biology

?
  • Created by: omer3
  • Created on: 27-05-15 21:43
View mindmap
  • mitosis and cancer
    • cells in multi cellular organsims only divide when required otherwise they enter phase g0 of cellcyce whereno division occurs
      • If a cell is no longer required or a mutation is detected the cell may enter apoptosis a process of controlled cell death in which organelles break down and the cell disintegrates into membrane bound packages
        • if a cell enters the cell cycle unneccesarily and isnot terminated by apoptosis it can divide uncontrallbly leading to formation of a tumor and cancer
          • cancer can be detected by searching fort abnormal cells in cervical smear tests if diagnosed early it can be treated cancer treatments aim to destroy tumors ithout affecting surrounding cells
    • animals tissue and organs
      • animals begin life as a single cell a zygote these eventually divide by mitosis froming a multi cellular organsim
        • embryonic stems cells are cells which are initally unspeciallised but have the ability to divide and become new cells
          • each cell in organism contain the full genome of the organsimhowever with specialised cells only genes neccessry for the cvells function are switched on these specialised cells are unable to produce other types of cell
            • specialised cells join together to form tissues each tissue is specialised to carry out a particular function
              • eg 4 main types of animal tissue
                • connective tissue which ads support and syructure to bones and blood
                • eptitlelil tissue whivch lines body surfces such organs vessels
                • Untitled
                • muscle tissue is used gfor move,ent
                • nerve tissue isused as communication between cells
              • tissues are organised into organs é or more tissuers work toghther towards a common purpose eg lungs stomach
              • organs are organised into organ suystems which are é or more ogans working tooghter towards a common purpose
      • all cells of flowering plants are originally from from meristematic  these are unspecialised  cells which constantly divide  plant equivalent of stem cells
        • meristems of the plant are located at the apex of the shoot and root tip
        • there ' types of plant tissue
          • protective tissue such as the epidermis of the leavrs
          • packaging tissue such as parenchyma which fills the space in between tissues can be used as adaptation for function such as photosynthesis or storage
          • mechanical tissue which contains cells with exyracellulose which provide extra streghth and flexibility

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Cellular processes resources »