1. 1.List the four biomolecules we studied State the function (job) of each bio- molecule. 3. Draw and label an enzyme, substrate, & active site

Are All Cells Alike? All living things are made up of cells. Some organisms are composed of only one cell. Other organisms are made up of many cells. 1. What are the advantages of a one- celled organism? 2. What are the advantages of an organism that is made up of many cells?

Cell Theory 1. All living things are made of cells.1. All living things are made of cells. 2. New cells are produced from existing cells2. New cells are produced from existing cells 3. Cells are the basic unit of structure and function in living things.3. Cells are the basic unit of structure and function in living things.

Prokaryotes vs. Eukaryotes Prokaryotes (bacteria) have no nucleus and very few organelles. DNA is not containedProkaryotes (bacteria) have no nucleus and very few organelles. DNA is not contained Eukaryotes (protists, fungi, plants and animals) larger,more complex,DNA is inside the nucleusEukaryotes (protists, fungi, plants and animals) larger,more complex,DNA is inside the nucleus

ProkaryotesEukaryotes Cell membrane Contain DNA Nucleus Endoplasmic reticulum Golgi apparatus Lysosomes Vacuoles Mitochondria Cytoskeleton DNA is free floating No membrane bound organelles

Compare/contrast prokaryotic cells and eukaryotic cells. Include what they have in common as well as the big differences. Pro no Eu do Quiz

1. What does Pro no mean? 2. What does Eu do mean? 3. What do both eukaryotes and prokaryotes have? Pro no Eu do Quiz

Plant Cells Vs. Animal Cells Some structures are specific to either plant cells or animal cells only:Some structures are specific to either plant cells or animal cells only: –Only plant cells contain: Cell wallCell wall ChloroplastsChloroplasts Large central vacuolesLarge central vacuoles –Only animal cells contain: CentriolesCentrioles

Plant Cells Nuclear envelope Ribosome (attached) Ribosome (free) Smooth endoplasmic reticulum Nucleus Rough endoplasmic reticulum Nucleolus Golgi apparatus Mitochondrion Cell wall Cell Membrane Chloroplast Vacuole

Animal Cells Centrioles Nucleolus Nucleus Nuclear envelope Rough endoplasmic reticulum Golgi apparatus Smooth endoplasmic reticulum Mitochondrion Cell Membrane Ribosome (free) Ribosome (attached)

A.NUCLEAR ENVELOPE-REGULATES WHAT ENTERS AND LEAVES NUCLEUS B. NUCLEOLUS – PRODUCES RIBOSOMES C. CHROMOSOMES - CONTAIN GENETIC MATERIAL (DNA)

Organelle Quiz I 1.Which organelle separates the inside of the cell from the surrounding environment? 2.Which organelle is the energy bank for the cell?

Mitochondria vs. Chloroplasts Mitochondria make energy from chemicals (food molecules)Mitochondria make energy from chemicals (food molecules) Chloroplasts use Chloroplasts use energy from light energy from light through photosynthesis through photosynthesis

ATP - Life’s Energy Currency Energy is released when ATP is hydrolyzed (broken down) to ADP. ATP is restored from ADP and an input of energy. ATP’s energy is used to drive endergonic (energy- requiring) reactions.

…Remember “ATP”? ATP stores energy for cell activities like active transport & movement within the cellATP stores energy for cell activities like active transport & movement within the cell

Cell Membrane Regulates what enters and leaves the cell and provides support and protectionRegulates what enters and leaves the cell and provides support and protection Structure – lipid bilayer with embedded proteinsStructure – lipid bilayer with embedded proteins

Cell Wall Provides support and protection for plant cell wallsProvides support and protection for plant cell walls Made of porous cellulose so it does not regulate what enters and leavesMade of porous cellulose so it does not regulate what enters and leaves

Smooth ER vs. Rough ER Rough ER - ribosomes on the ER make proteins, the ER modifies the proteinsRough ER - ribosomes on the ER make proteins, the ER modifies the proteins Smooth ER - makes lipidsSmooth ER - makes lipids Ribosomes assemble proteinsRibosomes assemble proteins

Cytoskeleton Network of protein filamentsNetwork of protein filaments Maintains shapeMaintains shape Involved in cell movementInvolved in cell movement

Animal CellsPlant Cells Centrioles Cell membrane Ribosomes Nucleus Endoplasmic reticulum Golgi apparatus Lysosomes Vacuoles Mitochondria Cytoskeleton Cell Wall Chloroplasts

Phospholipids Form Biological Membranes

Fluid-Mosaic Plasma Membrane

Cholesterol is wedged between phospholipid molecules in the plasma membrane of animals cells. At warm temperatures, it restricts the movement of phospholipids and reduces fluidity. At cool temperatures, it maintains fluidity by preventing tight packing.

Diffusion through Cell Boundaries Particles move from an area of high concentration to an area of lower concentrationParticles move from an area of high concentration to an area of lower concentration No energy is requiredNo energy is required

For example, if we start with a permeable membrane separating a solution with dye molecules from pure water, dye molecules will cross the barrier randomly. The dye will cross the membrane until both solutions have equal concentrations of the dye. At this dynamic equilibrium as many molecules pass one way as cross the other direction.

Osmosis Diffusion of water through a selectively permeable membraneDiffusion of water through a selectively permeable membrane

Differences in the relative concentration of dissolved materials in two solutions can lead to the movement of ions from one to the other. –The solution with the higher concentration of solutes is hypertonic. –The solution with the lower concentration of solutes is hypotonic. –Solutions with equal solute concentrations are isotonic Osmosis is the passive transport of water

In the absence of other forces, a substance will diffuse from where it is more concentrated to where it is less concentrated, down its concentration gradient. Each substance diffuses down its own concentration gradient, independent of the concentration gradients of other substances.

The solute is more concentrated on the right side. Which side is hypertonic? How will dynamic equilibrium be reached? The solute is more concentrated on the right side. Which side is hypertonic? How will dynamic equilibrium be reached?

Isotonic "ISO" means the same Concentration of solutes (salts) is the same inside and outside of cell.Concentration of solutes (salts) is the same inside and outside of cell. Water flows in and out in equal amountsWater flows in and out in equal amounts No effect on cellNo effect on cell

Hypotonic "HYPO" means less Concentration of solutes is less outside the cell than in.Concentration of solutes is less outside the cell than in. Water flows inWater flows in The cell swell with water and becomes “turgid”The cell swell with water and becomes “turgid”

Hypertonic “Hyper” means more Concentration of solutes is greater outside the cell than insideConcentration of solutes is greater outside the cell than inside Water flows out of cellWater flows out of cell The cell shrivels and may die.The cell shrivels and may die. This is why it is dangerous to drink sea waterThis is why it is dangerous to drink sea water This is also why "salting fields" was a common tactic during war, it would kill the crops in the field, thus causing food shortages.This is also why "salting fields" was a common tactic during war, it would kill the crops in the field, thus causing food shortages.

For example, Paramecium, a protist, is hypertonic when compared to the pond water in which it lives. –In spite of a cell membrane that is less permeable to water than other cells, water still continually enters the Paramecium cell. –To solve this problem, Paramecium have a specialized organelle, the contractile vacuole, that functions as a bilge pump to force water out of the cell.

As a plant cell looses water, its volume shrinks. Eventually, the plasma membrane pulls away from the wall. This plasmolysis is usually lethal.

Many polar molecules and ions that are normally impeded by the lipid bilayer of the membrane diffuse passively with the help of transport proteins that span the membrane. The passive movement of molecules down its concentration gradient via a transport protein is called facilitated diffusion. Facilitated Diffusion

Transport proteins allow facilitated diffusion

Active transport is the pumping of solutes against their gradients Some proteins can move solutes against their concentration gradient, from the side where they are less concentrated to the side where they are more concentrated. This active transport requires the cell to expend its own metabolic energy.

Endocytosis Cell takes material into cell by infolding of the cell membraneCell takes material into cell by infolding of the cell membrane Phagocytosis – eating – cell engulfs large particlesPhagocytosis – eating – cell engulfs large particles Pinocytosis – drinking – cell takes in liquidPinocytosis – drinking – cell takes in liquid animation/animation.htmwww.endocyte.com/ animation/animation.htmwww.endocyte.com/ animation/animation.htmwww.endocyte.com/ animation/animation.htm

Cell Differentiation – THE PROCESS BY WHICH CELLS CHANGE Cell Specialization – TO BECOME WELL SUITED TO PERFORM DIFFERENT FUNCTIONS.

Levels of Biological Organization OrganismOrganism Organ systemOrgan system OrganOrgan TissueTissue CellCell OrganelleOrganelle DNADNA AtomsAtoms