Which of these statements about nucleosomes are correct?

a. The histones H2A, H2B, H3, and H4 make up the nucleosome octamer that binds DNA.
b. Most histones are small (less than 150 amino acid residues), basic proteins rich in Lys and Arg.
c. DNA binding to histones has the same effect as positive supercoiling.
d. Degradation of linker DNA yields DNA fragments of about 200 bp.
e. Partial enzymatic digestion of chromatin results in DNA fragments of about 103 bp.

For a comparative or experimental investigation, scientists often make a testable about a scientific question, and then they test it in the investigation. a.control b.hypothesis c.procedure d.system

The transport tubes from food came down the plant are called?

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.