Shell orientation in snails is due to a maternal effect gene. A true breeding sinistral (recessive) is crossed to a true breeding Dextral (dominant). The offspring from that cross are self-crossed. What will be the expected ratio of shell types? A. All sinistral
B. All Dextral
C. Half sinistral, half Dextral
D. Dextral, 4 sinistral
E. Sinistral, Dextral

The earth consists of a variety of different organisms. despite their diversity, however, some similarities on the structural and metabolic levels may be seen. these similarities can be attributed to a. similarities among organisms in their proteins and nucleic acids. b. the ability of organisms to readily adapt to sudden environmental changes. c. similarities in organisms' habitats and niches. d. the ability of all organisms to interbreed and produce new species.

How does the study of genetic disorders such as pku biologists understand normal alleles?

Asolution of an enzyme and a substrate was placed in a water bath and the temperature of the reaction was raised gradually. the graph shown was plotted at the end of the experiment. what can be concluded from the graph? a) temperature has no effect on the activity of the enzyme. b) the effect of temperature on the enzyme is unpredictable. c) the enzyme shows increased activity up to a certain temperature. d) the activity of the enzyme is inversely proportional to the temperature.