HT NA

1 năm trước

Có 1 số tế bào mầm của 1 gà trống (2n=78) đều nguyên phân 6 lần và đã nhận của môi trường nguyên liệu tương đương với 19656 NST.Tất cả các tế bào con sau nguyên phân đều trở thành các tinh bào bậc 1.Các tinh trùng được tạo ra đều tham gia thụ tinh với HSTT bằng 3,125%. Xác định a) Số tế bào mầm ban đầu b) Số hợp tử được tạo ra và số NST trong các hợp tử.

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Phạm Hoàng

1 năm trước

Đáp án:

Giải thích các bước giải:a)=> Số tế bào mầm ban đầu là 4.

b)2496(NST)

pchi0802

1 năm trước

Đáp án + Giải thích các bước giải:

`a)`

Gọi `a` là số tế bào mầm ban đầu `(a∈N)`

Có `2n.a.(2^6-1)=19656`

`=> 78.a.63=19656`

`=> a=4`

Vậy ban đầu có `4` tế bào mầm

`b)`

Số tinh bào bậc I là:

`4.2^6= 256` tinh bào bậc I

Số hợp tử được tạo ra là:

`256.3,125% = 8` hợp tử

Số NST có trong các hợp tử là:

`8.2n= 8.78= 624` NST

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