Which of the following are example (s) of causes of mass extinctions in Earth's history?

A. changes in sea level

B. All of these are causes of mass extinctions in Earth's history.

C. ice ages

Why do most viral diseases stop at the first step?

A forensic anthropologist documents evidence of past cultures for future generations true or false?

Out of 5 undisturbed horizontal beds of sedimentary rock, we can say that A. the top layer is oldest B. the lowest layer is oldest C. there is no way of knowing which is oldest D. the 2nd and 3rd are younger than the top layer.

The roots nodules of leguminous plants contain a parasitic bacterium it is true or false

Which level in a food web contains the highest amount of total available energy? A primary consumer B. Secondary consumer C. decomposer D. producer

What would you need to do to make a drum have a louder sound

Suppose jennifer has a pcr product that contains three dna fragments of 300, 700, and 1000 base pairs in length. she separates the three fragments using gel electrophoresis.

Assume a normal female with a resting tidal volume of 400 ml, respiratory rate of 13 breaths/min, and dead space of 125 ml. When she exercises, which of the following scenarios would be most efficient for increasing her oxygen delivery to the lungs?

Why are people who have poor dna repair mechanisms at greater risk for cancer development? select one: a. their cancers are usually resistant to chemotherapy. b. they have greater exposure to environmental carcinogens. c.

A cell in prophase ii of meiosis has 12 chromosomes. how many chromosomes will be present in a cell from the same organism if it were in prophase of mitosis? prophase i of meiosis