DO NOW …  What characteristics are common to all living things?  What are cells?  Name different types of cells you know of...  What is a difference between living and non- living things?

 THE CELL Chapter 1

DO NOW …  What are the two main types of cells?  Do all cells have the same structure? Look at the cells to the right. What are some similarities? Differences?

Objectives  Describe how cells were discovered and named.  Identify the scientists that discovered and observed cells.  List the 3 parts of the cell theory.

What is a cell?  Basic structural and functional unit of all living organisms!  They come in different shapes + sizes

Unicellular vs. Multicellular  Unicellular – a single cell  Multicellular – made up of many cells

Who discovered the cell? ROBERT HOOKE  Observed dead cork cells  Said boxes looked like tiny rooms or jail “cells”.  Used a microscope at 30x magnification

How were cells discovered? The light microscope helped discover cells!

 Cork cells! *Cork is from tree bark (dead cells) Animalcules 

Who else discovered the cell? ANTON VAN LEEUWENHOEK  Observed pond water  1 st to observe “living” cells  Used a microscope at 300x magnification

Do you have these recipes at home? People thought organisms grew from non-living materials!

Fransisco Redi Experiment  Placed meat in both an open container and a closed container to see what happened.

Redi’s Conclusion  Maggots come from flies, NOT the meat!  Life must come from life, which proved that spontaneous generation is not real!  People still did not believe him but he was right.

Louis Pasteur Experiment  Showed that bacteria are present in air and do not appear spontaneously.

Louis Pasteur Conclusions  Discovered that cells MUST come from other cells  Disproved “Spontaneous Generation” and said life cannot just appear out of no where.  Helped verify Redi’s research!

Pasteurization  Pasteur came up with the idea of Pasteurization after discovering bacteria could contaminate milk from the air.  This process kills the bacteria so that it does not harm us!  Used in milk, cheese, yogurt, etc.  content/chp03/ html content/chp03/ html

 Cell Theory =  Every living thing is made of one or more cells  Cells carry out the functions needed to support life  Cells come only from other living cells

Do Now  Please complete the worksheet in front of you!!

Objectives  Compare and contrast a scanning electron microscope vs. a transmission electron microscope.  Describe prokaryotic and eukaryotic cells.

Bill Nye!! 

Section Microscopes How small are cells?  Unit used = micrometer (um) One millionth of a meter  Most cells range from 1 um to 1000 um.

Types of Microscopes 1. Light Microscope 2. SEM Microscope 3. TEM Microscope

Light Microscope  Uses light  Looks at thin specimen  Total Magnification = 40x-1000x  Use to see cells, but not detailed organelles

SEM vs. TEM SEM 1. “Scanning electron microscope” 2. Beams of electrons bounce off the surface of the coated cell. 3. Images appear 3D- Outside Specimen 4. Total Magnification = 100,000x 5. Must be dead . Specimen coated in metal TEM 1. “Transmission electron microscope” 2. Electrons pass through the think section. 3. Images appear 2D 4. Total Magnification = 300,000x 5. Allows us to see organelles inside the cell

Do Now!!  What are the three types of microscopes?  What is found INSIDE a cell?  Do plant cells and animal cells have the same stuff inside?

Objectives  To compare and contrast animal vs. plant cells.  Identify each organelle in a diagram of a cell.  Explain the function of each organelle  To create flash cards for the next test

SEM

TEM

Prokaryotic vs. Eukaryotic cells What are the differences you can see?

Prokaryotic Cells  Have circular DNA  NO nucleus  Does not have membrane bound organelles  Most unicellular organisms are prokaryotes Example: Bacteria

Eukaryotic Cells  Have linear DNA – double helix shape  Has nucleus  Have membrane bound organelles  All multicellular organisms are eukaryotic cells. Some are unicellular though. Example: You!

Cell Organelles 1. Plasma membrane 2. Cytoplasm/cytoskeleton 3. Nucleus 4. Ribosomes 5. Endoplasmic Reticulum 6. Golgi Apparatus 7. Lysosomes 8. Centrioles 9. Cilia and Flagella 10. Mitochondria 11. Central Vacuole 12. Chloroplasts 13. Cell Wall Each organelle has its own purpose and function!!

THE OUTSIDE – protects the internal structures of the cell. Selective permeability - Determines what comes in and out of the cell A.K.A- Cell Membrane! Found in: Animal and Plant cells Plasma Membrane

Cytoplasm/Cytoskeleton Cytoplasm- Clear FLUID that contains the organelles. Cytoskeleton- Provides the FRAMEWORK for the cell, holds organelles in place. Found in: Plant and Animal cells

Nucleus Nucleus- CONTROLS the cell Nucleolus- produces ribosomes Nuclear Pores- Allows things in and out of the nucleus. Nuclear Envelope- Membrane surrounding nucleus Found in: Plant and Animal

Challenge Question  Where do you find the DNA in a eukaryotic cell?  If prokaryotes do not have a nucleus, where is their DNA?

Ribosomes Produces Proteins! Proteins are made up of one or more polypeptide chains of amino acids. Found in: Plant and Animal

Endoplasmic Reticulum Rough- Contains ribosomes and synthesizes PROTEINS Smooth- No Ribosomes, synthesizes LIPIDS (fats) Found in: Plant and Animal

Index Cards! Front : Name of Organelle Drawing Back : Location Function

Do Now!!  Please finish making your 5 notecards from last class!

Objectives  To compare and contrast animal vs. plant cells.  Identify each organelle in a diagram of a cell.  Explain the function of each organelle  To create flash cards for the next test  To observe different kinds of cells under a microscope

Golgi Apparatus Modifies proteins and fats and gets them ready for export! (proteins are eventually released to outside of cell) Found in: Animal and Plant

Lysosomes Contains ENZYMES that break down cellular waste product and debris Found in: Animal (rare in plant) *The clean-up crew!

Centrioles Organelles made of microtubules involved in cell division (located in cytoplasm)! (will talk about this later when we do mitosis!) Found in: Animal

Cilia and Flagella Flagella- Used in cells for movement (longer & less numerous than cilia). Cilia- Used in stationary cells for moving substances around the outside of the cell (look like hairs). Found in: Animal and Prokaryote

Mitochondria Convert oxygen into ENERGY (ATP) (we will talk about this more when we do cellular respiration!!) Found in: Animal and Plant *Powerhouse of the cell!!

Index Cards! Front : Name of Organelle Drawing Back : Location Function

Do Now!! Which is a plant cell? Animal cell? How do you know? What is the role of the mitochondria?

Objectives  To compare and contrast animal vs. plant cells.  Identify each organelle in a diagram of a cell.  Explain the function of each organelle  To create flash cards for the next test  To label animal and plant cells

Central Vacuole LARGE WATER “bubble” in the plant cell Maintains the SHAPE of the cell, without it, the plant cell would shrink and the plant would wilt Stores water, along with ions, nutrients, and waste. Found in: Plant

Chloroplasts Captures LIGHT ENERGY and converts it to chemical energy (sugar) Found in: Plant

Cell Wall Supports the plant cell and maintains its shape Works with central vacuole to maintain “Turgor Pressure” Found in: Plant

Index Cards! Front : Name of Organelle Drawing Back : Location Function

Challenge Question!  How can the chloroplast, a structure found in plant cells but not in animal cells, provide energy for both plants and animals ?

Do Now!!  Please create a Venn diagram: PlantAnimal

Objectives  Identify each organelle in a diagram of a cell.  To label animal and plant cells.  To complete reading activity summing up organelles and their functions.

Endosymbiotic Theory Explains the origin of chloroplasts and mitochondria and their complex, double membranes. Theory: Chloroplasts and Mitochondria were once prokaryotes that were engulfed!!

Theory = Evidence!! Have circular DNA like bacteria Replicates(reproduces) like bacteria separate from the host cell Make their own proteins Two membranes (one from the host cell and one from their own cell membrane)

Specialization Specific cells perform specific functions. Ex: Blood cells can only be blood cells. Muscle cells cannot be turned into blood cells.

Organization Organisms are organized: Cells Tissue Organ Organ System Organism

Organization: plants too! Cell  Tissue  Organ (leaf)  Organ system (leaves, stems, roots)  Organism