I cant find ANYTHING about diffusion and osmosis in animal cells for my science project. Can someone help me?

Answer 1

Many plant cells perform osmosis. This is because the osmotic entry of water is opposed and eventually equaled by the pressure exerted by the cell wall, creating a steady state. In fact, osmotic pressure is the main cause of support in plant leaves.

When a plant cell is placed in a hypertonic solution, the water in the cells moves to an area higher in solute concentration, and the cell shrinks and so becomes flaccid [pron. flaxid]. (This means the cell has become plasmolysed - the cell membrane has completely left the cell wall due to lack of water pressure on it (the opposite of turgid)).

Osmosis can also be seen very effectively when potato slices are added to a high concentration of salt solution. The water from inside the potato moves to the salt solution, causing the potato to shrink and to lose its 'turgor pressure'. The more concentrated the salt solution, the bigger the difference in size and weight of the potato chip.

In unusual environments, osmosis can be very harmful to organisms. For example, freshwater and saltwater aquarium fish placed in water with a different salt level (than they are adapted to) will die quickly, and in the case of saltwater fish rather dramatically. Additionally, note the use of table salt to kill leeches and slugs.

Diffusion, is spontaneous spreading of matter (particles or molecules), heat, momentum, or light. Diffusion is one type of transport phenomenon. Diffusion is the movement of particles from higher chemical potential to lower chemical potential (chemical potential can in most cases of diffusion be represented by a change in concentration). It is readily observed, for example, when dried food like spaghetti is cooked; water molecules diffuse into the spaghetti strings, making them thicker and more flexible. It is a physical process rather than a chemical reaction, which requires no net energy expenditure. In cell biology, diffusion is often described as a form of passive transport, by which substances cross membranes.

Diffusion across biological membranes

* Facilitated diffusion
* Ion diffusion through ion channels
* Simple diffusion, not requiring a special protein channel
* Diffusion in the respiratory system - in the alveoli of mammalian lungs, due to differences in partial pressures across the alveolar-capillary membrane, oxygen diffuses into the blood and carbon dioxide diffuses out

Answer 2

Diffusion and osmosis, while similar in some regards, are fundementally different.

I'll start with diffusion, as it's more simple! Diffusion is, in essence, molecules moving around until they're evenly spead out in an area. This generally happens with gases. For example, if you have a sealed box with normal air, and then put in a coloured gas (say blue), you will see the blue gas move from a 'blob' in the corner where you put it, until the same amount of the gas is everywhere in the box, and the entire space is an even shade of blue.

Osmosis is a bit different, and applies very specifically to water. Water will always move, when possible, so that there is the same concentration of water everywhere. For example: Imagine a beaker. You put a semi-permeable membrane vertically down the middle (water can pass through the membrane, but other substances cannot). On one side of the membrane you put some nice thick glucose syrup. It cannot pass through the membrane. On the other side you pour some water. The water will move through the membrane into the syrup, because it is trying to even-out the water concentration. You will then see the level rise on the glucose side, and drop on the water side, as the water moves through (it's very cool to watch!!).

This is where osmosis differs from diffusion. Diffusion results in 'everything' being evenly spread 'everywhere'; whereas osmosis results in the even distribution of water CONCENTRATION, even is this means that one area is essentially 'fuller' than another, like with the beaker.

To give you a cellular context, I suggest reading up in a text book about kidney function and urine production, as that involves osmosis in a big way!

Answer 3

if the egg was soluble to the solution then the concentration of the different solutions you put the eggs in would become equal on the inside and outside of the egg if the concentrations of the solution do not change then diffusion and osmosis didnt occur also osmosis only works with water and diffusion works with all other substances

Answer 4

I remember the definition of osmosis from my 10th grade biology book.

"The movement of water, through a semipermeable membrane, from a region of greater concentration to a region of lesser concentration."

Hope that helps.