Based on the graph, determine the amount of U-238 that would remain after 4.5 billion years, if the original sample contained 6 grams of pure U-238.

A) 0.75 grams

B) 3 grams

C) 6 grams

D) 12 grams

Interactions between cells always involve a structure known as a

Which best describes the uterus A. it is a musclar organ where a developing offsprings grows B. it is the exertal part of a female genital organs C. it is the birth canal of the female reproductive system D.

Order the different stages of meiosis 1 through meiosis 2

Give three examples of stimuli that your sensory receptors are responding

1. When is it summer in the Northern Hemisphere? when neither pole is receiving the most direct sunlight during an equinox when the Northern Hemisphere is closest to the sun when the Northern Hemisphere is tilted toward the sun

Explain why multicellular organisms require a ventilation system? include reasons on surface area to volume ratio cells depp within the body and number of cells

After teaching a group of students about the standard childhood immunizations given today, the instructor determines that the students need additional teaching when they identify which as a common disease for which immunizations are given?

Around a pond, there is a small population of turtles. Some of them have solid dark brown shells and some of them have yellow and brown shells with yellow spots. Spotted shells are dominant over solid shells.

Catharine beecher believe that woman should spend their energy

A species of cactus has spines. How would biologists explain how a species of cactus with spines evolved from an ancestral cactus species without spines?