Which of the following describe glands? Check all
that apply
a structure that secretes substances through
a duct
a thin layer that separates or connects
Structures inside the body
a structure that secretes hormones into the
bloodstream
a structure usually made from connective and
epithelial cells

The current thought on the structure of the cell membrane is: a. a static phosphate sandwich of lipids b. a fluid-mosaic of phospholipids and proteins c. a bilayer of proteins with static lipid molecules d. an impermeable bilayer of protein molecules e. a static and permeable phospholipid single layer