Answer: cell membrane
such as water, micro-organism
physical process
simple diffusion, osmosis and filtration
such as potasssium permaganate in water,urea a liver waste diffuses from the body and the kidney help in filtering it out
physiological processs
active transport, phagocytosis and pinocytosis
such as soduim-potassium pump, exocytosis
Explanation: transportation in and out of cell is done in different ways listed above but a barrier to this movement is the cell membrane which is an outer covering of the cell. it protect the cell and only some materials can penetrate the cell membrane e.g micro-organism, water e.t.c. the various physical and physiological processes are the various ways substance cna be liquid, solid or gas are transported within or outside the cell e.g food
Answer:
Evolution provides evidence as to how animals such as birds are related to much older animals. Over time, species evolve and adapt to their surroundings to suit their habitat. Thus many different species pop up. This all doesn't happen in the blink of an eye, though.
