Osmosis

Diffusion

Movement of molecules from a region where the molecules are of high concentration to a region where the molecules are of low concentration

Examples of Osmosis in humans

Movement of oxygen into muscle cells for respiration, Movement of carbon dioxide out of the cells

Examples of diffusion in plants

Movement of carbon dioxide into leaves for photosynthesis, movement of oxygen out of the plant

Osmosis

Movement of water molecules from a region of high water concentration to a region of low water concentration across a semi-permeable membrane

Example of osmosis in plants

Movement of water into the roots of the plant from the soil

What is a turgid cell?

a cell in which there is pressure on the cell contents against the cell wall

What causes turgid cells?

When a plant cell has a higher concentration of salt or sugar in its cytoplasm causing water to move into the plant cell through osmosis

What happens to the vacuole and cytoplasm in a turgid cell?

The vacuole and cytoplasm expand

What is plasmolysis

the loss of turgidity in a cell due to loss of water from the cytoplasm

What causes plasmolysis in cells?

When the cytoplasm of the plant cell has a lower concentration of sugar or salt than its surroundings the water moves out of the cell through osmosis.

What happens to the cytoplasm and vacuole in plasmolysis?

They shrink

What happens if the cytoplasm concentration (salt, sugar, etc) is less than the surrounding environment?

Water moves out the cell causing plasmolysis and the plant wilts

What happens if the cytoplasm concentration is greater than the surrounding environment?

Water moves into the plant cell, causing the plant cell to become turgid, giving the plant shape and support

What happens if the cytoplasm concentration is equal to surrounding environment?

Water movement rate and the plants shape and support remain constant

How does osmosis preserve food?

Food is placed on a solution/base of high concentration. Water leaves the microorganisms, killing them from dehyrdation

What is active transport?

the movement of molecules from a region where the molecules are in low concentration to an area where the molecules are in high concentration using energy

Where does active transport take place?

The ileum absorbs glucose molecules by active transport

What is the rate of osmosis?

Speed at which water molecules move from an area of high concentration to an area of low concentration

What factors affect the rate of osmosis?

Temperature, Concentration Gradient, Surface Area

How does temperature affect rate of osmosis?

Higher temperature provides water molecules with more energy, moving them faster

How does concentration gradient affect rate of osmosis?

Higher the difference of concentration between the two regions the higher the rate of osmosis

How does surface area affect rate of osmosis?

The greater the surface area the more area for water molecules to move across the membrane, leading to a higher rate of osmosis.