Which element is found in nucleic acids but not in proteins?

carbon

hydrogen

nitrogen

phosphorus

The lactose operon is under both positive and negative regulation. A bacterial cell does not want to waste the energy to synthesize enzymes to degrade an energy source if that energy source is not present therefore, the lactose operon is regulated

13. plants in the phylum Coniferophyta are O fruit-producing O angiosperms O gymnosperms O flowering

Oxygen from the air enters the blood stream at what location?

A genetic tendency toward efficient use of energy that results in below-average energy requirements and increased storage of calories as fat is called

Some scientists believe that sickle-cell anemia is a beneficial mutation because it: increases life expectancy provides immunity to diseases increases resistance to malaria adds new information to DNA

Which is used to make many copies of DNA? A. PCR B. Reverse transcriptase C. Gel electrophoresis D. Nuclear tranfer

Light___. requires a medium to travel is refracted when it bounces off a shiny surface is created by vibrations in electric and magnetic fields moves in longitudinal waves

Skin cancer is to exposure to uv radiation as

What is the function of the sacrum?

In theory the enzymes should work in colder conditions but at a lower rate, why?