The correct statements are:
1. 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.
2. The diverse proteins found in and attached to membranes perform many important functions.
5. Because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane.
The pituitary gland secretes follicle stimulating hormone, which acts on the follicles and stimulates them to produce progesterone.
