bio paper 1

• Eukaryotes

  Organisms with cells containing a nucleus and organelles.
• Prokaryotes

  Organisms with cells lacking a nucleus and membrane-bound organelles.
• Organelles

  Structures within a cell that perform specific functions.
• Orders of Magnitude

  Scale used to compare sizes, e.g., 10 times bigger is 10^1.
• Prefixes

  Terms like centi, milli, micro, and nano indicating multiples of units.
• Nucleus

  Cell organelle containing DNA and surrounded by a nuclear membrane.
• Cytoplasm

  Gel-like substance inside cells where chemical reactions occur.
• Cell Membrane

  Outer boundary of a cell that controls what enters and exits.
• Mitochondria

  Organelles where aerobic respiration and energy production occur.
• Ribosomes


  Organelles responsible for protein synthesis.
• Chloroplasts

  Organelles in plant cells where photosynthesis occurs.
• Permanent Vacuole

  Large sac within plant cells that stores substances and maintains rigidity.
• Cell Wall


  Rigid structure outside the cell membrane providing support and protection.
• Plasmids

  Small rings of DNA found in bacterial cells.
• Cell Specialisation


  Process where cells develop specific structures to perform specialized functions.
• Differentiation

  Process where cells acquire specific features to suit their roles.
• Stem Cells

  Undifferentiated cells capable of developing into various cell types.
• Mitosis

  Cell division process producing two identical daughter cells.
• Microscopy

  Technique of using microscopes to view small structures like cells.
• Light Microscope


  Microscope using light to magnify and view specimens.
• Electron Microscope

  Microscope using electrons to visualize specimens with high resolution.
• Resolving Power

  Ability of a microscope to distinguish between two points.
• Magnification


  Enlargement of an object's image for detailed observation.
• Transmission Electron Microscope (TEM)

  Type of electron microscope producing 2D images of sub-cellular structures.
• Scanning Electron Microscope (SEM)

  Type of electron microscope creating 3D images at slightly lower magnification.
• Calculation of Size

  Formula: size of image/magnification = size of object.
• Robert Hooke


  Scientist who first observed cells in cork using a light microscope in 1665.
• Size of an object

  Image size/magnification = object size
• Standard form

  Representation of very large or small numbers using powers of 10
• Culture medium

  Contains carbohydrates, minerals, proteins, and vitamins for growing microorganisms
• Nutrient broth solution

  Suspension of bacteria mixed with sterile nutrient broth for growth
• Agar gel plate


  Plate where bacteria form colonies on agar as culture medium
• Incubation

  Storing the plate for a few days for microorganisms to grow
• Autoclave


  Device used to sterilize Petri dishes and culture media
• Inoculating loops

  Wire loops sterilized by passing through a flame for transferring microorganisms
• Anaerobic bacteria

  Harmful bacteria that grow without oxygen
• Binary fission

  Bacteria multiplying by splitting into two
• Antibiotics

  Substances used to test effects on bacterial growth
• Inhibition zone

  Clear area around antibiotic discs showing bacterial death
• Cross-sectional areas

  Areas calculated using the formula πr², where r is the radius