When huge numbers of species die out in a short period of time, it's known as a mass extinction.

a. True

b. False

Since there are no genes coding for carbohydrates and lipids, how do cells produce them?

Jennifer explained that an

The following is a list of events involved in the activation of a cell by a steroid hormone. Which one of the following answers best represents the order in which the steps occur? 1. cellular response to the hormone 2. activation of a gene 3.

40. Intrapulmonary pressure is the A) pressure within the pleural cavity B) pressure within the alveoli of the lungs C) negative pressure in the intrapleural space D) difference between atmospheric pressure and respiratory pressure

In which organelle are the lipid components of the cell membranes assembled

What difference in traits is caused by chromosomes?

What is the difference between a gene and an allele? a. a gene is a form of a trait, and alleles make up genes. b. a gene is a sequence of bases in a dna molecule, and an allele is an alternative version of a gene that codes for the same feature. c.

Microorganisms that catabolize sugars into ethanol and hydrogen gas would most likely be categorized as A) homolactic fermenters. B) anaerobic respirers. C) alcohol fermenters. D) heterolactic fermenters. E) aerobic respirers.

Which of the following sentences is the best example of a hypothesis a. UV radiation does not cause skin cancer. b. chickens lay more eggs when they are happy. c. why does the earth orbit around the sun? d. how many types of organisms are there?

What will most likely result when the jet stream moves south of North Carolina