After 3 half lives how much of a radioactive substance will remain

1/16

1/4

1/2

1/8

What happens to DNA when the temperature is increased to near boiling?

A genetically modified variety of tomato is created and approved for human consumption. Which of the following is most likely to not support this?

Choose all the answers that apply. Matter in an ecosystem: must be continuously replenished is part of a closed system is recycled and reused is returned to the earth by decomposers is always decreasing

On average, how long does a persistent cough last after one recovers from pertussis?

Which statement best describes two paths carbon dioxide can take through the carbon cycle?

From where dothe kenetic tiles collect energy

Landscapes will undergo the most chemical weathering if the climate is * A) cool and wet B) warm and wet C) cool and dry D) warm and dry

Why are sharks so successful at what they do?

The nucleus of an atom is comprised of

When the double stranded DNA helix is unwound, two single strands of DNA are formed. These strands have to be stabilized because their hydrophobic bases are exposed to water. The proteins that stabilize the two single strands are called