Đề thi - Đáp án HSG môn Sinh khối 9 2018-2019

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,.

sa

GIA.O DVC

vA DAo

T~O

BENTRE

DE TID CHON HOC SINH GI<:'n

cAp

TiNH LOP 9

TRUNG HOC

co

sa -

NA.M HOC 2018 - 2019

Mon : SINH HOC

Ngay thi: 27/02/2019

ThOi gian : 150 phut (khong k~ phat d~)

Call

1. (4,0 di~m)

a) Hay phat

bieu

nQi dung quy luat phan li

doc

l~p. f)i~u

kien nghiem

dung

cua quy lu~t

phan

li dQcl~p la gi?

b) Giai thich tai sao kh6 c6 th€ tim

ducc

2 nguoi c6 ki€u gen gieng het nhau

tren trai dfrt

,

ngoai tnr tnrong hop tre sinh doi cung tnrng?

c) Thuc hien phep lai P:

8'

AaBbDd x

~

AaBbdd. Bi~t m6i gen quy dinh mot

tinh trang, gen trQi la trQihoan toan

o

Ha

y

xac dinh:

- S6 loai kieu gen va s6 loai kieu hinh (]

Fl.

- Ti 1~kieu gen (]

Fl

giong kieu gen cua b6.

- Ti 1~kieu hinh (] F

1

khac kieu hinh cua me,

Call

2. (4,0 di~m)

Co th€ lai F

1

chua c~p gen Bb

,

m6i gen d~u c6 90 chu ki

xoan,

Gen B c6

cy

1~

<i>AlG</i>

=

1

/

4, gen b c6 X

=

721 nucleotit. Cho rang gen b xufrthien la do gen B bi dQt

bien tao thanh.

a) Hay cho bi~t day la dQtbi~n gen thuQcd~ng nao?

b) Khi c~p gen Bb

t\l'

nhan do

i

thi moi truang nQibao phai cung cfrpbao nhieu

nucleotit m6i lo~i?

c) Theo Ii thuy~t, chu6i axit amin do gen b wa t6ng hgp xong c6 bao nhieu

axit amin?

.

Call

3. (4,0 di~m)

Bi~t r&ngm6i gen quy dinh mQttinh tr~ng va cac gen phan Ii dQc l~p.

d

ca

chua, ti~n hanh hai phep lai nhu sau:

<i>- Phep lai 1: lai gifra cay ca chua qua do</i>

,

trcmv6i cay ca chua qua do

,

dai thu

dugc dai con g6m 89 cay qua do

,

trcmva 29 cay qua yang

,

trcm.

<i>- Phep lai 2: lai gifra cay ca chua qua do</i>

,

trcmv6i cay ca chua qua yang, tron

thu dugc dai con g6m 119 qua do

,

tron; 120 qua yang

,

tron; 40 qua do

,

dai va 39 qua

vang,dai.

a) Hay bi~n lu~n va vi~t sa d61ai cho m6i phep lai.

b)

d

phep lai 1, Ifryng~u nhien 3 cay (] F

1,

xac sufrt dugc 2 cay Yang

,

tron

chi~m ti 1~bao nhieu?

Call

4. (3,0 di~m)

.

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Cau 5. (5,0 di~m)

d

mot ca the dong v~t

,

co

3

t€ bao sinh

due

<i>sa</i>

khai cung ti€n

hanh

nguyen

phan mot s6 IAnbang nhau

,

sau do cit ca cac t€ bao con d€u

buoc

vao giam phan

hinh thanh giao

tu.

Ca hai qua trinh phan bao nay doi hoi moi tnrong cung cAp 1512

nhi€m sic the dan

,

trong do s6 nhi€m sic the dan cung cAp cho qua trinh giam phan

nhieu han s6 nhi€m sic the dan cung cAp cho qua trinh nguyen phan la 24.

a)

Xac

dinh s6 Ian nguyen phan cua t€ bao.

b) Co bao

nhieu

giao nr

duoc

tao thanh sau qua trinh giam phan?

c) S6 nhiem sic the

(y

ki sau I va ki sau II cua qua trinh giam phan

(y

m6i t€

bao la bao

nhieu?

d) T6ng s6 nhiem sic the trong cac t€ bao con

(y

ki giira Ian nguyen phan cu6i

cung la bao

nhieu?

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---HET---t.

<i>sa</i>

GIAo

Dl)C

vA BAo

T~O
BENTRE

HUONG

DAN

cHAM

THI CHQN HQC SINH GIOI

cAP

TiNH LOP 9

TRUNG HQC

co

<i>sa -</i>

NAM HQC 2018 - 2019

Mon : SINH HQC
<i>Ngay thi: 27/02/2019</i>

1

4,0

di~m

2

4,0

di~m

3

4,0

di~m

a)- NQidung: Cac e~p nhan to di truyen da phan ly dQel~p trong qua trinh

phat sinh giao tl1 0,5

- Di~u kien: Cac e~p alen quydinh cac e~p tinh trang khac nhau phai nam

..

.!~~~

m

~

~

~

.

~~P.

_

~~i.~~

~A~

.

!

~

..

t.~~

~

~

..

~?~~~~~

._

~~~~

_ ___ _._

.

:

._

_._

.

.

_

<i>Q.</i>

<i>~</i>

<i>_</i>

<i>?</i>

<i>_</i>

<i>__ __ .</i>

b) -

<i>a</i>

nguoi: 2n = 46 NST => co 23 cap NST 0,5

=> s6 bien di t6

hop

rna

mot

cap b6 my co th~

410

ra la eire ki IOncu th~

223x 223= 246kieu hQPillkhac nhau. 0,5

1-· ::::- ::; ~ ::::: :::: : ::'::.•,..: :::::..:- : : - - - -- - - -- - - - --.-.-.-..- - -+---.-- ---- - -..--..-- -- -.-.

c) P:

0

AaBbDd x ¥AaBbdd

- se

loai kieu gen

<i>a</i>

FI:3 x 3 x 2 = 18

- S6 loai kieu hinh

<i>a</i>

FI:2 x 2 x 2

=

8

- Ti l~ kieu gen

<i>a</i>

FIgi6ng kieu gen cua b6 (AaBbDd)

<i>2/4 x 2/4 x 1/2</i>

=

<i>1/8</i>

a)

-Tong

so nucleotit cua m6i gen: N = 90 x 20 = 1800 (nu) 0,25
- s6 nucleotit m6i loai cua gen B:

<i>AlG =</i> 11<i>4;rna A + G = N/2 = 180012</i>= 900 (nu)

=> A = T = 180 (nu); G = X = 720 (nu). 0,25

- S6 nucleotit m6i loai cua gen b:

<i>X = 721 rna A + X = N/2 = 1800/2 = 900 (nu)</i>

=> A = T = 179 (nu); G = X= 721 (nu). 0,25

- So sanh s6 nucleotit rung loai cua gen B va b:

+ T6ng s6 nucleotit cua 2 gen bang nhau (1)

+Gb-GB=721-720=1;Ab-AB=179-180=-1 (2) 0,25

I:L!

D

l

,

y.~

.

(~

,

~

?:

A~~g

.

!~!'ly

_.

!~~

~._~_.I.!?~~_g_.~~p_.9

.

}

.

~~p.

__

~.~:. __.._

_.._ .

2

:

_

~

.

. _

_ _.

b) - Tong so nu eua e~p gen Bb:

+ ABb= AB+ Ab = 180 + 179 = 359 (nu) 0,25

+ Gsb= Gs + Gb = 720 + 721 = 1441 (nu) 0,25

- S6 nu m6i lo~i moi truemg eung dp:

=> Amt= Tmt= ABb(21 -1) = 359 (nu) 0,5

Gmt= Gmt= GBb(21-1) = 1441 (nu) 0,5

-

c)

·

·

··

S6

·

~utro

·

ng

·

pii~~

-

tfrmARN

-

do

·

ge~

-·

b

·

t6ngh9P:

- ---

.

---

- .

.

-

-

---

.----.-.-..

-

.. ---..--.

.

NARN=Nb:2 = 1800 : 2 = 900 (nu) 0,25

- S6 bQba = 900 : 3 = 300 bQba. 0,25

=> s6 axit amin = 300 - 1 = 299 (aa). 0,5

Cau

a) - Xae dinh tinh trQi l~n.

+

a

phep lai 1: P: d6 x d6 -7 FI89 qua d6 : 29 qua yang ;:::3 1

=>

qua d6 la trQi so v6i qua yang. Quy u6e: A:d6; a: yang 0,25

+

a

phep lai 2: P: tron x tron -7 FI(119 + 120) tron : (40 + 39) dai;:::
3 1

=>

qua tron la trQi so v6i qua dai. Quy u6e:B : tron; b: dai. 0,25

*

Phep lai 1:

+ d6 x d6 7 3 d6 : 1 qua yang 7 Ki~u gen P: Aa x Aa 0,25

+ tron x dai 7100% tron 7 Ki~u gen P: BB x bb. 0,25

=>Ki~u gen eua b6 my la d6,tron (AaBB) va d6, dai (Aabb)

- Sa d6 lai: P: AaBB x Aabb

Di~m
NQi dung

- Ti l~ kieu hinh

<i>a</i>

FIkhac kieu hinh cua my:

<i>1 - (3/4</i> x <i>314</i>x 112)

=

<i>23/32</i> <i>0,5</i>

'---' _.._._ _.._ .

0,5
0,5

Ghi chii

0,5

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---I,.

,

.

*

Phep lai 2:

+ do x vang ~ FI(119 + 40) do: (120 + 39) qua vang = 1 1
~ Ki€u gen cua P: Aa x aa

+ tron x tron ~ FI(119 + 120) tron : (40 + 39) dai = 3 : 1
~ Ki€u gen cua P: Bb x Bb

=> Ki€u gen cua b6, me dem do,tron (AaBb) va vang, tron (aaBb)
- So'db lai:P: AaBb x aaBb

Gp : AB, aB, Ab, ab / aB, ab

FI: 1 AaBB : 2 AaBb : 1 Aabb : laaBB : 2 aaBb : 1 aabb. 0,5
KH: 3 qua do,tron : 1 qua do,dai : 3 qua vang,tron : 1 qua vang, dai 0,5

.

bjTAyjc~Y

·

6F

;:

·

dugc2

·

··

c~y

·

v~ng

:

·

tr6n

·

:3:(i

7

4j2:

···

{3

j

4);;;;9

7

64:

·

····

·

··

·

·

···

··

·

··

0·;

·

5

·

·

·

·

···

-

-

.

Gp: AB, aB / Ab,ab

FI 1 AABb: 2 AaBb: 1 aaBb

KH: 3 qua do,tron 1 qua vang, tron

0,5
0,5

Neu HS chi

neu diroc

ten khong

neu co

ch~
(tning 1 ten
dQt bien x
0,25 d).
- M6i cach~
x 0,75 d
4

3,0

di~m

DQtbien kieu di bQi (2n+ I) hoac the da bQi(3n) hoac dQtbien I~p dean.

<i>- Co' ch~ hinh thanh (2n+ 1): Trong giam phan II</i>

<i>a</i>

b6 hoac me c~p NST
mang gen A khong phan li ~ giao tll n+ 1 (AA), giaoillnay k~t hop voi
giaoilln (A) ~ h9P

nr

2n+ 1 (AAA).

<i>- Co' ch~ hinh thanh 3n: Trong giam phan II</i>

<i>a</i>

b6 hoac me cit ca cac c~p
NST khong phan Ii ~ giao tll 2n (AA),giaoillnay k~t hop voi giaoill
binh thuong n (A) ~ hopill3n (AAA).

<i>- Co' ch~ hinh thanh dQtbi~n I~p doc;tn:do mc dQng Cllacac tac nhan v~t</i>

If,h6a h9C ~ du truc CllaNST

<i>bi</i>

pha va lam I~pdoc;tnmang gen A. Giao
illchua I~p doc;tn(mang 2 alen A) k~t hqp v6'i giao tll binh thuemg A ~
ki€u gen AAA.

0,25

0,25

1,0

1,0

1,0

5

5,0

di~m

a) - G9i x la so NST dan moi truemg cung cap cho nguyen phan.
y la s6 NST dan moi truemg cung c~p cho giam phan.
k la s6 d9t nguyen phan Cllam6i t~ bao (k nguyen duang)
-Theod€:x+y=1512 (I)

va y-x=24 (2)

CQng(1) va (2): 2y = 1536 =>Y= 768 va x = 744.
- BQNST Cllaloai la:

- Theo bai ta c6: x = 3.2n (2k - I); Y = 3.2n.2k
- Ma: y - x = 24 <=> 3.2n.2k - 3.2n.(2k-l) = 24

=> 2n = 24 : 3 = 8

Th~ 2n = 8,Y = 768 vao y = 3.2n.2k=> k = 5

V~y s6 IAnnguyen phan Cllam6i t~ bao la 5 0,5

b)=N~ii

·

l~t€b~osInhd\ic

·

·

d\fc

-

;;;;

;

-

3

-

x

-

ifx4

-

;;;;

--

384

-

giao

-

tfr

..

_

_

._ _.

.

_

·

-

-

--

0;

-

5

---

-

-

.

_

-

._

-_

-

.

_ -

.

- N~u la t~ bao sinh d\lc cai => 3 x 32 x 1 = 96 giao tll 0,5

···

cj=S6NSTtrong

·

k§ sau"Icliagi~mphiin6m6ri€

-

b~o

·

··

j~

-

8

-

NSTk6p

·

··

·

·

-·

0;

-

5···

-- S6 NST trong

Icy

sau II Cllagiam phan

<i>a</i>

m6i t~ bao hi 8 NST dan 0,5

-

d"j"T6ngs6NSTtrongc~ct~b~o&ki

·

gifraciia

-

iln

·

ngu

-

y€n

·

ph~n

·

cu6Tciing

: .

.

_

_

.

.

--- T6ng s6 t~ bao

<i>a</i>

ki gifra CllaIAnnguyen phan thu 5 = 3 . 25 -I= 48 t~ bao

=>T6ng s6 nhi€m s~c th€ = 8 .48 = 384 NST kep

0,25

0,5

0,25
0,5

0,5
0,5

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