Sickle-cell anemia is caused when a mutation results in the replacement of glutamate with valine. Which type of mutation is observed here?

a. chromosomal mutation

b. frameshift mutation

c. substitution mutation

Assume that a student is given two different models of bacteria, with one model consisting of big bacteria and the other consisting of small bacteria. How can the student demonstrate the theory of endosymbiosis using the models?

Shrimp that live in the cold waters off Alaska will die if introduced into warm water. One likely reason these shrimp do not survive is that enzymes in the shrimp A. start to replicate B. change shape C. are composed of fat molecules that melt D.

A medical researcher is investigating the chemical and physical properties of substance that she isolated from the surface of charcoal-grilled meat.

The nurse is teaching CPR to a class. Which statement best explains the definition of sudden cardiac death? 1. Cardiac death occurs after being removed from a mechanical ventilator. 2.

In order to be classified in the same species, a group of organisms must be able to do what?

A lunar eclipse occurs when the moon casts a shadow on earth true or false

During the last century, both global temperatures and men's average height have increased. Do these correlated trends mean that the increase in men's height caused the increase in global temperature? yes ___ no ___ Explain why or why not.

Describe the different types of fossil fuels. What makes them nonrenewable?

As the number of rabbits in a community goes up, the number of foxes in the same community goes up. What type of relationship is this?

Which of the following locations would most likely have the most fertile soil