3.4. Eukaryotic Cell Structure

Cards (67)

  • The golgi can label proteins to ensure they end up in the right destination
  • The golgi can modify proteins, often adding non-protein components such as carbohydrates
  • The proteins and lipids produced from the RER are passed through the golgi apparatus in a strict sequence
  • Vesicles: smooth rounded hollow structures
  • Membranes are folded to form cisternae because it produces a large surface area
  • Golgi apparatus contain cisternae (flattened sacs of folded membranes)
  • The golgi apparatus appears in every eukaryotic cell and is similar to that of the smooth endoplasmic reticulum
  • Lamellae of the rough endoplasmic reticulum make up the double membrane
  • The SER is more tubular in appearance and is involved in the synthesis of lipids and carbohydrates
  • The rough endoplasmic reticulum has ribosomes on the outer surface of the membranes
  • The RER provides a pathway for the transport of materials throughout the cell
  • The membranes of the RER enclose a network of tubules and flattened sacs called cisternae
  • The RER is continuous with the outer nucleus membrane
  • The RER is an elaborate, three dimensional stem of sheet-like membranes, spreading through the cytoplasm of the cells
  • Soluble products inside a golgi vesicle can be absorbed into the cytoplasm
  • The golgi has two faces: cis and trans
  • The golgi vesicles can travel to the cell surface where they can fuse with the membrane, releasing their contents to the outside
  • When sorted, the modified proteins and lipids are transported in golgi vesicles which are pinched off from the ends of the golgi cisternae
  • Chloroplast is the site of photosynthesis in eukaryotic cells, being either biconcave or planoconvex in shape.
  • Chloroplast can be found in the mesophyll of plant leaves. And are spheroid, discoid or ovoid shaped too.
  • Chloroplasts are vesicular and have a colourless centre and has ends that are filled with chlorophyll
  • Chloroplast: The outer membrane is semi porous and is permeable to small molecules and ions, diffusing easily. However, not permeable to larger proteins
  • Chloroplast: The intermembrane space is 10-20nm between the inner and outer membranes
  • Chloroplast: The inner membrane is the border to the stroma and regulates the passage of materials. Synthesising fatty acids, lipids and cartenoids
  • Chloroplast: The thylakoid system is suspended in the stroma. It is a collection of membraneous sacs. Alongside chlorophyll being found here. Chlorophyll is the site in which light reactions for photosynthesis take place
  • Thylakoids are in stacks known as granums. Granums consist of 10-20 thylakoids
  • Chloroplasts carry out the absorption of light energy then being converted into biological energy
  • Chloroplast granal membranes provide a large surface area for the attachment of chlorophyll, electron carriers and enzymes. These carry out the last stages of photosynthesis . These are ordered in a strict fashion
  • The fluid of the stroma contains all the enzymes needed in order to make sugars in the second stage of photosynthesis
  • Chloroplasts contain both DNA and ribosomes in order to be able to quickly and easily manufacture their own proteins
  • Mitochondria has a folded inner membrane so that it has a larger surface area in order to attach to enzymes and proteins needed for respiration. This is called the cristae
  • mitochondria matrix is equivalent to cytoplasm but is more liquid in nature. Containing proteins, lipids, ribosomes and DNA
  • Mitochondria has it's own ribosomes and DNA in order to control its production of proteins and enzymes and it means it is quicker to produce proteins
  • Mitochondria is the site of aerobic respiration and is the site of ATP synthesis
  • The golgi vesicles are made from lysosomes. Lysosomes contains lysozymes which digest the cell contents
  • Lysosome is an organelle containing hydrolytic enzymes used to break down macromolecules such as carbohydrates, fats and proteins
  • All plant cells have a cell wall
  • Cell walls consist of microfibrils from the polysaccharide cellulose, embedded in a matrix. Microfibrils are considerably strong so contribute to the strength of the cell wall
  • Cell walls provide mechanical strength in order to prevent the cell bursting under the pressure created by the osmic entry of water. Giving strength to the plant as a whole. Alongside contributing to the movement of water through the plant
  • Cell walls have a thin layer called the middle lamellae which is the boundary between adjacent cell walls and cements the adjacent cells together.