cell division

• what is a stem cell?

  Undifferentiated cell. That can differentiate into one or more specialised cell types.
• what's an adult stem cells?

  Stem cells, some adults that could only differentiate into certain specialised cells
• where are the adults stem cells found?

  Bone marrow
• what are embryonic stem cells?

  Stem cells from embryos that can differentiate into any specialised cell
• where are embryonic stem cells found?

  Only human embryos usually from spare embryos from fertility clinic
• what is a therapeutic clothing?


  Parent cells are used to create an early embryo clone of themselves cells from the embryo can then be used to treat the patient's medical conditions
• give one advantage of using therapeutic clothing

  Stem cells from embryo are not rejected when transplanted because they have the same gene as patient
• j one advantage of using adult stem cells

  Fewer ethical issues as obtained from adults who can consent to their use
• disadvantages of using adult stem cells

  Can take a long time for a suitable donor to be found

  Can only differentiate into some specialise cells so can treat fewer diseases
• give two advantages of using embryonic stem cell

  They can differentiate into any specialised cell so it can be used to treat many diseases

  Easier to obtain as they have found in spare embryos from fertility clinics
• give two disadvantages of using embryonic stem cells

  Ethical issues surrounding their use as every embryo is a potential life

  Potential risks involved with treatment such as transfer of viral infections
• what are plant Meri stems?

  An area where rapid cell division occurs in the tips of roots and shoots
• give two advantages of using plant Meristems to clone plants

  Where species can be claimed to protect them from extinction

  Plants with special features can be cloned to produce many copies
• give one disadvantage of using plant meri stems to clone plants

  No genetic variation
• what is cell division by mitosis?

  Body cells divide from two identical daughter cells
• what is the purpose of mitosis?

  Growth and repair and asexual reproduction
• what happens during the first stage of the cell cycle?

  The cell grows bigger the chromosomes duplicate the number of sub cellular structures increase
• what happens during Mitosis

  One set of chromosomes is brought to each end of the cell and the nucleus divides
• what happens during the third stage of the cell cycle?

  The cytoplasm in the cell membrane divide forming two to identical daughter cells