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What Is the Main Difference Between a Prokaryotic and Eukaryotic Cell?

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What Is the Main Difference Between a Prokaryotic and Eukaryotic Cell? What is the main difference between a prokaryotic and eukaryotic cell? Key Question: How do prokaryotes and eukaryotes compare? Sunday, 7 June 2020 Prokaryotes and Eukaryotes Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? Task 1 • Use the internet to find and draw a diagram of a bacteria cell and label the following: • Nucleiod • Cytoplasm • Cell membrane • Slime capsule • Cell wall • Ribosomes • Plasmids • Flagellum • Annotate their functions. Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? Task 2 • What is a prokaryote cell and what is a eukaryote cell? • Which cells are examples of which? • In what organisms would you find them • What are the differences in their organelles? • Create a table and tick off the organelles present in each type of cell • CHALLENGE: Plant and bacteria cells both contain cell walls but are they are same thing? Find out about the basic structure/composition of each one. Key Question: How do prokaryotes and eukaryotes compare? Types of bacteria The last slide of the PowerPoint provides a sheet that will help you summarise this lesson OR you can make your own notes using that to help you structure them. Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? 1mm = 1000 μm 100 μm 20 eukaryotic cells 1000 nm 10 μm 200 cells 7.5 μm Prokaryotic cell because 7.5 μm is close to 5μm, which the average size. 0.3 cm = 300 μm = 300,000 nm Key Question: How do prokaryotes and eukaryotes compare? Task 1 Key Question: How do prokaryotes and eukaryotes compare? Gram Staining Gram staining is a technique used to identify different types of bacteria under the microscope. Bacteria are grouped into two types depending on how they react to the process: • Gram positive • Gram negative Key Question: How do prokaryotes and eukaryotes compare? Task 2 Gram staining is useful because it can help scientists to identify those bacteria that cause infections. You are going to watch a video on Gram staining; make notes on the process to help you complete Task 3 of the summary sheet on the steps involved in the process. Key Question: How do prokaryotes and eukaryotes compare? Gram Staining Was invented in 1884 by Dutch Physician, Hans Christian Gram. Key Question: How do prokaryotes and eukaryotes compare? Gram Staining Procedure Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? So how do they look under the light microscope? Look at the following pictures and then complete Task 3 on the summary sheet. Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? Key Question: How do prokaryotes and eukaryotes compare? Gram Positive Bacteria Key Question: How do prokaryotes and eukaryotes compare? Gram Positive Bacteria Key Question: How do prokaryotes and eukaryotes compare? Gram Negative Bacteria Key Question: How do prokaryotes and eukaryotes compare? Gram Negative Bacteria Key Question: How do prokaryotes and eukaryotes compare? Mixture of types Key Question: How do prokaryotes and eukaryotes compare? Can you tell which is Gram Negative? Positive? Key Question: How do prokaryotes and eukaryotes compare? Task 4 What is the difference between a gram-positive and a gram-negative bacteria? Describe the differences for Task 4 on the summary sheet Key Question: How do prokaryotes and eukaryotes compare? What is the difference between a gram positive and a gram negative bacteria? In Gram-negative bacteria there is a much thinner peptidoglycan layer and an extra, outer membrane that forms the cell wall along with the inner cell membrane. Gram- positive bacteria only have a thick peptidoglycan layer and no outer membrane. Key Question: How do prokaryotes and eukaryotes compare? Gram Positive/Negative Cell Walls Gram-negative bacteria contain much les peptidoglycan but more lipids (fats) in their cell walls. These differences in cell wall structure means that they respond differently to antibiotics. For example, penicillin stops cell wall production on growing Gram-positive bacteria but doesn’t have the same effect on Gram- negative. Key Question: How do prokaryotes and eukaryotes compare? Task 5 Use the internet to find information to answer section 5 on the summary sheet. Use the internet to research the following questions: 1) Why do bacteria produce toxins? 2) How are toxins produced by the cell? Put the sentences on the next slide in order to describe this process. Key Question: How do prokaryotes and eukaryotes compare? Statement Order A section of DNA containing the genetic code for the toxin unwinds. The 70S ribosomes translate the messenger RNA into a toxin. Bacterial cells produce toxins that have an effect on other organisms. RNA nucleotides line up on the unwound DNA, this is called complementary base pairing. Messenger RNA is formed. This process is called transcription. The toxin is moved to the surface of the bacteria cell. DNA is free in the nucleoid section of the cell. The messenger RNA travels to the 70S ribosomes. Key Question: How do prokaryotes and eukaryotes compare? Statement Order A section of DNA containing the genetic code for the toxin unwinds. 3 The 70S ribosomes translate the messenger RNA into a toxin. 6 Bacterial cells produce toxins that have an effect on other organisms. 1 RNA nucleotides line up on the unwound DNA, this is called complementary base pairing. Messenger RNA is formed. This process is 4 called transcription. The toxin is moved to the surface of the bacteria cell. 7 DNA is free in the nucleoid section of the cell. 2 The messenger RNA travels to the 70S ribosomes. 5 Key Question: How do prokaryotes and eukaryotes compare? 1. Diagram – Complete the labels 3. What are the differences between gram positive and gram negative bacteria? 5. Research 1.) Does penicillin work against Gram positive or Gram negative 2. What are the steps of the Gram stain bacteria? Step 1: Step 2: 2) How does Penicillin work against this type of bacteria? Step 3: 3) Why does penicillin not work against the other type of bacteria? Step 4: 4) Find examples of Gram positive and negative bacteria and what 4. What colour is: diseases they cause. i) Gram negative bacteria? Keyii) QuestionGram Positive: How bacteria do prokaryotes and eukaryotes compare?.
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