D\u00f9 th\u1eddi gian l\u00e0m b\u00e0i nh\u01b0 nhau, d\u1ea1ng c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan gi\u1eefa c\u00e1c m\u00f4n thi l\u1ea1i kh\u00e1c xa nhau g\u00e2y m\u1ea5t c\u00f4ng b\u1eb1ng cho th\u00ed sinh.<\/strong><\/em><\/h5>\n

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M\u1ea5y h\u00f4m nay d\u01b0 lu\u1eadn c\u1ea3 n\u01b0\u1edbc c\u00f3 nhi\u1ec1u \u00fd ki\u1ebfn v\u1ec1 \u0111\u1ec1\u00a0thi THPT qu\u1ed1c gia\u00a02018 d\u00e0i v\u00e0 kh\u00f3. T\u00f4i xin \u0111\u01b0\u1ee3c g\u00f3p m\u1ed9t \u00fd ki\u1ebfn kh\u00e1c v\u1ec1\u00a0\u0111\u1ec1 thi\u00a0n\u0103m nay, \u0111\u00f3 l\u00e0 s\u1ef1 kh\u00f4ng th\u1ed1ng nh\u1ea5t v\u1ec1 d\u1ea1ng c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan gi\u1eefa c\u00e1c m\u00f4n th\u00e0nh ph\u1ea7n trong c\u00e1c t\u1ed5 h\u1ee3p thi khoa h\u1ecdc t\u1ef1 nhi\u00ean v\u00e0 khoa h\u1ecdc x\u00e3 h\u1ed9i.<\/p>\n

Hi\u1ec7n t\u1ea1i c\u00f3 2 d\u1ea1ng c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan:<\/p>\n

D\u1ea1ng 1 l\u00e0 c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan ch\u1ec9 c\u00f3 1 \u0111\u00e1p \u00e1n \u0111\u00fang.<\/p>\n

V\u00ed d\u1ee5:\u00a0<\/i>M\u1ed9t lo\u00e0i th\u1ef1c v\u1eadt, alen A quy \u0111\u1ecbnh th\u00e2n cao tr\u1ed9i ho\u00e0n to\u00e0n so v\u1edbi alen a quy \u0111\u1ecbnh th\u00e2n th\u1ea5p; alen B quy \u0111\u1ecbnh qu\u1ea3 ng\u1ecdt tr\u1ed9i ho\u00e0n to\u00e0n so v\u1edbi alen b quy \u0111\u1ecbnh qu\u1ea3 chua.<\/p>\n

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Cho c\u00e2y th\u00e2n cao, qu\u1ea3 ng\u1ecdt (P) t\u1ef1 th\u1ee5 ph\u1ea5n, thu \u0111\u01b0\u1ee3c F g\u1ed3m 4 lo\u1ea1i ki\u1ec3u h\u00ecnh, trong \u0111\u00f3 c\u00f3 54% s\u1ed1 c\u00e2y th\u00e2n cao, qu\u1ea3 ng\u1ecdt. Bi\u1ebft r\u1eb1ng 1 kh\u00f4ng x\u1ea3y ra \u0111\u1ed9t bi\u1ebfn. Ph\u00e1t bi\u1ec3u n\u00e0o sau \u0111\u00e2y \u0111\u00fang?<\/p>\n

A. Trong s\u1ed1 c\u00e1c c\u00e2y th\u00e2n th\u1ea5p, qu\u1ea3 ng\u1ecdt \u1edf F , c\u00f3 3\/7 s\u1ed1 c\u00e2y c\u00f3 ki\u1ec3u gen \u0111\u1ed3ng h\u1ee3p t\u1eed v\u1ec1 c\u1ea3 2 c\u1eb7p gen.<\/p>\n

B. Qu\u00e1 tr\u00ecnh gi\u1ea3m ph\u00e2n \u1edf c\u00e2y P \u0111\u00e3 x\u1ea3y ra ho\u00e1n v\u1ecb gen v\u1edbi t\u1ea7n s\u1ed1 20%.<\/p>\n

C. F1 c\u00f3 t\u1ed1i \u0111a 9 lo\u1ea1i ki\u1ec3u gen.<\/p>\n

D. F1 ch\u1ec9 c\u00f3 m\u1ed9t lo\u1ea1i ki\u1ec3u gen quy \u0111\u1ecbnh ki\u1ec3u h\u00ecnh th\u00e2n cao, qu\u1ea3 chua.<\/p>\n

D\u1ea1ng 2 l\u00e0 c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan c\u00f3 nhi\u1ec1u l\u1ef1a ch\u1ecdn.<\/p>\n

V\u00ed d\u1ee5:\u00a0<\/i>M\u1ed9t lo\u00e0i th\u1ef1c v\u1eadt, x\u00e9t 3 c\u1eb7p gen n\u1eb1m tr\u00ean 2 c\u1eb7p nhi\u1ec5m s\u1eafc th\u1ec3; m\u1ed7i gen quy \u0111\u1ecbnh m\u1ed9t t\u00ednh tr\u1ea1ng, m\u1ed7i gen \u0111\u1ec1u c\u00f3 2 alen v\u00e0 c\u00e1c alen tr\u1ed9i l\u00e0 tr\u1ed9i ho\u00e0n to\u00e0n.<\/p>\n

Cho hai c\u00e2y \u0111\u1ec1u c\u00f3 ki\u1ec3u h\u00ecnh tr\u1ed9i v\u1ec1 c\u1ea3 3 t\u00ednh tr\u1ea1ng (P) giao ph\u1ea5n v\u1edbi nhau, thu \u0111\u01b0\u1ee3c F c\u00f3 1% s\u1ed1 c\u00e2y mang ki\u1ec3u h\u00ecnh l\u1eb7n v\u1ec1 c\u1ea3 3 t\u00ednh tr\u1ea1ng.<\/p>\n

Cho 1 bi\u1ebft kh\u00f4ng x\u1ea3y ra \u0111\u1ed9t bi\u1ebfn nh\u01b0ng x\u1ea3y ra ho\u00e1n v\u1ecb gen \u1edf c\u1ea3 qu\u00e1 tr\u00ecnh ph\u00e1t sinh giao t\u1eed \u0111\u1ef1c v\u00e0 giao t\u1eed c\u00e1i v\u1edbi t\u1ea7n s\u1ed1 b\u1eb1ng nhau. Theo l\u00ed thuy\u1ebft, c\u00f3 bao nhi\u00eau ph\u00e1t bi\u1ec3u sau \u0111\u00e2y \u0111\u00fang?<\/p>\n

I. \u1ede F , t\u1ec9 l\u1ec7 c\u00e2y \u0111\u1ed3ng h\u1ee3p t\u1eed v\u1ec1 c\u1ea3 3 c\u1eb7p gen b\u1eb1ng t\u1ec9 l\u1ec7 c\u00e2y d\u1ecb h\u1ee3p t\u1eed v\u1ec1 c\u1ea3 3 c\u1eb7p gen.<\/p>\n

II. \u1ede F , c\u00f3 13 lo\u1ea1i ki\u1ec3u gen quy \u0111\u1ecbnh ki\u1ec3u h\u00ecnh tr\u1ed9i v\u1ec1 2 trong 3 t\u00ednh tr\u1ea1ng.<\/p>\n

III. N\u1ebfu hai c\u00e2y \u1edf P c\u00f3 ki\u1ec3u gen kh\u00e1c nhau th\u00ec \u0111\u00e3 x\u1ea3y ra ho\u00e1n v\u1ecb gen v\u1edbi t\u1ea7n s\u1ed1 40%. IV. \u1ede F , c\u00f3 18,5% s\u1ed1 c\u00e2y mang ki\u1ec3u h\u00ecnh tr\u1ed9i v\u1ec1 1 trong 3 t\u00ednh tr\u1ea1ng.<\/p>\n

A. 1. B. 4 C. 2 D. 3<\/p>\n

Hai v\u00ed d\u1ee5 n\u00e0y \u0111\u01b0\u1ee3c d\u1eabn t\u1eeb c\u00e2u 107 v\u00e0 112, m\u00e3 \u0111\u1ec1 201, m\u00f4n Sinh h\u1ecdc thu\u1ed9c t\u1ed5 h\u1ee3p thi khoa h\u1ecdc t\u1ef1 nhi\u00ean n\u0103m 2018.<\/p>\n

D\u1ea1ng 1 ch\u1ec9 c\u00f3 1 \u0111\u00e1p \u00e1n \u0111\u00fang n\u00ean th\u00ed sinh ch\u1ec9 c\u1ea7n gi\u1ea3i 1 l\u1ea7n, n\u1ebfu may m\u1eafn c\u00f3 \u0111\u00e1p \u00e1n l\u00e0 c\u00e2u A th\u00ec th\u00ed sinh kh\u00f4ng c\u1ea7n ph\u1ea3i gi\u1ea3i c\u00e1c c\u00e2u B, C, D n\u1eefa.<\/p>\n

D\u1ea1ng 2 bu\u1ed9c th\u00ed sinh ph\u1ea3i gi\u1ea3i t\u1ea5t c\u1ea3 c\u00e1c ph\u00e1t bi\u1ec3u I, II, III, IV t\u1eeb \u0111\u00f3 m\u1edbi bi\u1ebft c\u00f3 bao nhi\u00eau ph\u00e1t bi\u1ec3u \u0111\u00fang.<\/p>\n

Nh\u01b0 v\u1eady v\u1ec1 nguy\u00ean t\u1eafc, \u0111\u00e2y l\u00e0 4 c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan nh\u1ecf \u1edf trong 1 c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan l\u1edbn. Do \u0111\u00f3 th\u1eddi gian \u0111\u1ec3 gi\u1ea3i 1 c\u00e2u d\u1ea1ng n\u00e0y ph\u1ea3i d\u00e0i h\u01a1n, \u0111\u1ed9 kh\u00f3 cao h\u01a1n.<\/p>\n

N\u1ebfu \u0111\u1ec1 thi m\u1ed9t m\u00f4n th\u00e0nh ph\u1ea7n m\u00e0 c\u00f3 t\u1edbi 20 c\u00e2u nh\u01b0 th\u1ebf th\u00ec ngh\u0129a l\u00e0 th\u00ed sinh ph\u1ea3i gi\u1ea3i s\u1ed1 c\u00e2u l\u1edbn h\u01a1n nhi\u1ec1u so v\u1edbi 40 c\u00e2u nh\u01b0 ta th\u1ea5y trong m\u00f4n thi th\u00e0nh ph\u1ea7n.<\/p>\n

Trong \u0111\u1ec1 thi THPT qu\u1ed1c gia 2018, trong t\u1ed5 h\u1ee3p thi khoa h\u1ecdc t\u1ef1 nhi\u00ean, m\u00f4n V\u1eadt l\u00fd kh\u00f4ng c\u00f3 c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan n\u00e0o d\u1ea1ng 2, m\u00f4n H\u00f3a h\u1ecdc ch\u1ec9 c\u00f3 5\/40 c\u00e2u thu\u1ed9c d\u1ea1ng 2, c\u00f2n m\u00f4n Sinh h\u1ecdc c\u00f3 t\u1edbi 20\/40 c\u00e2u.<\/p>\n

\u1ede t\u1ed5 h\u1ee3p thi khoa h\u1ecdc x\u00e3 h\u1ed9i, t\u1ea5t c\u1ea3 c\u00e1c c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan \u1edf c\u00e1c m\u00f4n th\u00e0nh ph\u1ea7n \u0111\u1ec1u thu\u1ed9c d\u1ea1ng 1.<\/p>\n

\u0110i\u1ec1u \u0111\u00f3 cho th\u1ea5y vi\u1ec7c ra bao nhi\u00eau c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan d\u1ea1ng 2 trong m\u1ed9t m\u00f4n th\u00e0nh ph\u1ea7n \u0111\u00e3 kh\u00f4ng \u0111\u01b0\u1ee3c B\u1ed9 GD-\u0110T quy \u0111\u1ecbnh m\u00e0 ph\u1ee5 thu\u1ed9c v\u00e0o \u00fd \u0111\u1ed3 c\u1ee7a th\u1ea7y, c\u00f4 ra \u0111\u1ec1 thi THPT qu\u1ed1c gia.<\/p>\n

Do \u0111\u00f3 n\u1ebfu m\u1ed9t m\u00f4n th\u00e0nh ph\u1ea7n c\u00f3 qu\u00e1 nhi\u1ec1u c\u00e2u h\u1ecfi tr\u1eafc nghi\u1ec7m kh\u00e1ch quan d\u1ea1ng 2 nh\u01b0 \u0111\u00e3 x\u1ea3y ra \u1edf m\u00f4n Sinh h\u1ecdc, m\u00e0 th\u1eddi gian l\u00e0m b\u00e0i v\u1eabn ch\u1ec9 l\u00e0 50 ph\u00fat, th\u00ec qu\u1ea3 l\u00e0 kh\u00f3 kh\u0103n cho th\u00ed sinh v\u00e0 t\u1ea1o ra s\u1ef1 kh\u00f4ng c\u00f4ng b\u1eb1ng n\u1ebfu th\u00ed sinh ch\u1ecdn kh\u1ed1i x\u00e9t tuy\u1ec3n \u0111\u1ea1i h\u1ecdc l\u00e0 kh\u1ed1i B c\u00f3 m\u00f4n th\u00e0nh ph\u1ea7n l\u00e0 m\u00f4n Sinh h\u1ecdc.<\/p>\n

R\u1ea5t mong C\u1ee5c Kh\u1ea3o th\u00ed, B\u1ed9 GD-\u0110T c\u00f3 s\u1ef1 l\u01b0u t\u00e2m v\u1ea5n \u0111\u1ec1 n\u00e0y \u0111\u1ec3 \u1edf m\u00f9a thi n\u0103m sau c\u00f3 s\u1ef1 \u0111i\u1ec1u ch\u1ec9nh cho ph\u00f9 h\u1ee3p, tr\u00e1nh g\u00e2y thi\u1ec7t th\u00f2i cho th\u00ed sinh.<\/p>\n","protected":false},"excerpt":{"rendered":"

D\u00f9 th\u1eddi gian l\u00e0m b\u00e0i nh\u01b0 nhau, d\u1ea1ng c\u00e2u tr\u1eafc nghi\u1ec7m kh\u00e1ch quan gi\u1eefa c\u00e1c m\u00f4n thi l\u1ea1i kh\u00e1c xa nhau g\u00e2y m\u1ea5t c\u00f4ng b\u1eb1ng cho th\u00ed sinh. M\u1ea5y h\u00f4m nay d\u01b0 lu\u1eadn c\u1ea3 n\u01b0\u1edbc c\u00f3 nhi\u1ec1u \u00fd ki\u1ebfn v\u1ec1 \u0111\u1ec1\u00a0thi THPT qu\u1ed1c gia\u00a02018 d\u00e0i v\u00e0 kh\u00f3. T\u00f4i xin \u0111\u01b0\u1ee3c g\u00f3p m\u1ed9t \u00fd ki\u1ebfn kh\u00e1c […]<\/p>\n","protected":false},"author":3,"featured_media":32123,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[19],"tags":[],"yoast_head":"\n