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Science exam revision - Coggle Diagram

- - - - Nucleus - Contains all genetic material inside cell, controls cell activities
        
        In eukaryotic cells (animal and plant cells) However in prokaryotic cells (bacterial cells) They have genetic material not stored in a nucleus, but in a single circular strand known as a plasmid
      - Cytoplasm - Jelly-like substance inside cell, Where most chemical reactions occur
        
        In eukaryotic and prokaryotic cells (animal, plant and bacterial cells)
      - Ribosomes - Where protein synthesis occurs
        
        Found in eukaryotic cells (Animal and plant cells)
      - Mitochondria - Where aerobic respiration occurs, provides energy for the cell
        
        Found in eukaryotic cells (Animal and plant cells)
      - Cell membrane - Controls what enters and leaves the cell
        
        Found in Eukaryotic and prokaryotic cells (Animal, Plant and Bacterial cells)
      - Cell wall - Made from cellulose, Provides strength to the cell
        
        Found in Plant cells and prokaryotic cells (Bacterial cells)
      - Chloroplasts - Where photosynthesis takes place providing food for the plant, Contains chlorophyll pigment (which makes it green) Which harvests light needed for photosynthesis
        
        Found in only Plant cells
      - Permanent Vacuole - Contains cell sap, Found within cytoplasm, Improves cells rigidity
        
        Found in only Plant cells
    - - Eukaryotic cell: Cells that have DNA stored inside of a Nucleus,
      - Prokaryotic cell: Cell that does Not have DNA stored inside of a Nucleus, it is smaller than Eukaryotic cells.
    - - Cell Differentiation is when a cell becomes specialised. A cell usually becomes specialised once in there lifetime usually in the early stages of development of the organism but some cells can differentiate throughout there lives (These are called adult stem cells) these cells are found in bone marrow and can be used to treat diseases like leukaemia.
      - Types of specialised cells and there functions and adaptations
        
        Sperm cell
        
        Function: To fertilise the egg
        
        Adaptations to help with this: Flagellum (tail) to allow it to swim, Lots of mitochondria to provide it energy to swim, digestive enzymes so it can break down the outer layers of the egg (stored in the acrosome)
        
        Palisade cell:
        
        Function: To absorb light and carry out photosynthesis in a plant
        
        Adaptations to help with this: Lots of chloroplasts which contain chlorophyll (a green pigment used to absorb light. These organelles carry out photosynthesis.
        
        Xylem cell:
        
        Function: To transport water and minerals around the plant
        
        Adaptations to help with this: Long cells with walls toughened by lignin, form long hollow tubes made from dead tissue, Water and minerals flow from the roots towards the leaves only in one direction in a process called TRANSPIRATION.
  - - - Image size = actual size x magnification
      - Actual size = image size DIVIDED BY magnification
      - Magnification = image size DIVIDED BY actual size
    - - A scientist named Leeuwenhoek was quite an important figure in the history of microscopes. He was not the first person to build a microscope but the ones he built were the best of his time period. It used only on lens. He gained much of his inspiration from reading Robert Hooke's book Micrographia. **Robert Hooke was the person who named and discovered cells.
      - The word Microscope comes from two words, 'Micro' meaning small and 'scope' meaning view.
    - - Light microscope
        
        PROS
        
        Relatively cheap, can magnify live specimens and can be used almost anywhere
        
        CONS
        
        They can only magnify around 2000x (and school microscopes, that is reduced to several hundred times).
      - Electron Microscope
        
        PROS
        
        Magnify up to 2,000,000 times, can see subcellular structures with, can give dramatic 3-D images
        
        CONS
        
        Large, Very expensive, cannot magnify live specimens, Have to be kept in humidity and temperature controlled rooms.
- - - - Electron = -1
      - Neutron = 0
      - Proton = +1
    - - If atoms gain electrons when turning into an ion, it will have a negative charge, by however many electrons it has gained. If it gains 2 electrons for example, the atom will have a charge of -2. However if an atom loses some electrons, it will have a positive charge. For example if an atom loses 2 electrons, it will have a charge of +2