Complete the sentences to describe how nitrogen bases pair up in DNA. Adenine always pairs with
Cytosine always pairs with
.

The diagram shows a fossil of an ancient whale skull and a skull of a present-day whale. the ancient whale is extinct and is believed to be an ancestor of the present-day whale. what do these skulls most likely show that supports darwin’s theory of evolution? all populations can adapt and survive. only some organisms have a common ancestor. populations change slowly over time. populations rapidly become extinct.

Astudent is looking through a microscope at some cells of an onion root tip. many of these cells are undergoing division since the root tip grows quickly and requires more cells. which cell most recently underwent metaphase? w x y z

In one or two well-crafted paragraphs in your laboratory journal, summarize the process in which normal cells become cancer cells. your paragraph(s) must include each of the terms listed below. underline each term in your writing: