Dihybrid cross

Q. The phenotypic ratio when a tall plant with purple flowers (TtPp) is crossed with itself is:

1. 9:4:3:1
2. 9:3:3:1
3. 8:5:3:1
4. 9:2:2:2

Q. What is the genotypic ratio obtained when a tall plant with smooth seeds (TtSS) is crossed with a dwarf plant with wrinkled seed (ttss)?

1. TtSs:ttSs = 1:1
2. TtSs:ttss = 1:2
3. ttSS:ttss = 2:3
4. TTSS:ttss = 1:4

Q. A __________ between two individuals results in a ratio of 9 : 3 : 3 : 1 for the four possible phenotypes of progeny.

1. test cross
2. Gregor cross
3. dihybrid cross
4. monohybrid cross

Q.

A woman with blonde curly hair married a man with black soft hair. All their children in the first generation had black soft hair but in the next generation, children had different combinations in the ratio 9:3:3:1. State the law that governs this expression. [2 MARKS]