Bacteria

11SCI - Microbes

Finn Le Sueur

2024

Bacteria Brainstorm

Structure of a Bacterium

  • Glue the diagram into the centre of a page
  • We will make notes around the outside

Movement

  • Most movement is achieved using the flagellum for swimming
  • Some movement can be achieved using pili (twitching)

Respiration

  • Bacteria do aerobic respiration which requires oxygen
  • Occurs in the plasma membrane of the bacteria
  • \(C_{6}H_{12}O_{6} + O_{2} \rightarrow CO_{2} + H_{2}O + energy\)
  • There have been some bacteria that do anaerobic respiration (without oxygen) but this is less common

Sensitivity

  • As we will show tomorrow, bacteria are sensitive to their environment
  • They can be killed by altering environmental factors such as: oxygen availability, temperature, water availability, food availability, and chemicals that break down their cellular structure

Growth

  • Growth is a way to produce the materials required for reproduction
  • For example, bacteria make proteins in small organelles called ribosomes which can be found near the nucleus
  • Proteins are used for everything from respiration to building the plasma membrane and everything in between

Reproduction

  • Like fungi, bacteria reproduce through binary fission
  • In this process the bacteria makes a clone of itself
  • Some bacteria undergo a process of conjugation where they swap some genetic material with another through direct physical contact
  • Some other bacteria simply scoop up miscellaneous DNA floating around the environment

Excretion

  • The processes of excretion is called exocytosis
  • Byproducts of cellular life processes are captured in vesicles
  • These vesicles fuse with the plasma membrane before releasing their contents to the outside of the cell
  • Sketch a quick diagram of this process

Nutrition

  • Nutrients are brought into the cell via a process called endocytosis
  • The nutrients are captured into vesicles and transported around the cell to the required area
  • Sketch a quick diagram of this process

Ngohe / Task

  • Use your device to research the purpose of the cellular structures that we did not discuss
    • Cytoplasm
    • Cell wall
    • Cell capsule
    • Nucleoid
    • Plasmids