Glucose is an example of a___________.

Name two functions carried out by carbohydrates.

Name the 2 major Nucleic Acids

What is the primary function of DNA?

What are the monomers of proteins?

An enzyme is a __________ _________.

What type of macromolecule is this?

CELL MEMBRANE Transport

Cell Membrane FUNCTION- Regulates what enters and leaves the cell and also provides protection and support Concentration: Mass of solute/volume of solution Grams/liter

2 Main Types of Transport 1. Passive Transport Examples: Diffusion Osmosis Facilitated Diffusion 2. Active Transport Endocytosis Exocytosis

Diffusion Molecules move from an area of high concentration to an area of low concentration. Diffusion requires NO ENERGY because it is based on random particle movement High Conc.

DIFFUSION

“Please Don’t Stop the Movement” “I wanna take you away from a crowded place to a place where we can all stay You just have to move it, we say you diffuse it Keep on moving to it, please don’t stop the please don’t stop the movement” http://www.youtube.com/watch?v=cDO_-DH8PcE Minute 1:18

Diffusion: High to Low Concentration No energy required

Osmosis Diffusion of water through a selectively permeable membrane Selectively Permeable- some substances can pass while other substances cannot (allows bigger molecules to pass)

WHY is the cell membrane selectively permeable? Because of the hydrophobic core formed by the phospholipids tails

Osmosis  think WATER

Facilitated Diffusion Movement of specific molecules across cell membranes through protein channels

For example, glucose uses a protein channel to cross the cell membrane.

Active Transport

Active transport Materials move against the concentration gradient from low concentration to high concentration REQUIRES ENERGY in the form of ATP. Carried out by transport proteins and pumps

Active Transport.. Getting

Active Transport: Low to High Concentration REQUIRES ENERGY

REVIEW Which type of transport deals with the movement of WATER? Which type of transport goes from low to high concentration? Does it require energy? Which type of transport goes from high to low concentration? Does it require energy? What does it mean to be selectively permeable? Why is the cell membrane considered selectively permeable?

TIME FOR TONICITY!

just remember that ...

TONICITY OF A SOLUTION ISOTONIC SOLUTION: The tonicity of a solution will affect the size & shape of cells: ISOTONIC SOLUTION: solution concentration is equal on both sides of the membrane . There is no net concentration difference across the cell membrane Water moves back and forth, but there is no net gain or loss of water.

the cell stays the same

TONICITY OF A SOLUTION A HYPERTONIC SOLUTION MEANS : LESS SOLUTE, MORE WATER IN THE CELL & MORE SOLUTE, LESS WATER OUTSIDE THE CELL The solution outside the cell is more concentrated than inside. There is more water inside the cell and the water will move OUT of the cell. This causes the cell to shrink *Memory Trick... Hyper people get skinny!

                                                                                                                                                        the cell shrinks

TONICITY OF A SOLUTION A HYPOTONIC SOLUTION MEANS : MORE SOLUTE, LESS WATER INSIDE THE CELL & LESS SOLUTE, MORE WATER OUTSIDE THE CELL The concentration inside the cell is more concentrated than outside. Therefore there is more water outside of the cell, and water will move into the cell. This will cause the cell to swell. *Memory Trick... Hippos are FAT!

the cell expands or bursts

ENDOCYTOSIS Endo = IN Process by which cells absorb molecules (such as proteins) by engulfing them

Type of Endocytosis 2. Pinocytosis (cell-drinking) 1. Phagocytosis (cell-eating) Process in which phagocytes engulf and digest microorganisms and cellular debris; an important defense against infection (white blood cells!) 2. Pinocytosis (cell-drinking) The ingestion of liquid into a cell by the budding of small vesicles from the cell membrane. 3. Receptor-mediated endocytosis Process in which the cell engulfs certain particles like CHOLESTEROL.

Exocytosis- (opposite of endo) EXO = exit Process by which the cell release substances from the cell via vesicles.

Working Together

Conclusion Questions-(Must write the questions or re-state the questions in your answers) 1. What happened to the bears when placed in de-ionized water? Why? 2. What happened to the bears when placed in tap water? Why? 3. What happened to the bears when placed in salt water? Why? 4. What do you think would have happened to the bears if, after the last day, they were ALL placed in de-ionized water? Why? 5. Write a paragraph (at least 8 good sentences) which explains the results of this experiment using the concept of osmosis. Think about how much swelling can occur (equilibrium) Include your specific data & use appropriate tonicity terms to explain your results and support conclusions.