2Where We’re Going…There are 2 benchmarks associated with cells at the middle school level.They are…
3BenchmarksSCI.III.1.MS.1- Demonstrate evidence that all parts of living things are made of cells.SCI.III.1.MS.2- Explain why and how selected specialized cells are needed by plants and animals.
4Important Concepts From SCI.III.1.MS.1 Types of living things…(each of the 5 kingdoms)MoneransProtistsFungiPlantsAnimalsParts of organisms…(fungi, plants, animals)Cells->Tissues->Organs->Organ Systems->OrganismsCommon plant/animal cells…Onion skin cells (plant cells)Cheek cells (animal cells)Single Celled Organisms…(Protists)ParameciumAmoebaEuglenaTools…MicroscopeMagnifying glass/hand lens
6Cells…Cells are the smallest units that carry out the activities of life in organisms.Some are complete organisms , such as unicellular bacteria and protozoa. (Kingdom Monera and Protista)Others are specialized components of multicellular organisms. (Kingdom Fungi, Animalia, and Plantae)
7Size of Cells…Some cells, like bacteria are incredibly small, (.2 micrometer)Other cells, like the nerve cells that run down a giraffe’s leg can be up to 2 meters long.
8Cells…Members of Kingdom Monera are too small to be seen with our classroom microscopes, but we will take a peek at some members of Kingdom Protista in the not too distant future. Both of these Kingdoms contain only unicellular members.Kingdom Plantae, Kingdom Fungi, and Kingdom Animalia have specialized cells that are part of a larger organism.
9Cell Types Cells can be either Prokaryotic-no membrane around nuclear material. “Naked DNA” (bacteria-Kingdom Monera only)Eukaryotic –have a nucleus with a membrane around it. (all others-Kingdom Protista, Fungi, Plantae & Animalia)All Eukaryotic cells have similar internal structures.Like You!...Get it….Eukaryotic…Like “Eu”….
10Inside Cells…We will look at cells in the near future, but in order to understand completely, first you should know a few things like…how to look inside a cell, (microscopes),how cells work (cell theory)what to look for inside a cell (organelles).
11Microscopes A simple microscope has one lens. By combining 2 lenses, you can get an image that is larger than the image produced with only one lens.We use compound light microscopes that have two lenses. They let light pass through the specimen and lenses to enlarge the image and bend light toward your eye.
12Early MicroscopesEarly microscopes did not produce clear images, so the discovery of the cell had to wait for microscope technology to improve before that could happen.Think about it. Glass was not even widely available or used in homes until the 1600’s. It’s difficult to make lenses without glass.
13MicroscopesBefore we can look at microscopic things we need to be familiar with microscopes.Please see the diagram and function of the parts of the microscope that your teacher has given.Be prepared for a test on Thursday, June 1st. You MUST PASS THE TEST BEFORE you can USE a microscope.
14Microscope HistoryHans and Zacharias Janssen were father and son lens grinders.They produced the first compound microscope (2 lenses).
15Microscope HistoryIn 1665, Robert Hooke looked at cork through a microscope, and observed hollow roomlike structures.He called them “cells” because they reminded him of the rooms that monks lived in.
16Microscope HistoryA few years later, Anton van Leeuwenhoek, a Dutch fabric merchant and amateur scientist, looked at blood, rainwater & scrapings from teeth.He noted that some seemed to move, and realized that he was looking at living things.
17Microscope HistoryEventually the observations and discoveries of many scientists led to Cell Theory.Today we continue to learn new things and build upon this body of knowledge.
18Cell Theory Cell theory states that… 1. All organisms are made up of one or more cells.2. Cells are the basic units of structure and function in all organisms.3. All cells have evolved from other cells.
19What’s Inside a Cell?Organelles are very similar to human organs in that they help perform specific functions. The organelles just have stranger names.So that you’re not too confused as we continue, here’s a glimpse at the big picture.Link to organelle diagram.Another Link to organelle diagram.Interactive Cell DiagramSeveral handouts of cells. Pass out. Use overhead transparencies as well.
20Cell Organelle Overview Video Clips… Types of CellsThe Living Cell: Structure and FunctionIntroduction to the Cell
21Inside Cells…You will need to know the functions of the following cellular organelles…vacuoleNucleusCell membraneCell wallCytoplasmMitochondriaGolgi bodiesLysosomesChloroplastsChlorophyllEndoplasmic Reticulum
22Organelles…A cell membrane is a structure that forms the outer boundary of the animal cell and allows only certain materials to move into (food & oxygen) and out of (wastes) cells.It can be thought of as a “bag” that holds the rest of the stuff inside the cell.Link to cell membrane photo
23Organelles…Cytoplasm is the gel-like material inside the cell. (Like jello or a raw egg white)It is a mixture of proteins, fats, carbohydrates (sugars), salts, water and other substances.The structures within the cytoplasm of cells are organelles .cytoplasm moves around within the cell, organelles can come into contact with one another, allowing certain processes to occur. This movement of the cytoplasm is called cyclosis.
24Organelles… Each organelle has a responsibility or function. Mitochondria break down food for energy.They can be thought of as the “powerhouse of the cell.”Link to mitochondria photoLink to another mitochondria photoLink to mitochondria diagram
25Organelles Vacuoles store food, water, waste materials. They can be thought of as the “Stomach of the cell”.Video of vacuole contracting
26OrganellesEndoplasmic Reticulum is involved in the movement of material.It can be thought of as the “highway of the cell”.Link to photo of ERLink to diagram of ER
27OrganellesThe rough endoplasmic reticulum contains on it smaller organelles called ribosomes.Ribosomes make proteins.They are part of the “manufacturing centers” of the cell.Look back at the ER images to see if you can see the ribosomes.
28Organelles Golgi Bodies are also associated with the ER. Golgi bodies act as a transport, packaging materials into vesicles and sending them off either to other organelles or for removal.They can be thought of as the “post office” of the cell.Link to photo & diagram of golgi bodies
29OrganellesLysosomes contain powerful digestive enzymes that are used to destroy invading matter and unwanted cellular material.They can be thought of as the “garbage trucks” or “recycling centers” of the cell.Link to lysosome picture.
30Organelles Nucleus is the largest organelle in the eukaryotic cell. It directs all of the activities of the cell, and can therefore be thought of as the “brain of the cell.”It also contains the chromosomes, which carry the code for the inherited characteristics of the cell.Link to nucleus/chromosome photo
31OrganellesCell walls are only part of plant cells. They function in providing structure; a skeleton of sorts for the plant.Link to cell wall picture.
32OrganellesPlant cells are also unique in that they contain chloroplasts which convert light energy into food.Chloroplasts are generally green because they contain the green pigment chlorophyll.Link to chloroplasts/chlorophyll picture.
33Animal Cells – Human Cheek Cell We will be looking at some animal cells. You’re an animal and you have cells all over. We will take a look at cells from the inside of your cheek.Look at some photos of human cheek cells here…
34Plant Cells- Onion Cell We will be looking through the microscope at some plant cells. Onion cells are a typical plant root cell.Click here to see some photos.
35Plant Cell- Elodea Leaf Cell The elodea leaves that we will look at represent typical plant leaf cells.Look at some photos of them here…
36Kingdom Protista- Unicellular Organisms We will look at a few Protists.Protists are classified according to how they move. They use the following…PseudopodiaFlagellumCiliaYou will see examples on the next few pages.Make jello cell models.Create and take test.
37Amoeba Amoeba are one member of Kingdom Protista. Protists are classified according to how they move.Amoeba move by using pseudopodia or streaming cytoplasm.They are predators and hunt for and devour microscopic prey.This is what an amoeba looks like.Label me (ditto)Label me (answers)
38Euglena Euglena is another member of Kingdom Protista. Euglena move by rotating a long whip-like appendage called a flagella.VideoPhotoDiagram
39Paramecium Paramecium are another type of Protist. Paramecium move by waving their short cilia like little oars.VideoPhotoDiagram
40Cells -> Tissues ->Organs -> Systems ->Organisms According to one of the benchmarks that were presented at the beginning of this section, we will o look at some specialized eukaryotic cells.Specifically…Red blood cellsWhite blood cellsMuscle cellsBone cellsNerve cellsEgg/sperm cells
41Red Blood CellsThe function of red blood cells is to nourish other cells by carrying food and oxygen to them, and to cleanse other cells by carrying away wastes.They are part of your circulatory system as well as your immune system.Red blood cells look like this…PhotographDiagram
42White Blood Cells / Leukocytes The function of white blood cells (Leukocytes) is to protect the other cells by battling anything that threatens them.They are part of your circulatory system, and part of your immune system.Here are what white blood cells look like.PhotographDiagram
43Muscle CellsThe function of muscle cells is to expand and contract. This may either move the body (with the help of the skeleton), or transport fluids (blood) throughout the rest of the body.They are part of your musculoskeletal system.Check out what muscle cells look like.Muscle cell photo/diagram siteVideo
44Bone CellsThe function of bone cells is to provide structure for bones. Bones then provide structure for the rest of the body.They are part of the musculoskeletal system.This is what bone cells look like.Photodiagram
45Nerve CellsThe function of nerve cells is to provide a route for electrical stimulation throughout the body.They are part of your nervous system.This is what nerve cells look likePhotoDiagramLabel Me (Ditto)Label Me Answers
46Egg CellsThe function of egg cells is reproduction. This promotes survival of the species.They are part of the reproductive system.They look like this…EggPhotoDiagramLabel Me (ditto) / Label Me (answers)
47Are We Done??? I think that covers everything. Be ready for an Organelle Quiz on Friday, June 9th…..be sure to add it to your agenda.Let’s go back to the beginning of this power point and review.