Answer;
-Phospholipids and protein
Explanation;
-The plasma membrane is composed of a phospholipid bilayer arranged back-to-back. It is also covered in places with cholesterol molecules and proteins. The plasma membrane is selectively permeable and regulates which molecules are allowed to enter and exit the cell.
- The membrane is an extremely thin layer of lipids and protein that forms outer boundary of every cell, It controls movement of molecules between the cell and its environment, Participates in joining cells to form tissues and organs and also plays important role in the ability of a cell to respond to changes in the cell's environment.
Are you asking for the definitions?
Answer: osteoporosis
Explanation: Osteoporosis causes bones to become weak and brittle — so brittle that a fall or even mild stresses such as bending over or coughing can cause a fracture.