Wild turkeys are dramatically sexually dimorphic; domestic turkeys are far less so. Suppose that female wild turkeys chose males on the basis of expensive traits that indicate disease resistance and that artificial selection for rapid weight gain in domestic turkeys destroys female choice. What would you predict about the evolution […]

Sickle cell anemia is a very severe condition. a) Explain the condition and the alleles of the person with the condition and why it is a serious problem; b) What type of chromosomal disorder causes the condition; c) If the mother is heterozygous for the trait and the father is […]

A cross is made between two E. coli strains: (Hfr arg+?bio+?leu+) x (F? arg??bio??leu?). Interrupted-mating studies show that arg+ enters the recipient last, so arg+ recombinants are selected on a medium containing biotin and leucine only. These recombinants are tested for the presence of bio+ and leu+. The following numbers […]

Explain how to lift the leg. Begin with the pre-central gyrus and end with the leg lifting away from my death grasp. The message from the brain is sent by neurons. How does a neuron send a message from axon hillock to axon terminal? And once it gets to the […]