How can the 2D gels identify the DNA intermediates associated with a replication origin? Choose combination of correct statements

A. Y-shaped molecule that has three equal length arms will migrate the most slowly of all such molecules derived from a particular DNA fragment

B. A Y-shaped molecule with two very short replicated arms and a large replicated region will migrate very similarly to the unreplicated version of the same DNA fragment. 

C. Y-shaped molecule that results from the almost completely replicated fragment is similar in shape to a linear molecule two times the size of the unreplicated fragment.

#Question id: 2229

#Unit 2. Cellular Organization

The difference between pinocytosis and receptor-mediated endocytosis is that:

#Question id: 2230

#Unit 2. Cellular Organization

Which of these statements about the composition of biological membranes is false?

#Question id: 2231

#Unit 2. Cellular Organization

Membrane proteins:

I) are sometimes covalently attached to lipid moieties.

II) are sometimes covalently attached to carbohydrate moieties.

III) are composed of the same 20 amino acids found in soluble proteins.

IV) move across the membrane unless they are anchored

Which of the following combination is correct?

#Question id: 2232

#Unit 2. Cellular Organization

A GPI anchor

a. serves to attach some proteins to the cytosolic face of the plasma membrane.

b. contains phosphotidylserine.                      

c. may be cleaved to release the protein from the membrane.

d. contains sugar residues in addition to lipid components.

e. contains phosphoethanolamine.

#Question id: 2233

#Unit 2. Cellular Organization

Membrane proteins may interact with biomembranes through

a. covalently attached fatty acid molecules.

b. covalently attached lipid molecules.

c. noncovalent protein-protein interactions.

d. hydrophobic α-helical domains.

e. noncovalent protein-lipid interactions.

#Question id: 2234

#Unit 2. Cellular Organization

Which of the following statement(s) is (are) true of transmembrane proteins?

a. All contains a hydrophobic α helix.

b. Some serve as membrane attachment sites for peripheral membrane proteins.

c. Some contain more than one membrane-spanning domain.

d. All are asymmetrically oriented in the lipid bilayer.