1

35

T.H Morgan

Suggested chiasmata were sites of chromosome breakage + exchange

36

Creighton/ McClintock

direct evidence that recombinant depends on reciprocal exchange of chromosomes

37

Sturtevant

proposed that recombinant frequencies could be used as a measure to measure distance