Why are DNA primers an important ingredient in a PCR reaction?

DNA polymerase cannot start to copy a DNA molecule without a double-stranded starting point.
Primers create a double-stranded section of DNA.
DNA polymerase cannot start to copy a DNA molecule without a single-stranded starting point.
Primers create a single-stranded section of DNA.

Choose all that apply

Which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements. which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements. the framework of a membrane is a bilayer of phospholipids with their hydrophilic heads facing the aqueous environment inside and outside of the cell and their hydrophobic tails clustered in the center. because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane. the diverse proteins found in and attached to membranes perform many important functions. the kinky tails of some proteins keep the membrane fluid by preventing the component molecules from packing solidly together. membranes include a mosaic, or mix, of carbohydrates embedded in a phospholipid bilayer.

What does the positioning of transcription factors determine?

How does the human body lever work?