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
<u>The difference between dog and horse teeth are as follows:</u>
- The dental formula of dog is 2 (I3/I3, C1/C1, P4/P4, M2/M3), whereas for the horse it is 2 (I3/I3, C1/C1, P4/P4, M3/M3).
- The total number of teeth in the dog is 42, whereas in the case of the horse it ranges from 40 to 42.
- In the the dog, upper jaw has 2 molar teeth, whereas in the case of the horse, the upper jaw has 3 molar teeth.
<u>The similarities between dog and horse teeth are as follows:</u>
- The most notable similarity in the case of both the animals is that they have the same number of Incisor, Canine, and Premolar in the order of 3, 1, and 4 respectively.
D, Photosynthesis is with plants.