4) Xeroderma pigmentosa (XP) is a rare genetic disease caused by defective photorepair mechanisms. Individuals with XP have a 1000-fold higher risk of skin cancer than those without XP. Explain why
individuals with XP have a higher risk of skin cancer. What precautions do you think an individual with
XP must take on a daily basis?

Next pretest: evolution select the correct answer in a laboratory population of flies, the female flies are gray and the males are yellowish gray. biologists observed that all the male flies had an equal chance for reproduction, but the male flies with the brightest colors were more likely to successfully reproduce. what phenomenon could explain such a change? a sexual selection b. disruptive selection c. stabilizing selection d. directional selection

Diabetes is often suspected when glucose shows up in urine tests. use the model to explain how glucose could be present in urine. why do you think this symptom is especially concerning for young people?

Phosgene is a chemical agent that is formed by decomposition of chlorinated hydrocarbon solvents by ultraviolet radiation. a. false b. true