If the base pairs in a DNA strand were held together with covalent bonds instead of hydrogen bonds, how would cells have to operate differently? New DNA would need to be made each time the strand was opened.
The cell would have to take in and use more energy in order to break the covalent bonds.
Each time the DNA strand opened the cell would need to replace the nitrogenous bases.
The cell could only open and close the DNA strand when it replicated.

Select the correct answer. which mutation is harmful to the organism? a. a mutation allowing moths to camouflage better on blackened tree bark b. a mutation making staphylococcus aureus resistant to the antibiotic methicillin c. a mutation inhibiting human immunodeficiency virus from attaching to and entering the cell d. a mutation causing uncontrolled cell division e. a mutation giving plant leaves a bitter taste to discourage herbivores from eating them

Explain the source of radioactivity in uranium in earth’s crust by which it produces nuclear radiation

Which term describes a normal value for something in the body? a. homeostasis b. set point c. feedback loop d. integration center