3.2.1.

Cards (55)

  • Cell Surface Membrane
    Controls the exchange of materials between internal and external environment.
    • Partially permeable.
    • Phospholipid bilayer.
  • Nucleus
    An organelle that stores the genetic information of the cell
    • Contains Chromosomes; protein-bound linear DNA
    • May have more than one nucelolus
  • Nucleolus
    Contains all genetic information; chromasomes
    • Site of ribosome production
  • Nuclear Envelope
    Double membrane surrounding the nucleus.
  • Nuceloplasm
    Granular jelly-like material
    • Makes up the bulk of the nucleus
  • Rough Endoplasmic Reticulum
    Processes proteins made by ribosomes
    Large surface area
    • Surface covered in ribosomes
    • Continuous folds of membrane connected to the nuclear envelope
  • Nuclear Pores
    Allows molecules in and out of the nucleus
  • Smooth Endoplasmic Reticulum (ER)
    Does not have ribosomes on the surface 
    • Production, processing and storage of lipids, carbohydrates and steroids.
  • Mitochondria
    Site of aerobic respiration within eukaryotic cells
    • Surrounded by double membrane
  • Cristae (Mitochondria)
    The folded inner membrane
    • Forms the matrix
  • Matrix (Mitochondria)
    Contains enzymes needed for aerobic respiration
    • Produces ATP
    • Contains small circular pieces of DNA (mitochondrial DNA)
    • Contains ribosomes (needed for replication)
  • Chloroplast
    Site of photosynthesis
    • Larger than mitochondria
    • Double membrane
    • Membrane-bound compartments
  • Nucleus Structure
    • Surrounded by nuclear envelope; semi-permeable double membrane
    • Nuclear pores allow substances to enter/exit
    • Dense nucleolus made of RNA & proteins assembles ribosomes
  • Function of nucleus
    • Contains DNA coiled around chromatin into chromosomes
    • Controls cellular processes; gene expression determines specialisation and site of mRNA transcription, mitosis, semi-conservative replication
  • Mitochondrion structure
    • Surrounded by double membrane
    • Folded inner membrane forms Cristae; site of electron transport chain
    • Fluid matrix; contains mitochondrial DNA, respiratory enzymes, lipids, proteins
  • Chloroplast structure
    • Vesicular plastid with double membrane
    • Thylakoids; flattened discs stack to form grana; contains chlorophyll
    • Lamellae; tubes attaching thylakoids to adjacent grana
    • Stroma; fluid in matrix
  • Function of mitochondria
    Site of aerobic respiration to produce ATP
  • Chloroplasts
    Site of photosynthesis to convert solar energy to chemical energy.
  • Golgi apparatus function
    • Modifies and packages proteins for export
    • Synthesises glycoproteins.
  • Lysosome Function
    • Digests contents of phagosome
    • Exocytosis of hydrolytic enzymes
  • Ribosome structure
    • Formed of protein & rRNA
    • Free in cytoplasm or attached to ER
  • Ribosome function
    Site of protein synthesis via translation
    • Large subunit; joins amino acids
    • Small subunit; contains mRNA binding site
  • Endoplasmic Reticulum (ER) Structure
    Cisternae; network of tubules & flattened sacs extended from cell membrane through cytoplasm & connects to nuclear envelope
  • Endoplasmic Reticulum (ER) Function
    • Rough ER; many ribosomes attached for protein synthesis and transport
    • Smooth ER; lipid synthesis
  • Cell wall (Plant) Structure
    Made of Cellulose Microfibrils
    • Plasmodesmata; allows molecules to pass between cells
    • Middle lamella; a boundary between adjacent cell walls
  • Cell wall (Bacteria) Structure

    Made of the polysaccharide murein
  • Cell wall Function
    • Mechanical strength and support
    • Physical barrier against pathogens
    • Part of apoplast pathway (plants) to enable easy diffusion of water
  • Cell vacuole Structure
    • Surrounded by single membrane
    • Tonoplast; contains cell sap, mineral ions, water, enzymes, soluble pigments.
  • Cell vacuole Function
    • Controls turgor pressure
    • Absorbs and hydrolyses potentially harmful substances to detoxify cytoplasm.
  • Role of plasmids in prokaryotes
    • Ring of DNA that carries non-essential genes
    • Can be exchanged between bacterial cells via conjugation
  • Role of Flagella
    Rotating tail propels
    • Corkscrew motion
  • Role of the capsule
    Polysaccharide layer
    • Provides mechanical protection
    • Sticks cells together
  • Cell wall (Fungi)
    Chitin
  • Viruses
    Acellular & non-living
    • No cytoplasm
    • Cannot self-reproduce
    • No metabolism
  • Viral particle structure
    • Linear genetic material (DNA or RNA) & viral enzymes e.g. reverse transcriptase
    • Surrounded by capsid (protein coat made of capsomeres)
    • No cytoplasm
  • Structure of enveloped virus
    • Simple virus surrounded by matrix protein
    • Matrix protein surrounded by envelope derived from cell membrane of host cell
    • Attachment proteins on surface
  • Role of capsid on viral particles
    • Protects genetic material
  • Role of attachment proteins on viral particles
    Enable viral particles to bind to complementary sites on host cell
    • Entry via endosymbiosis
  • How to prepare a temporary mount of tissue for an optical microscope
    1. Obtain thin section of tissue
    2. Place plant tissue in a drop of water
    3. Stain tissue on a slide to make structures visible
    4. Add coverslip using mounted needle at 45 degrees to avoid trapping air bubbles.
  • Optical Microscope
    + Colour Image
    + Can show living structures
    + Afforable
    2D
    — Lower resolution than EM