The Cell (pp.182- 200)

  1. Cell Discovery:
  2. History of Cell Discovery (pp. 182-183)
  3. Robert Hooke–1665- Used a microscope to examine thin slices of cork. He called the tiny boxes he saw cells. He chose the name "cells" because the chambers he saw reminded him of the small rooms in a monastery, which were called cells
  4. Anton van Leeuwenhoek- 1683- He looked at pond water through his lenses and discovered single-celled, animal-like organisms. He called these organisms “animalcules” or “wee beasties” They are now known as protozoans.
  5. Robert Brown- 1833, Observed plant cells under the microscope,observed a dark structure inside each cell and coined the term “nucleus”.
  6. Matthias Schleiden- 1838, Concluded that all plants are made up of cells.
  7. Theodore Schwann- 1839, Concluded that all animals are made up of cells.
  8. Rudolf Virchow- 1855, Studied cell reproduction and concluded that all cells come from preexisting cells.
  1. Cell Theory (pp. 182-183)

One of the fundamental ideas of modern biology and include the following 3 principles:

  1. All living organisms are composed of one or more cells
  2. Cells are the basic unit of structure and organization of all living organisms.
  3. Cells arise only from previously existing cells, with cells passing copies of their genetic material on to their daughter cells.
  1. Modern Microscope (pp.184 & 1113)

There are several types of modern microscopes

  1. Compound light microscope-Contain more than one lens and uses light rays bent throughglass to magnify objects.
  2. Electron microscope-Uses a beam of electrons. Specimen must be kept in a vacuum. Offers the advantage of much greater magnification but specimen must be non-living.
  3. scanning electron microscopeor SEM- traces the surface of the specimen and forms a 3D image
  4. transmission electron microscope or TEM- aims electron beam through specimen
  1. How to use a microscope(pp. 1113)
  • When carrying support the base and theneck
  • Place the slide on the stage and hold it in place by using the stage clips.
  • Rotate the nose piece to the low objective for viewing and scanning
  • Focus using the coarse adjustment knob
  • After focusing with the coarse adjustment knob, fine-tune it with the fine adjustment knob.
  • If you have to adjust the light turn the diaphragm
  • For higher magnification, turn the nose piece to the high power objective
  • Focus using the fine adjustment knob
  • If you can’t find what you are looking at go back to low power & focus
  1. Types of cells (pp.186)

All living things are made of cells and all cells can be divided into two groups

Venn Diagram Pro vs. Eu

  1. Cell Boundaries (187-190 & 198)
  2. Cell Wall(pp. 198)
  • The outermost boundary in plants, fungi and bacteria
  • NOT found in animal cells
  • Primary function of the cell wall is to provide structure and support
  • DO NOT regulate what enters and leaves the cell
  • Cell walls of plants are made up of cellulose
  • Cell walls of fungi are made up of chitin
  1. Cell Membrane / Plasma Membrane
  • EVERY cell is surrounded by a cell membrane (plasma membrane)
  • Made up of phospholipids
  • Selectively Permeable- only lets some things in and some things out
  • Maintains homeostasis

pp. 188- Draw & Label the cell membrane

  1. Inside a Eukaryotic Cell (pp.191-199)
  2. Cytoplasm-
  • Includes the cytosol or “cell gel” and the organelles, which means “little organs”.
  • Cytoskeleton-
  • A supporting network of long, think protein fivers that form a framework for the cell and provide an anchor for the organelles inside the cell.
  • Functions in cell movement and other cellular activities
  • Made up of:
  • Microtubules – long, hollow protein cylinders that form a rigid skeleton for the cell and assist in moving substances with in the cell
  • Microfilaments- thin protein threads that help give the cell shape and enable the entire cell or parts of the cell to move
  1. Cell Structures:(pp.192-199)

Illustration: Draw a picture of each organelle / Structure / Plant, Animal, Both, Bacteria or all 3 / Function / Write Function in your own words:
Nuclear Envelope / Phospholipid bilayer that surrounds the nucleus that has nuclear pores which allow RNA to leave the nucleus.
Nucleus / Control center of the cell. Genetic information is found as chromatin, which is DNA wrapped in protein
Nucleolus / Small, sense region in the nucleus. Site of ribosome production
Ribosomes / Tiny, granulated organelles located on the Endoplasmic reticulum or found in the cytosol. Site of protein production. Made up of two components- RNA and protein- and are not bound by a membrane.
All cells (pro & eu) have ribosomes
Rough Endoplasmic Reticulum
(ER) / Continuation of the nuclear envelope. Called “rough” because it has ribosomes attached. Functions to modify and transport proteins. Most of these proteins are packaged into vesicles (like bubbles or sacs) and shuttled to the Golgi apparatus
Smooth Endoplasmic Reticulum
(ER) / Similar to rough ER in structure, except it does NOT have ribosomes. Manufactures lipids, breaks down glycogen, detoxifies poisons, and stores calcium.
Golgi Apparatus / Flattened, round sacs that look like a stack of pancakes. Receives, modifies and ships products by way of vesicles into the cytosol then to the cell membrane
Vacuole / Sacs that may be used as storage for water, proteins, carbohydrates, salts or wastes. Plants have a large central vacuole.
Lysosome / Vesicles that contain enzymes that digest excess or worn-out organelles and food particles. They also digest bacteria and viruses that have entered the cell.
Centrioles / Made up of groups of microtubules that function during cell division.
Mitochondria / The “Powerhouse” of the cell. Cell generators that convert fuel particles (glucose) into useable energy (ATP).
This process is known as Cellular Respiration.
C6H12O6 + O2 CO2 + H2O + ATP
Chloroplast / Capture light energy and convert it to chemical energy through a process called photosynthesis.
CO2 + H2O + Light  C6H12O6 + H2O
Cilia & Flagella / Some cells have these. Project outside the plasma membrane. Cilia are short, numerous projections that look like hairs. Flagella are longer and less numerous. These projections move with a whiplike motion

Venn Diagram of the Cell Organelles:

Label & Color the following Cells:

(pp. 192)

Cell Wall – Light Green

Cell Membrane- Black

Cytoplasm- Leave white

Chloroplasts- Dark Green

Mitochondria- Red

Golgi Apparatus- Light Blue

Microtubules- Dark Brown

Nuclear Membrane- Dark purple

Nucleolus- tan

Nucleoplasm- gray

Ribosomes- orange

Rough ER- Dark Blue

Smooth ER- Pink

Vacuole- Yellow

Lysosome- Light Green

Centrioles- Light Purple

  1. Viruses: (pp.525-531)
  • One theory of their origin is that viruses came from parts of cells. Scientists have found that the genetic material of viruses is similar to cellular genes. These genes somehow developed the ability to exist outside of the cell
  1. Discovery
  2. In Russia, Dmitri Ivanovsky was asked to investigate a disease affecting tobacco plants
  3. He found juice from one plant infected other plants, even when passed through fine filters
  4. He found no cells in this “juice” and concluded that the disease was caused by a “poison”
  5. Later it was suggested that the infecting agent was a very tiny particle
  6. One scientists isolated virus crystals inferring that these virus particles were not living
  1. What is it?
  2. Nonliving stand of genetic material with a protein coat
  3. Not considered alive because it does not exhibit all characteristics of life
  4. Not made up of cells
  5. Cannot reproduce on their own
  6. Does not take in or use energy
  7. Some of the smallest disease-causing structures that are known.
  8. About 10,000 cold viruses can fit in the period of this sentence.
  1. How is a Virus Classified?
  2. Type of nucleic Acid- DNA or RNA
  3. Shape of Protein Coat(called a Capsid)
  4. Retrovirus
  5. Class of RNA viruses that changes its RNA into DNA when injected into a host cell
  6. Contains reverse transcriptase enzymes
  1. How do they infect?
  2. Viruses us a host cell to reproduce. The virus must inject their genetic material into a host cell, so it can instruct the host cell to make new virus particles
  3. Viruses are specific to the type of cell it can infect
  4. A Virus is specific in the type of cell it invades because it attaches to specific binding sites called Receptors on the host cell
  1. Hijacking a Host Cell to Reproduce:
  2. The virus attaches to a receptor on the host cell
  3. Genetic info is inserted into the host cell
  4. Host Cell is forced to make virus genetic material (DNA or RNA) and proteins (capsid)
  5. Viruses are assembled (put together)
  6. New virus particles break out of the host cell killing it

*(Some viruses bud out without destroying the host cell. -ex. HIV

Lytic Cycle:Viral reproduction occurs immediately and host cell death in most cases

Lysogenic Cycle:

•Viral DNA hides out by inserting itself into the host DNA.

•Prophage (or Provirus): viral DNA that has been inserted into the host’s DNA.

•It may lay dormant (inactive) for a period of time or it may periodically release a few viruses (switches to lytic cycle).