Ở cừu xét tinh trạng màu lông gồm lông đen và lông trắng ,tính trạng kích thước lông gồm lông dài và lông ngắn. Cho cừu F1 mang hai tính trạng trên lai với nhau, F2 thu được kết quả sau: 94 cừu lông đen, ngắn 32 cừu lông đen, dài 31 cừu lông trắng, ngắn 11 cừu lông trắng dài Biết rằng mỗi gen quy định 1 tính trạng a)Phép lai trên tuân theo quy luật di truyền nào? b)Xác định kiểu gen, kiểu hình của F1 và viết sơ đồ lai

Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. an incomplete dominance cross is performed between a bird that is homozygous for red feathers and a bird that is homozygous for blue feathers. purple offspring result. then, two of the purple offspring are crossed. according to the punnett square for this cross, how many of the offspring from the second cross will have a feather color that results from incomplete dominance? 1 in 4 2 in 4 3 in 4 4 in 4

Scientists discover two populations of mice on either side of a major river. the two populations have almost identical genes but the mice from one side cannot breed with mice from the other. this is most likely because

Juan and carol were studying invertebrates in biology. they knew that segmented or earth worms preferred a dark, moist habitat. during this lab, they would be investigating the responses of organisms called planaria or dugesia tigrina. these were simple flatworms that still had a one-way digestive system and a very simple nervous system. juan and carol placed the planaria in a petri dish containing cool, distilled water that was partially covered with black paper. they shined a light on the dish. next, they removed the paper and placed a small amount of chicken liver at one end of the dish. they added a few large salt crystals to the water. finally, they added drops of hot water to the cool water in the petri dish. their results can be seen in the data table. according to their experiment, all but one conclusion is valid.