stem cells

• 2 things stem cells are able to do?
• where are adult stem cells extracted from Bone marrow
• 3 features about ASC - can divide by mitosis - can only differentiate into different types of blood cells (WBC, RBC, PLATELETS) - can replace damaged cells to keep us alive but they don't form new tissues
• whats one cancer of the bone marrow? Leukaemia - a type of cancer
• how to treat a infected bone marrow? - 3 steps the patient's original bone marrow is destroyed using radiationpatient recieves a transplant of bone marrow from a donor stem cells in the BM divide and form new BM= they also differentiate and form blood cells.
• 2 problems with bone marrow transplant? donor has to be a compatible with patient or the WBC produced by the donated BM could attack the bodyrisks of viruses passed from donor to patient
• where are plant stem cells found? found in plant tissues called the meristem
• where are meristems found? areas of the plants that are continually growing like the tips of the roots and shoots
• what happens as plants grow in plant stem cells? unspecialised stem cells will differentiate into all of the cells and tissues that the plant needs like the palisade cells that do photosynthesis, pholem and xylem cells for transportation or root hair cells for absorption
• do plant stem cells continue plants entire life or do they disappear when fully developed continue
• how to stop a plant from going extinct? can clone it or produce cloned crop plants for farmers
• how to replace faulty cells for stem cells? 4 steps extract embryonic stem cells from early embryosgrow them in a laboratorystimulate them to differentiate into any type of specialised cellgive to a patient to replace their faulty cells
• 3 things faulty cells cause type 1 diabetesparalysissickle cell anaemia
• how is sickle cell anaemia caused? misshapen RBC
• How is type 2 diabetes caused? damage to the pancreas cells that normally produce insulin
• how is paralysis caused? When nerve cells are damaged, messages can no longer be sent to the muscles properly. This can lead to the loss of the ability to move some or all of your body.
• how to cure diabetes/ paralysis/ anaemia? 1. scientists would take some embryonic stem cells and grow them in a laboratory 2. stimulate them to differentiate in the pancreas cells for diabetes/ blood cells for anaemia/ nerve cells for paralysis 3. inject those cells into the patient's pancreas where they can continue to divide and produce the insulin for diabetes that the patient needs.
• 3 limitations of stem cells 1. requires embryonic cells(only ones that can differentiate into any type of cell) (usually unwanted embryos or have been destroyed) 2. limited supply of embryos 3. ethical issues = human embryos that are being used have the potential for human life - taking a life - beneficial for curing existing and future people
• are embryonic stem cells legal or illegal in the UK? legal but tighly controlled and scientists have to follow strict rules
• why might some patients reject embryonic stem cells? different genomes of embryo and patients= patient immune system may reject stem cells = it may try to destroy them beacuse it identifies them as foreign
• how to reduce the risk of rejection in embryonic stem cells? giving patients medications to suppress their immune system= doesn't always work and has side effects
• 3 alternative pathway other than using embryonic stem cells? - use adult cells - easy to get - won't cause rejection= can be taken from patients themselves - can only differentiate into type of blood cells = can treat sickle cell anaemia but not diabetes or paralysis - there is new research exploring how we could use adult stem cells to produce any type of cell
• how might virus transmission happen in stem cell in medicine? if donor stem cells are infected with a virus, when transferring it into a patient the virus also goes into the patient which can infect the patient
• how might a tumour develop using any type of stem cells in medicine? because stem cells can divide so quickly, theres a chance that they could get out of control once been transplanted into the patient= can develop a tumour or cancer
• what is therapeutic cloning? embryo is produced with the same genes as the patient.
• what happens in therapeutic cloning? Stem cells from the embryo are not rejected by the patient’s body so they may be used for medical treatment once inside the patient, the stem cells can differentiate to replace cells which have stopped working properly
• what can therapeutic cloning be used for? diabetes or paralysis