QUICK! Which of the following is the best description of the plasma membrane’s basic structure? Question 1 options:

a phospholipid layer and a protein layer

a phospholipid bilayer with proteins embedded in the layers

a hydrophilic head and a hydrophobic tail

a protein bilayer with phospholipids embedded in the layers

Which of these statements is correct about plastic and concrete? a) both plastic and concrete are minerals because they are natural, solid materials. b) both plastic and concrete are not minerals because they are made by humans. c) plastic is a mineral because it has a definite crystal structure but concrete is not a mineral because it is organic. d) plastic is not a mineral because it is not formed under the ground but concrete is a mineral because it has a definite composition.