Biology topic 3 ( cell division)

• How is genetic material organised in the nucleus?

  -Nucleus has chromosomes (23 pairs)

  -Chromosomes are made of DNA molecules

  -Chromosomes carry lots of genes
• Where in the human body can stem cells be found that only differentiate into blood cells

  Bone marrow
• Advantages of embryonic stem cells

  -Can differentiate into any cell
• Disadvantages of embryonic stem cells

  -Unethical

  -Can be rejected by the immune system
• Advantages of using adult stem cells

  -Cannot be rejected as its the patients own cells

  -more ethical as people can consent
• Disadvantages of adult stem cells

  -Can only differentiate into blood cells (only treat a couple of diseases such as ammonia )
• Stages of cell cycle

  1.Cell grows bigger. Amount of organelles multiplies.

  2.All 23 pairs of chromosomes get pulled to each end of the nucleus and it divides

  3. the cell membrane and cytoplasm splits forming identical cells
• Where can stem cells be found in plants?

  in meristem
• How are nerve cell specialised?

  1.Long axon - transmits electrical impulses in long distances

  2.many dendrites - help make connections with neurons