Lecture Ch13

8/21/2019 Lecture Ch13

1/77

!"#$ &&& '("( )$*+,$+*( -". /01*(22#3"

45-1$(* 67 8(#32#2

45-+9:# :#";

,(.+>$?


2/77

!"#$%#% '"()*#+,)$-@-1A3#. ;-B($(2 C"D

E#1A3#. FG;3$( CH"D


3/77

I"#B-A2 1*3.+,( 2#";A(9,(AA 5-1A3#. ;-B($(2

-2 21(*B2 -". (;;2

(;;

8(#32#2

21(*B

J(*KA#F-K3"

LG;3$(

@-1A3#. M5-2(

C"D

E#1A3#. M5-2(

CH"D


4/77

N-*G3$G1(


5/77

@3B3A3;3+2 ,5*3B323B(2

@3B3A3;3+2 ,5*3B323B(2 ,-**G $5( 2-B( ;("(2 -$ $5(

2-B( A3,-K3"2 O+$ (-,5 3"( B-G ,3"$-#" .#P(*("$

-AA(A(2

gene for eye color(allele for red eyes)

gene for eye color(allele for purple eyes)

Drosophilachromosome II

Homologouschromosomes

(replicated)


6/77

:5( 43",(1$ 3Q MA3#.G

:5( .,/*$#0 -123"( ! #".#,-$(2

:5( !#$%&' () *+,-!./ /01&, () .2'($(,($&,

1*(2("$I ,(AA2 /*$#04C!RH!R7!R($,3D#".#,-$(2

:5( !#$%&' () &4.2 /01& () .2'($(,($&1*(2("$


7/77


8/77

:5( B-S3* (T("$2 #" B(#32#2

8(#32#2 &U

5$2$*$6% %"/,(,7"

8(#32#2 &&U 8#%7"(

9.($2,)0%

%"/,(,7"

)G"-12#2 3Q 53B3A3;3+2 ,5*3B323B(2

4*322#"; 3T(*


9/77

Haploidgametes (n)Sperm EggDiploid

adult(2n)

Diploid (2n)Haploid (n)

Zygote(2n)

MEIOSIS

MITOSIS(duringdevelopment)

Amount of hereditarymaterial reduced by half

Normal amountof hereditarymaterial restored


10/77

Figure 13.7-1

Nuclearenvelope

Replicatedchromosomes

Non-sisterchromatids

Bivalent (4 chromatids from2 homologous chromosomes)

Spindleapparatus Chiasma

In this example,n 3 so 2n 6

Maternal chromosomesPaternal chromosomes

1. Interphase

2n

2. Early prophase I 3. Late prophase I 4. Metaphase I 5. Anaphase I


11/77

Figure 13.7-2

n

n

n

n

n

n

6. Telophase I

and Cytokinesis

7. Prophase II 8. Metaphase II 9. Anaphase II 10. Telophase II

and Cytokinesis


12/77

MITOSIS MEIOSIS

Diploid parent cell Diploid parent cell

Chromosome replication Chromosome replication

2n

2n

2n

2n

2n

2n

2n

n

n

Four haploid daughter cells of meiosis

Two diploid daughtercells of mitosis

Prophase

Metaphase

Anaphase andTelophase

Prophase I

Metaphase I

Anaphase I andTelophase I

Meiosis II


13/77


14/77

V5(*( E3(2 4*322#"; WT(* W,,+*X

IY(* *(1A#,-K3" )#2$(* ,5*3B-K.2 2$-G K;5$AG S3#"(. -A3"; $5(#* ("K*(

A(";$5

V5(" 53B3A3;2 2G"-12(

:?3 1-#*2 3Q "3"92#2$(* ,5*3B-K.2 -*( O*3+;5$ ,A32($3;($5(*

I*( 5(A. $5(*( OG - "($?3*N 3Q 1*3$(#"2

4-AA(. $5( %4-,/7$-"2,* 9$2/*":


15/77

Figure 13.9

1. Condensation 2. Pairing 3. Synapsis (bivalentformation)

4. Partial separationof homologs

Sister chromatids

Homologs

Kinetochores

Cohesinproteins

Break inchromatidDNA

Synaptonemalcomplex

Kinetochoremicrotubule

Chiasma

Bivalent Crossover betweennon-sister chromatids


16/77

:5( Z3A( 3Q 4*322#"; WT(*

/"2+*( 53B3A3;3+2 ,5*3B323B( 2(1-*-K3"

4*322#"; 3T(* 1*3.+,(2

[(? ,3BO#"-K3"2 3Q -AA(A(2 3" $5( 2-B( ,5*3B323B(4*322#"; 3T(*

&2 - Q3*B 3Q 6"-")9 ("9$23#-,)$-

&$ #",*(-2(2 $5( ;("(K, T-*#-O#A#$G 3Q ;-B($(2 1*3.+,(. OGB(#32#2


17/77

8#2$-N(2 #" 8(#32#2U [3".#2S+",K3"

2n 4n- 1n 2

n 1

n 1

n- 1

1. Meiosis I starts

normally.Bivalentsline up in middle ofcell.

2. Nondisjunction

occurswith oneset of homologs.

3. Meiosis II occurs

normally.

4. Aneuploidy results.

All gametes have toomany or too fewchromosomes.


18/77

8-$(*"-A -;( #2 -" #B13*$-"$ Q-,$3* #" $5(

Q*(\+(",G 3Q $*#23BG

Age of mother (years)

IncidenceofDown

syndrome

pernumberof

births

10001

3001

1801 100

1 601

361

251

161

121


19/77

I2(0+-A T2> 2(0+-A *(1*3.+,K3"

WP21*#"; 1*3.+,(. .+*#"; ,%":1,* ("/($019)$- -*(

;*$-"%$5-$ -*( ;("(K,-AAG #.("K,-A $3 3"( -"3$5(*

'("(K,-AAG #.("K,-A $3 $5( 1-*("$

WP21*#"; 1*3.+,(. OG %":1,* ("/($019)$-R $5( Q+2#3" 3Q;-B($(2R 5-T(

I ,5*3B323B( B-N(+1 .#P(*("$ Q*3B $5-$ 3Q 3"( -"3$5(*

I". Q*3B $5-$ 3Q (#$5(* 1-*("$


20/77

:5( M-*-.30 3Q )(0

Asexual reproduction Sexual reproduction

Generation 1

Generation 2

Generation 3

There are only half asmany child-producingoffspring in the sexualpopulation as in theasexual population


21/77

V5G .3(2 B(#32#2 (0#2$X

:5( M+*#QG#"; )(A(,K3" @G13$5(2#2

:5( 45-";#";9/"T#*3"B("$ @G13$5(2#2


22/77

/01(*#B("$-A E(2#;"6> )$-*$ ?#$5 - 1-$53;(" Q*((

131+A-K3" 3Q *3+".?3*B2>

H> E#T#.( $5( 131+A-K3"]

;*3? 2+O;*3+12 #"

-O2(",( -". 1*(2(",(

3Q (T3AT#"; 1-$53;(">

7> I22(22 $5( *-$( 3Q

3+$,*322#"; 3T(* B-"G

;("(*-K3"2>


23/77

M*(.#,K3"2:5( M+*#QG#"; )(A(,K3" @G13$5(2#2

$5( *-$( 3Q 3+$,*322#"; !"## "%&'()*(

:5( 45-";#";9/"T#*3"B("$ @G13$5(2#2 $5( *-$( 3Q 3+$,*322#"; !"## %+, &-)%.(


24/77

Z(2+A$2


25/77

6^> 8(".(A -". $5( '("( &.(-

45-+9:# :#";

,(.+>$?

5_1U``,3BB3"2>?#N#B(.#->3*;`?#N#`J#A(U&AA+2$*-K3"aM#2+Ba2-KT+Bba,A(-">S1;

CC

3.0


26/77

'*(;3* 8(".(A C6cHHd6cc^D

:5( J-$5(* 3Q 83.(*" '("(K,2

45-+9:# :#"; He

5_1U``???>."-YO>3*;`H`;-AA(*G>5$BA


27/77

V5-$ .3 ?( N"3? -O3+$ 5(*(.#$G O(Q3*(

8(".(AX

fA(".(. #"5(*#$-",(

45-+9:# :#"; Hg

h


28/77

8(".(Ai2 ,53#,( d M(-2 C5+,#$ ,4-6#$D

45-+9:# :#"; Hc

45(-1

/-2G $3 ;*3?

'*(? *-1#.AG

M*3.+,( B-"G 2((.2

5_1U``,3BB3"2>?#N#B(.#->3*;`?#N#`J#A(UccaM#2+Ba2-KT+Baj>S1;


29/77

8(".(Ai2 ,53#,( d M(-2 C5+,#$ ,4-6#$D

45-+9:# :#"; Hk

5_1U``???>."-YO>3*;`H`;-AA(*G>5$BA

45(-1

/-2G $3 ;*3?

'*(? *-1#.AG

M*3.+,( B-"G 2((.2

WO2(*T-OA( $*-#$2 ?#$5 $?3.#2K",$ Q3*B2


30/77

8(".(Ai2 ,53#,( d M(-2 C5+,#$ ,4-6#$D

45-+9:# :#"; 7b

5_1U``???>."-YO>3*;`6`-"#B-K3">5$BA

45(-1

/-2G $3 ;*3?

'*(? *-1#.AG

M*3.+,( B-"G 2((.2

WO2(*T-OA( $*-#$2 ?#$5 $?3.#2K",$ Q3*B2

/-2G $3 Q(*KA#F( -*Kl,#-AAG


31/77

8(".(Ai2 (01(*#B("$2 C&D

45-+9:# :#"; 76

hM

J6

JH

ebHH Hbb67>b6 6


32/77

8(".(Ai2 (01(*#B("$ C&D

45-+9:# :#"; 7H

hM

J6

JH

7>b6 6


33/77

8(".(Ai2 (01(*#B("$ C&D

77

hM

J6

JH

70

7700

6 H 6

7000 77


34/77

45-+9:# :#"; 7^

hM

J6

JH gcg Hgg

8(".(Ai2 (01(*#B("$ C&D


35/77

IAA 2(T(" $*-#$2 253?(. 2#B#A-* *(2+A$2

45-+9:# :#"; 7m5_1U``???>."-YO>3*;`H`-"#B-K3">5$BA


36/77

8(".(Ai2 ,3",A+2#3" C&D


37/77

M*#",#1A( 3Q 2(;*(;-K3"

45-+9:# :#"; 7g

70

70

8-A( ;-B($(2

Q(

B-A(;-B($(

2

n

G

n G

nn nG

nG GG


38/77

8(".(Ai2 (01(*#B("$ C&&D

45-+9:# :#"; 7c

hM

J6

JH76m 6b6 6bc 7H


39/77

8(".(Ai2 (01(*#B("$ C&&D

45-+9:# :#"; 7k

hM

J6

JH76m o 6b6 p ^6e

H>kg

6bc o7H p 6^b

6

77

70

00

00773* 70


40/77

8(".(Ai2 (01(*#B("$ C&&D

45-+9:# :#"; ^b

hM

J6

JH76m o 6bc p ^H7

7>6c

6b6 o7H p 677

6

88 ''

8'

883* 8' ''


41/77

8(".(Ai2 (01(*#B("$ C&&D

45-+9:# :#"; ^6

hM

J6

JH

76m 6b6 6bc 7H

7788 00''

708'


42/77

45-+9:# :#"; ^H

87 80 '7 '0

87

80

'7

'0

8-A( ;-B($(2

Q(B-A(;-B(

$(2

708'

708'


43/77

8(".(Ai2 ,3",A+2#3" C&&D?." /(#-9#/*" $> #-0"/"-0"-7 ,%%$(72"-7d

;("(2 Q3* 2(1-*-$( $*-#$2 2(;*(;-$(

#".(1(".("$AG .+*#"; ;-B($( Q3*B-K3">

45-+9:# :#"; ^7


44/77

Test CrossHomozygous

recessive parentParent of known phenotype

but unknown genotype

Offspring predicted if unknownparent is heterozygous

at both genes

Offspring predicted ifunknown parent is

homozygous dominantat both genes

All

All

All

Couldb

e Couldbe


45/77

:5( 45*3B323B( :5(3*G 3Q &"5(*#$-",(:5( 9.($2$%$2" 7."$(4 $> #-."(#7,-9"

I*32( 3+$ 3Q )+_3" -". f3T(*#2 ,-*(Q+A

3O2(*T-K3"2 3Q B(#32#2

&$ 2$-$(2 $5-$ ,5*3B323B(2 -*(

43B132(. 3Q 8(".(A2 5(*(.#$-*G .($(*B#"-"$2

V5-$ ?( "3? ,-AA ;("(2


46/77

Rrparent

Chromosomes replicate

Meiosis II

Meiosis I

Gametes

Recessive allelefor seed shape

Dominant allele

for seed shape

Allelessegregate

PRINCIPLE OF SEGREGATION:Pairs of alleles are separatedduring meiosis in the formation of gametes.


47/77

:(2K"; $5( 45*3B323B( :5(3*G:53B-2 @+"$ 83*;-"i2

/01(*#B("$2

Z(. (G(2 -2 $5( ?#A.

$G1( Q3* (G( ,3A3*

V5#$( (G(2 -2 -

B+$-K3"


48/77

83*;-"i2 *(,#1*3,-A ,*322(2


49/77

83*;-"i2 *(,#1*3,-A ,*322(2


50/77

/0$(".#"; 8(".(Ai2 Z+A(2

'("(2 4-" f( j3,-$(. 3" $5( )-B(

45*3B323B(

:5( 15G2#,-A -223,#-K3" 3Q $?3 3* B3*( ;("(2Q3+". 3" $5( 2-B( ,5*3B323B(

&2 ,-AA(. *#-@,6"


51/77

Meiosis II

Crossing overduring meiosis I

Recombinant chromosomes


52/77

j#"N-;( 8-11#";(a)Mapping genetic distance (b)Constructing a genetic map

Yellow bodyWhite eyes

Singed bristles Singed bristles

Yellow bodyWhite eyes

Frequency ofrecombinant offspringcorrelates directly withthe distance betweentwo genes; 19.6%recombinant offspring,for example, translatesto 19.6 map units(centiMorgans, cM).

Thesedistancesare in cM


53/77

JA3?(* ,3A3* 3Q ,-*"-K3"2U

I ,-2( 3Q OA(".(. #"5(*#$-",(X

45-+9:# :#"; m7

h


54/77

I ,*322 O($?((" 1#"N q3?(*2

45-+9:# :#"; m^

h

6 H 6


55/77

I ,*322 O($?((" 1#"N q3?(*2

45-+9:# :#"; mm

h

6 H 6

8' 8'

8' ''88


56/77

4-*"-K3" q3?(* ,3A3* .(B3"2$*-K";

#",3B1A($( .3B#"-",( #" ;("(K, #"5(*#$-",(

45-+9:# :#"; me

M#"N JH ;("(*-K3" ,*322

Z

Z

*

*

ZZ

Z*

*Z

**

/;;2 3Q Q(B-A(

M#"N q3?(* CZ*D)1(*B 3Q B-A(

M#"N q3?(* CZ*D


57/77

IAA(A(2 3Q IfW OA33. ;*3+1 253?

,3.3B#"-"$ #"5(*#$-",(

45-+9:# :#"; mg

h9:9: 9;9;

9:9;


58/77

IfW fA33. '("3$G1(2 -". M5("3$G1(2

45-+9:# :#"; mc

fA33. :G1( '("3$G1( I"K;("

I 9:9:3* 9:9 @+B-" 2N#" ,3A3* -". 5(#;5$

45-+9:# :#"; eH


63/77

45-+9:# :#"; e7

I-fO4, h I-fO4,


64/77

[-$+*( -". [+*$+*(U :5( /"T#*3"B("$-A

&B1-,$ 3" M5("3$G1(I ;("3$G1( ;#T(2 - *-";( 3Q15("3$G1#, 1322#O#A#K(2 .+($3 ("T#*3"B("$-A #"q+(",(2

:5#2 15("3$G1#, *-";( #2,-AA(. $5( -$(2 $> (",9)$-Q3* - ;("3$G1(

45-+9:# :#"; e^


65/77

'("(K, &"5(*#$-",( #" @+B-"

45-+9:# :#"; em

5_1U``,3BB3"2>?#N#B(.#->3*;`?#N#`J#A(U8-*#-.(8(.#,#j3+#2h&&&>S1;


66/77

43BB3" 5+B-" $*-#$2 #" $(0$O33N2I_-,5(. (-*A3O(

@#$,55#N(*s2 $5+BO

:3";+( *3AA#";V#.3?s2 1(-N

45-+9:# :#"; ee

5_1U``+.(A>(.+`tB,.3"-A.`BG$5(-*A3O(>5$BA


67/77

M(.#;*(( I"-AG2(2Z(,3;"#F( #"5(*#$-",( 1-_(*"2 3Q 15("3$G1#,

$*-#$2 OG B-11#"; 15("3$G1(2 3" $3 - Q-B#AG

$*(( -,*322 ;("(*-K3"2

45-+9:# :#"; eg


68/77

M(.#;*(( I"-AG2(2IfW OA33. $G1(2 #" BG Q-B#AG

45-+9:# :#"; ec

I

II

I W WW

IWIIf

If

I

If I

W W

W


69/77

:5( Z3G-A J-B#AG 3Q r+((" u#,$3*#-

45-+9:# :#"; ek

5_1U``A3,>;3T`1#,$+*(2`*(23+*,(`1;->bH^ck`


70/77

@(B315#A#- .(2,(".(. $5*3+;5 $5(

.(2,(".-"$2 3Q r+((" u#,$3*#-

45-+9:# :#"; gb

M*#",( IAO(*$

5_1U``,3BB3"2>?#N#B(.#->3*;`?#N#`J#A(v7I/B3lA#->1";

J(B-A( ,-**#(*

!"-P(,$(. B-A(

IP(,$(. B-A(r+((" u#,$3*#-


71/77

&"5(*#$-",( M-_(*" 3Q @(B315#A#-

g6

!"-P(,$(. B-A(

IP(,$(. B-A(


72/77

&"5(*#$-",( M-_(*" 3Q @(B315#A#-

gH

hn hn

hnhnhnhn

hn hn

hn

J(B-A( ,-**#(*

!"-P(,$(. B-A(

IP(,$(. B-A(


73/77

&"5(*#$-",( M-_(*" 3Q @(B315#A#-

g7

hn hn

hnhnhnhn

hn hn

hn

J(B-A( ,-**#(*

!"-P(,$(. B-A(

IP(,$(. B-A(


74/77

@+"K";$3"i2 E#2(-2(

45-+9:# :#"; g^

5_1U``A3,>;3T`1#,$+*(2`*(23+*,(`,15>7,67Hge`


75/77

@+"K";$3"i2 E#2(-2(

45-+9:# :#"; gm

!"-P(,$(. B-A(

IP(,$(. B-A(

!"-P(,$(. Q(B-A(

IP(,$(. Q(B-A(


76/77

8(".(A#-" 1-_(*"2 #" 5+B-" ;("(K,2)#,NA(9,(AA .#2(-2(

IAO#"#2B

E*G 3* ?($ (-*?-04G2K, lO*32#2

45-+9:# :#"; ge


77/77

J#T(9B#"+$( Z(13*$6> V#$53+$ A33N#"; -$ G3+* "3$(2R ?5-$ ?-2 B32$

B(B3*-OA( 3* 2$-".2 3+$ #" G3+* B#". -O3+$

$3.-Gi2 ,A-22X

H>

V5#,5 2+OS(,$C2D`$31#,C2D *(B-#" +",A(-* #" $3.-Gi2

A(,$+*(X

Documents

Lecture Ch13