A biologist wishes to take a useful gene found in pine trees and introduce it into some bacterial cells. Her experimental procedure is given below.

1. Use a restriction enzyme to cut a gene out of the pine tree DNA.
2. Use a restriction enzyme to cut open a plasmid.
3. Treat the plasmid with DNA ligase.
4. Mix the desired gene and plasmid together.
5. Introduce the plasmid into bacterial cells.
Which steps should be switched in the biologist's procedure?

A. 3 and 4
B. 1 and 3
C. 2 and 3
D. 4 and 5

Use the drop down menus to match each example to the fossil topic discussed then to show how the fossil record gives evidence of evolution

Nucleic acid certain protein cell membranes certain carbohydrates

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.