Cellular Transport This is going to show how cells transport substances in and out.

Do Your Cells Eat and Drink? Cells must take in water and nutrients in order to function. Mmm….. The cell must take in sugars, hormones, amino acids, etc. In takes in all things necessary for cellular function. Get input from students on cell shape. Discuss the fact that cells are 3D.

What part of the cell allows it to take in nutrients and water? Also known as….. PLASMA MEMBRANE The CELL MEMBRANE!!!!!! First ask the students if they know the answer. Click to bring in the picture of the cell membrane. Do not discuss all of the labeled structures. You may point out the different proteins (channel, marker, receptor). Or…… PHOSPHOLIPID BILAYER

What is the Cell Membrane Made Of? Proteins and phospholipids Do not discuss individual proteins here. Discuss the structure of the phospholipids (head and tail). It is a fluid membrane. The proteins float through the lipids and it is not solid. It can be described as a “Wall of Crisco”.

What are the Proteins in the Cell Membrane? Carrier Channel Peripheral The students do not need to be tested over this information! Click to bring in each name. Do one at a time so you can discuss. Receptors receive chemical information (hormones)and act like a radio antenna to send information inside the cell. Most hormones do not actually go into the cell. Channel protein bring polar compounds (ex: glucose) into the cell. The compound actually has to fit the shape of the channel. Marker proteins identify the cell. They are the “name tags.” They identify the cell as “self,” so that your body identifies your cells. Integral

SO….. How DO Your Cells Eat, Drink and be Merry? They DO party!

Cells move substances through the cell membrane by a process called transport Two Types of Transport: Passive Transport Active Transport Ask the kids what the word transport means. (To move from one place to another). Cells need to move substances in and out in order to function.

What is Passive Transport? Diffusion Requires no energy from cell. Molecules move from high concentration to low concentration. Molecules move with the concentration gradient. These are the three characteristics of passive transport. Concentration gradient – molecules flow with the movement of molecules. “Goes with the flow” – the different concentrations within a space.

Diffusion How does it work? Have students explain what is happening in the animation. Starts out highly concentrated and moves (diffuses) to achieve equilibrium. You can use the analogy of having all 30 students sitting at one desk. They would all move to even themselves out.

Osmosis The diffusion of water across a semi-permeable membrane. “Water wants to water “stuff” down”

Facilitated Diffusion Diffusion of large or polar molecule through protein channels. “Helped Diffusion”

What would happen to the animal cells in each beaker? 100% Distilled Water 70% Water 30% Dissolved Substances 80% Water 20% Dissolved Substances Ask the students to predict what would happen to the cells in the beaker. You may want to explain solutions first. Dissolved substances would be sugars, salts, ions, etc.

Which way did the water move? 100% Distilled Water 0% dissolved substances 80% H2O 20% “stuff” Have the students predict – and then show the answer. You have to click to get the beaker and the question to show. Why did the cell get so big? Hypotonic solution

Which way did the water move? 80% Water 20% Dissolved Substances 80% H2O 20% “stuff” Predict and show answer. Why did the cell stay the same size? Isotonic solution

Which way did the water move? 70% Water 30% Dissolved Substances 80% H2O 20% “stuff” Predict and show answer. Why did the cell get so small? Hypertonic solution

Let’s look at what happens to your blood cells in the three different solutions: Isotonic (equal) Hypertonic (high) Hypotonic (low)

REVIEW What are the characteristics of passive transport? Explain diffusion. Why does it occur? Explain osmosis. Why does it occur? What is the role of the channel protein in facilitated diffusion? no energy, high to low, and with concentration gradient. Movement of substances across a membrane. To reach equilibrium Diffusion of WATER across a membrane. To reach equilibrium. To help molecules diffuse across.

Even MORE Review! What happens to an animal cell when there are more dissolved substances on the outside of the cell? The inside? When there are equal amounts? Water moves out of the cell, causing it to shrink. Water moves inside the cell, causing it to swell. The cell stays the same size.

Active Transport

How is Active Transport different? Active transport requires energy. Molecules move from low concentration to high concentration Molecules move against concentration gradient. Ask the students what the energy is - ATP

What is this cell doing? Have the students explain what is happening. Point out the arrow. - Endocytosis

Endocytosis Cells bring in large particles using the cell membrane There are 2 types: Phagocytosis Pinocytosis Channel proteins are used to bring in large molecules. Endocytosis is the process of brining particles into the cell. To demonstrate with the use of channels proteins, click on the link at the bottom of the page. You must close the browser window to return to the powerpoint.

Phagocytosis Your white bloods cells also do this. Amoeba Make sure to point out that the diagram is an amoeba, not a human cell. As the “food particle” moves in the cell, it fuses with lysosomes to be digested. Your white bloods cells also do this. This is the ingestion of large particles.

Pinocytosis For animation, point out to the students that the cell doesn’t “spit” the contents out, like it does in the picture. The particles move into the cell and become part of a vacuole. Tiny pockets form along cell membrane, and pinch off into vacuoles inside the cell. Sometimes called “Cell Drinking”

Exocytosis This is how the cell gets rid of waste. The blue particle should have “waste” particles in it, but does not. Make sure this is pointed out to the students. The waste fuses to the cell membrane and is then released into the environment. This is how the cell gets rid of waste.

REVIEW How is Active transport different from passive? Complete the chart. What part of the cell is used to bring in particles? How does a cell (including white blood cells) take in LARGE particles? How does a cell take in small or liquid particles? Uses energy, moves against concentration gradient, goes from low to high. Cell membrane Endocytosis – phagocytosis pinocytosis.