Cells Unit 3

Cell Membrane and Cell Transport

Notes: Cell Membrane Structure The cell or plasma membrane is also known as the ________________________________ since it has 2 layers. It is known as a ______________ ____________ since it is made up of many parts and is not rigid and moves easily. The main function of the cell membrane is to maintain homeostasis by controlling ___________________________ The cell membrane doesn’t let everything through. It is _________________________________and only lets certain things in and out. PHOSPHOLIPID BILAYER FLUID MOSAIC MODEL WHAT GOES IN AND OUT SELECTIVELY PERMEABLE

Cell Membrane Diagram Video – Cell membrane INTEGRAL PROTEINS CARB CHAIN PHOSPHATE HEAD FATTY ACID TAILS PHOSPHOLIPID CHOLESTEROL PERIPHERAL PROTEIN

Osmosis equal greater out in shrink grow Hypertonic solution Hypotonic solution Isotonic solution equal greater Less than water out water in in / out water shrink grow Stay same size

Concentration Gradient Differences in concentration on either side of a membrane.

Hill Diagram Active Transport Goes against the concentration gradient (low to high) – needs energy (ATP) P = Pump – solute (dots) through a protein E = Endocytosis – move into cell E = Exocytosis – move out of cell High/More Low/Less High / More Passive Transport Goes with the concentration gradient (high to low) no energy D = Diffusion – solute (dots) move (Ex: salt) O = Osmosis – water moves F = Facilitated Diffusion – solute (dots) move through protein Low/Less

DIFFUSION – dots such as salt are moving. OSMOSIS - dots can’t move so water moves to dilute the dots FACILITATED DIFFUSION – dots are too big or polar so need to go through a protein Diffusion Osmosis

Which way will things move? Given the pictures below, draw arrows in the correct direction to show what will move. You need 4 different colors to make your key:   Diffusion – Red Facilitated diffusion – Green Osmosis – Blue Pump (active transport) – Purple

Real life scenarios – What will happen???  A saltwater fish is placed into fresh water. What will happen to the cells of this fish? A freshwater fish is placed into a salt water tank. What will happen to the cells of this fish?   Water will move in and the fish’s cells will grow. Water will move out and the fish’s cells will shrink.

Explain the following picture. Salt on a slug will cause water to move out of the slug to dilute the salt on the outside of the body. The slug will dehydrate and die.

Understanding Osmosis & Diffusion (Passive Transport) Hypo = less Hyper = more Iso = same When answering the questions, consider the following information: The oval in each diagram below represents a cell. The black line around the oval is the cell membrane. The space between the dots represents the water (solvent) that the solute is dissolved in. The solute (dots) AND solvent (water) is small enough to pass across the cell membrane. Cell #1 Cell #2 Cell #3

CONCENTRATION DIFFERENCES: The solution outside cell #1 has a/an (higher; LOWER; equal) concentration of solute compared to the solution inside the cell. The solution outside cell #1 is (hypertonic; HYPOTONIC; isotonic) to the solution inside the cell. The inside of cell #1 is (HYPERTONIC; hypotonic; isotonic) to the solution surrounding it. The solution outside cell #2 has a/an (HIGHER; lower; equal) concentration of solute compared to the solution inside the cell. The solution outside cell #2 is (HYPERTONIC; hypotonic; isotonic) to the solution inside the cell. The inside of cell #2 is (hypertonic; HYPOTONIC; isotonic) to the solution surrounding it. The solution outside cell #3 has a/an (higher; lower; EQUAL) concentration of solute compared to the solution inside the cell. The solution outside cell #3 is (hypertonic; hypotonic; ISOTONIC) to the solution inside the cell.

DIFFUSION: If diffusion was to occur to cell #1, in which direction would most of the solute be moving? (into /OUT OF) the cell. If diffusion was to occur to cell #2, in which direction would most of the solute be moving? (INTO /out of) the cell. Describe what happens to the movement of solute for cell #3. THE SOLUTE WOULD MOVE IN AND OUT. Due to the process of diffusion, the solute or dissolved material tries to move from an area of higher concentration into an area of lower concentration (someplace where it can spread out more). According to this statement, which of the above cells would lose the most solute due to diffusion? (CELL #1, CELL #2, CELL #3)

OSMOSIS: If osmosis was to occur in cell #1, which direction would most of the water be moving? (INTO /out of) the cell. Cell #1 should have (lost ; GAINED; stayed the same) mass. If osmosis was to occur in cell #2, which direction would most of the water be moving? (into /OUT OF) the cell. Cell #2 should have (LOST ; gained; stayed the same) mass. If osmosis was to occur in cell #3, which direction would most of the water be moving? (INTO & OUT OF) the cell. Cell #3 should have (lost ; gained; STAYED THE SAME) mass.

WHAT DOES THIS MEAN… Since an animal cell lacks a cell wall, it is important that it be surrounded by a/an (hypertonic; hypotonic; ISOTONIC) solution, so that it does not shrink & shrivel up or swell & rupture due to the effects of osmosis. If red blood cell is surrounded by a hypotonic solution, then the cell would most likely (shrink, SWELL or stay the same size). When plant cells are full of water, the pressure within the cell pushes out onto the cell wall, thus allowing the cell to become more rigid (has turgor pressure). Since this is a good thing for them, plant cells should be surrounded by a/an (hypertonic; HYPOTONIC; isotonic) solution.

SMALL MEMBRANE BOUND BACTERIA LARGER NUCLEUS PLANTS & ANIMALS Prokaryotic vs. Eukaryotic Cells: Prokaryotic cells - ___________________, no nucleus and no _________________________________ organelles. Ex: ___________________________ Eukaryotic cells - __________________, have a _________________ and membrane bound organelles. Ex: __________________________ SMALL MEMBRANE BOUND BACTERIA LARGER NUCLEUS PLANTS & ANIMALS

CELL MEMBRANE DNA CYTOPLASM RIBOSOMES No matter what, all cells have 4 organelles in common: _________________________________ CELL MEMBRANE DNA CYTOPLASM RIBOSOMES

Notes: Cell Theory All living things are made up of one or more ______________. All cells come from _________________________ cells. Cells are the basic unit of structure and function of an organism. CELLS PREEXISTING

How did the first Eukaryotic cells come about? Endosymbiosis Animation

How did the first Eukaryotic cells come about? Endosymbiosis Theory - endo means _________________, symbiotic means ____________________________ so…… Smaller __________________________ entered inside larger prokaryotes. The smaller prokaryote(s) got ________________________ and the larger prokaryote got _______________________________________________. These organelles eventually became the ______________________ and ____________________________ INSIDE RELATIONSHIP PROKARYOTES PROTECTION ENERGY (ATP) MITOCHONDRIA CHLOROPLAST

Cell Specialization STEM CELLS NERVE CELL SPERM CELL FLAGELLUM RED BLOOD CELL NERVE CELL FLAGELLUM

Notes: Organelles ORGANELLE An __________________is a tiny structure that performs a specialized function (or job) in the cell. Ex: nucleus, chloroplast, mitochondria, ribosome, cell membrane, cell wall, vacuole ORGANELLE

CELL WALL Structure & support CELL WALL (in plants only) Membrane Cell Wall Wall around the kingdom – extra support

CHLOROPLAST Site of photosynthesis – uses light to make sugar (glucose) CHLOROPLAST (in plants only) Farmers – use light to grow (make) food

Stores things like water and nutrients VACUOLE VACUOLE Plant – Large central Animals – many small Stores things like water and nutrients Nucleus Vacuole Well – stores water

CELL MEMBRANE Controls what enters and leaves the cell CELL MEMBRANE Knights at the gate– control what goes in and out

MITOCHONDRIA Site of cellular respiration - turns sugar (glucose) into useable energy (ATP) MITOCHONDRIA Chefs– make food useable by cooking it

NUCLEUS NUCLEUS Protects genetic info DNA = King NUCLEUS = Castle Nuclear Envelope DNA = King NUCLEUS = Castle

RIBOSOMES Where proteins are made RIBOSOMES Town workers – make things

PROKARYOTIC VERSUS EUKARYOTIC No membrane bound organelles Has a nucleus Has DNA Has cytoplasm No nucleus Ex: Plants & Animals Has cell membrane Has ribosomes Has membrane bound organelles Ex: Bacteria

Membrane bound organelles PLANT VERSUS ANIMAL chloroplasts nucleus No cell wall ribosomes Membrane bound organelles Large central vacuole cell membrane Small vacuoles cytoplasm Cell wall mitochondria eukaryotic

Microscopes 10 x 10 = 100 How do we see cells and organelles??? _________________________________________________________ - uses 2 lenses and light to magnify an image up to 2000x. Can look at living cells. Total magnification = ocular lens x objective lens Ex: Ocular is 10x and Objective is on 40 x, what is total magnification? _____________________________________ - used to view larger objects. Magnifies up to 50x. Can look at living cells. _____________________________________ - can magnify up to 200,000x but specimen must be dead. Make sure to study your Microscope Lab to learn more about the parts and functions of the microscope. This will be on your test! COMPOUND LIGHT MICROSCOPE 10 x 10 = 100 STEREOMICROSCOPE/DISSECTING SCOPE ELECTRON MICROSCOPE

COMPOUND LIGHT MICROSCOPE