Answer:
A DNA marker
Explanation:
also known as a size standard or a DNA ladder) is loaded into the first well of the gel. The fragments in the marker are of a known length so can be used to help approximate the size of the fragments in the samples.
Answer:
Option 4 depends on the ability to turn towards light.
Explanation:
An animal cell lacking carbohydrates on the external surface of its plasma membrane would likely be impaired in CELL TO CELL RECOGNITION.
Carbohydrates have diverse functions, one of their functions is that they serve as a recognition signal at the surface of cells.
Carbohydrates located on the surface of cells enable cells to recognize and communicate with one another.
B. Positive feedback, it decreases body temperature.
