Complete the statement to describe the sodium-potassium pump. The sodium-potassium pump moves ions into the cell and ions out of the cell.

Which of the following lines of evidence would best support your assertion that a particular plant is an angiosperm? a) it produces seeds. b) it retains its fertilized egg within its archaegonium. c) it lacks gametangia. d) it undergoes alternation of generations.

What is thought to have caused the mass extinction at the end of the cretaceous period?

If the coding part of an mrna molecule is 1800 nucleotides (bases) in length, this molecule will contain codons and code for a polypeptide that is amino acids long.