All About Cells

1. All About Cells Name: _____________ Period: ____________

2. The Cell Theory States: • All living things are composed of cells 2. Cells are the basic units of structure and function in living things 3. New cells are produced from existing cells Now how did we get to this- Lets look at history

3. History Anton van Leeuwenhoek • The first lenses were used in Europe in the late 1500s by merchants who needed to determine the quality of cloth. They used their magnifying lenses to examine the quality of the thread and the precision of the weave in a bolt of cloth. From these simple glass lenses, combinations of lenses were put together. • In Holland in the early 1600s, two useful instruments were constructed: the telescope and the microscope. • Dutch businessman Anton van Leeuwenhoek (lay-vuhn-hook) became one of the first people to use a microscope to study nature. Using only a single powerful lens, van Leeuwenhoek crafted instruments that could produce magnified images of very small objects. His simple microscope enabled him to see things that no one had ever seen before. He was the first person, for example, to see tiny living organisms in a drop of water. In 1674 Van Leeuwenhoek carefully observed the living things in pond water and made detailed drawings of each kind of organism. He called these organisms animalcules. • In 1665, English physicist Robert Hooke used one of the first light microscopes to look at thin slices of plant tissues. One of these, a slice of cork, especially caught his eye. Under the microscope, cork seemed to be made of thousands of tiny chambers. Hooke called these chambers “cells,” because they reminded him of a monastery’s tiny rooms, which were also known as cells. The term cell is used to this day. Hooke’s discovery stimulated other scientists to search for cells in other living things. • Before long, it became apparent that cells were the basic units of all forms of life. • In 1838, German botanist Matthias Schleiden (shly-dun) concluded that all plants are made of cells. • In 1839, another German scientist, Theodor Schwann, concluded that animals are also made of cells. • Rudolf Virchow (fur-koh), a German physician, studied cell reproduction. In 1855, he summarized years of research by stating, “Where a cell exists, there must have been a preexisting cell.…” or cells come from cells Robert Hooke Matthias Schleiden Theodor Schwann Rudolf Virchow

4. People of the Cell Theory Draw this person Draw this person Draw this person Use the history page to fill this out This person did what? This person did what? This person did what? Anton van Leeuwenhoek Robert Hooke Matthias Schleiden Draw this person Draw this person This person did what? This person did what? Theodor Schwann Rudolf Virchow

5. 1500 In the 1500’s- 1600 In the 1600’s- In 1665- In 1674- 1700 1800 In 1838- In 1839- In 1855- Timeline: Who did what? Use the history page to fill this out

6. Intro Questions • 1. The transport of material from high to low concentration is _passive diffusion_ • 2. The transport of materials from low to high concentration is _active transport_ • 3. A cell has 5% NaCl inside and it is in a solution that is 10% NaCl. In order to maintain its 5% NaCl concentration is uses __carrier_ proteins and does __active__ transport. • 4. A cell has 2% NaCl inside and it is in a solution that is 5% NaCl. In order to get to a 5% concentration of NaCl is uses __channel_ proteins and does ___passive__ transport. • 5. Which way does water flow in a hypertonic solution- out of the cell • 6. Which way does water flow in a hypotonic solution- in to the cell

7. Compound light microscope Ocular or Eyepiece 10x magnification Observation tube Nosepiece Arm Low power objective lens (4x) Medium power objective lens (10x) Stage High power objective lens (100x) Course Adjustment Knob Stage Clips Iris diaphragm Fine Adjustment Knob Light Source Base Total magnification = magnification of eyepiece x objective lens Compound light microscope- A combination of two lenses magnify an object. Light must pass through the specimen to view. Electron Microscope- focus beams of electrons on specimens to form images more than 1000 times smaller than a compound light microscope.

8. Basic Cell Structure • Cell Membrane- is a thin, flexible barrier around the cell • Nucleus- a large structure that contains the cell’s genetic material and controls the cell’s activities • Cytoplasm- material inside the cell membrane—but not including the nucleus\ • The semifluid substance that fills the cytoplasm is called the cytosol Label these three parts below Cell membrane Cytoplasm Nucleus

9. The Cell Membrane Phospholipid bilayer- The cell membrane is a double layer of phosphates with fatty acids Fluid mosaic model- Cell membrane and embedded proteins are not locked into position, they flow around.

10. Prokaryote vs. Eukaryote • Prokaryote - have cell membranes and cytoplasm but do not contain nuclei. • All bacteria are prokaryotes. • Eukaryote- Contain nuclei. Also have a cell membrane, cytoplasm, and most have organelles. • All plants, animals, and fungi, and many microorganisms, are eukaryotes. • Eukaryote cells are much larger than prokaryote cells • Organelles- specialized structure that performs important cellular functions within a eukaryotic cell Fill in this Venn Diagram using the pictures of prokaryotes and eukaryotes Prokaryote Eukaryote

11. Review • What three statements describe the cell theory? • What is the main characteristic that distinguishes eukaryotes from prokaryotes? 3. Name two structures that all cells have. Look throughout this guide to find answers

12. Cell Structures • Cell Wall- Cell walls are found in many organisms, including plants, algae, fungi, and nearly all prokaryotes. • Animal cells do not contain cell walls. Cytoskeleton • Cytoskeleton- a network of protein filaments that helps the cell to maintain its shape. (also involved in cell movement) • Parts of the cytoskeleton: • Microtubule- hollow tube of protein that maintains cell shape and can also serve as a “track” along which organelles are moved • Microfilaments- long, thin fiber that functions in the movement and support of the cell

13. Cell Structures • Nucleus- large structure inside some cells that contains the cell’s genetic material (DNA) and controls the cell’s activities • Nuclear Envelope- double-membrane layer that surrounds the nucleus of a cell • Chromatin- Granular material visible within the nucleus. Consists of DNA bound to proteins. • Chromosomes- X like structure formed when chromatin condenses • Nucleolus- small, dense region within most nuclei in which the assembly of ribosomes begins

14. Organelles • Ribosome- small particle in the cell on which proteins are assembled; made of RNA and protein • Endoplasmic Reticulum (ER)- internal membrane system in cells in which components of the cell membrane are assembled and some proteins are modified • Rough ER- The part of the endoplasmic reticulum that is involved in the synthesis of proteins. Named because ribosomes that stud its surface • Smooth ER - Does not have ribosomes on its surface. contains collections of enzymes that perform specialized tasks, such as the synthesis of lipids. Endoplasmic Reticulum

15. Organelles • Golgi Apparatus- stack of membranes in the cell in which enzymes attach carbohydrates and lipids to proteins • Lysosomes- cell organelle filled with enzymes needed to digest certain materials in the cell

16. Organelles • Centrioles- tiny structures located in the cytoplasm of animal cells near the nuclear envelope. These play a role in cell division. • Vacuole- cell organelle that stores materials such as water, salts, proteins, and carbohydrates

17. Organelles Inside a chloroplast • Chloroplast- organelle found in cells of plants and some other organisms used for photosynthesis. Use energy from sunlight to make energy-rich food molecules (glucose) by photosynthesis. Contains chlorophyll Photosynthsis Carbon Dioxide + Water Glucose + Oxygen 6 CO2 + 6 H2O  C6H12O6 + 6 O2

18. Organelles • Mitochondria- cell organelle that releases energy from stored food molecules. • Involved in cellular respiration- turning carbohydrates into energy. • Cells that need more energy have more mitochondria

19. Other structures • Cilia (cilium): short hairlike projection; produces movement in many cells • Flagella (flagellum): whiplike structure on some cells that is used for movement Cilia Flagella

20. Mitochondria and Chloroplasts contain their own DNA genetic information separate from the cells DNA. • Lynn Margulis suggests that this is because they are descendants of ancient prokaryotes. • Endosymbiotic theory • The first eukaryotes may have formed from one bacteria engulfing another without killing it. • Later a symbiotic relationship was formed

21. Plant Cells Cell wall Chloroplasts Large central vacuole No centrioles Animal Cells Have centrioles No cell wall No chloroplasts No large central vacuole Plant vs Animal Cells Both are eukaryotic cells- Both have nucleuses, organelles, cell membranes, cytoplasm Plant and animal cell differences

24. Diversity of Life • Unicellular organisms- A single-celled organism • Unicellular organisms include both prokaryotes and eukaryotes. Contractile Vacuole A eukaryotic unicellular organism (paramecium) A prokaryotic unicellular organism Contractile vacuole- pumps fluid from within the cell to the outside by alternately filling and then contracting • Multicellular organisms- organisms that have more than one cell working together. Have cell specialization • Cell specialization- specific roles for different types of cells

25. Levels of organization • Cells- the basic unit of life • Tissues- a group of similar cells that perform a particular function • Organs- many groups of tissues work together • Organ Systems- A group of organs that work together to perform a specific function • Organism- An entire living being mad up of organ systems