Pls help me on this question.

What are two reasons for why a species might disappear from the fossil record?

Which enzyme is responsible for “unzipping" the dna by breaking the hydrogen bonds between the nucleotides?

Sally, age 3 months, has a moist, red, vesicular rash on her cheeks, the backs of her hands, and her arms. her mother said sally was constantly trying to scratch the rash and often has difficulty sleeping. her father has a family history of allergic rhinitis and asthma. discussion questions. 1. review atrophic dermatitis from chapter 3 and discuss the pathophysiology of sally’s symptoms. 2. why is the father’s medical history significant, and what can sally expect as she grows up? 3. discuss the need to limit scratching, and describe practical methods to achieve this.