Do Now l List all the different types

Do Now l List all the different types of cells you can think of. l What do all of these cells have in common?

Cells & Microscopes

Development of the Cell Theory

What is a cell? l. A cell is the basic unit of life l Organisms can be unicellular and multicellular, but all living things are made of CELLS!

History of the Cell l Robert l Anton Hooke van Leeuwenhoek l Matthias l Rudolf Schleiden & Theodor Schwann Virchow

The Cell Theory l All living things are made of cells l Cell is the basic unit of living things l All cells come from pre-existing cells

Two classes of cells Prokaryote Eukaryote

All cells have… l Plasma membrane l Genetic material l Cytoplasm l Ribosomes (make proteins)

A B 1. Identify the prokaryotic and the eukaryotic cell. 2. Explain why you labeled each diagram as you did. 3. Which of the two cells is more likely to make up your body? 4. Which of the two is most likely a bacteria cell? 5. Is either of the cells from a plant? How do you know?

Sell a cell (part). Create an advertisement selling an organelle. Your ad must include: l A colored, detailed picture l A slogan l A description of l l l Which cells need it? (plant/animal? Eukaryote/prokaryote? All of the above? ) Its function Its structure (what is it made of? What does it look like? How is it designed? ) A reason to buy it (why do I need it? ) Any add-ons or special features A price

Organelles & Cell Parts

The nucleus

Ribosomes – protein factories

ER, Golgi Apparatus, Vesicles

Vacuoles & Lysosomes

Mitochondria

Chloroplast

Plasma membrane l Selectively permeable

Cell Wall

Cytoskeleton l Microtubules or Microfilaments Enables cell to move or change shape l Provide tracks for organelles to move l Make the core of flagella & cilia l

Cytoplasm

Look at your eggies! l 1. CAREFULLY remove eggs from cups l 2. CAREFULLY rinse off any excess stuff l 3. CAREFULLY pat eggs dry and final mass of your eggs. l 4. Calculate percent change in mass ((massf – massi)/massi) *100

Do Now Do you remember which of the biomolecules from chapter 5 make-up cell membranes? LIPIDS! (and proteins) l What is unique about the interaction between lipids and water? HYDROPHOBIC! l Why do you think hydrophobic molecules like lipids make good cell membranes? l

Structure of membrane All cells have a cell membrane!

Plasma Membrane Structure l Made of proteins and phospholipids l l Phosphate head is hydrophilic 2 Fatty acid tails are hydrophobic *Which end is pushed away by water? Which end is attracted to water?

Plasma Membrane Structure Cell membrane is a phospholipid bilayer l boundary between the watery inside and the watery outside of the cell l

Proteins in the Membrane l Proteins perform specific functions in membranes Enzymes carry out chemical rxns l Cell-to-cell recognition l Cell signaling l Transport materials across membrane l

Transport through membrane l Some molecules pass easily, others need energy to “push” them through l 2 types of transport Passive transport l Active transport l

Passive Transport No energy needed! (It just happens)

l http: //www. indiana. edu/~phys 215/lecture /lecnotes/lecgraphics/diffusion 2. gif l Explain what happened

Passive Transport l Diffusion – net movement of particles from high concentration to low concentration l Facilitated diffusion – membrane proteins create a pathway for diffusion

Osmosis l Osmosis – diffusion of water across a membrane l A cell is in a solution Two different solutions, one inside the cell, one outside the cell l Osmosis determined by relative concentrations of the two l

Solutions l Hypertonic l Solution that contains a higher concentration of solute

l Hypotonic l Solution with a lower concentration of solute

l Isotonic l Solutions with the same concentration of solute

What happens if… l An animal cell is placed in a hypertonic environment? l An animal cell is placed in a hypotonic environment? l An animal cell is placed in an isotonic environment?

What happens if… l. A plant cell is placed in a hypertonic environment? l A plant cell is placed in an isotonic environment? l A plant cell is placed in a hypotonic environment?

Back to the eggies l For each of your solutions, state whether you believe it is hypertonic, hypotonic, or isotonic to your egg. l In C-E-R form!

Osmosis • Activity: Copy and complete the chart (full page!). Solution Hypertonic Hypotonic Isotonic Definition Animal Cell Plant Cell (healthy or unhealthy & WHY)

Active Transport Energy (ATP) required!

Active Transport l Active Transport – cell uses energy (ATP) to move molecules through membrane l Usually in opposite direction of diffusion

Active Transport l Transport proteins pump solute across the membrane What organelle supplies the ATP needed for AT? l What chemical reaction produces ATP? l

Transport of Large Molecules l Large molecules have to be packaged in vesicles to move in and out of cells l Exocytosis =out of the cell l Endocytosis = into the cell Phagocytosis = “cell eating” l Pinocytosis = “cell drinking” l http: //www. northland. cc. mn. us/biology/Biology 1111/animations/active 1. swf