This document summarizes key aspects of cell physiology: - Cells are the basic structural and functional units of the body and come in many types like muscle, nerve, and blood cells. - The cell membrane encloses the cell and regulates what enters and exits. It is made of lipids and proteins arranged in a bilayer. - Organelles like the nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, and peroxisomes perform specialized functions inside the cell. - Mitochondria generate energy for cells through cellular respiration. The endoplasmic reticulum and Golgi apparatus help synthesize and transport proteins and lipids.

1. بسم اللة الرحمن الرحيم

3. Cells as the Living Units of the Body CELLULAR LEVEL - cells are the basic structural and functional units of the human body & there are many different types of cells (e.g., muscle, nerve, blood, and so on)

34. The nuclear membrane is penetrated by several thousand nuclear pores. Large complexes of protein molecules are attached at the edges of the pores so that the central area of each pore is only about 9 nanometers in diameter. Even this size is large enough to allow molecules up to 44,000 molecular weight to pass through with reasonable ease.

39. Differences Between Extracellular and Intracellular Fluids.

71. The nuclear membrane is penetrated by several thousand nuclear pores. Large complexes of protein molecules are attached at the edges of the pores so that the central area of each pore is only about 9 nanometers in diameter. Even this size is large enough to allow molecules up to 44,000 molecular weight to pass through with reasonable ease.