15 Multicellular organisms develop from a single cell, which is called a zygote.
16 The zygote divides continuously to form an embryo
17 Cellular differentiation: occurs when the cells of the embryo divide and begin to differ in shape, size, contents and function.
18 What do we call plants’ stem cells? Meristems or meristematic cellsLocated at root tips, terminal and lateral buds of plants
19 Stem CellsA Stem cell is a cell that can differentiate into many different types of specialized cells.
20 There are 2 types of stem cells in animals: 1) Embryonic Stem Cells:taken from the embryonic stagecan differentiate into any type of cell.
21 2) Tissue or Adult Stem Cells: found in certain specialized tissue Can differentiate into ONLY certain types of cells.Ex. Bone marrow tissue stem cells can differentiate into white or red blood cells, platelets and many other types of cells.
22 Stem Cell Applications To study developmentAids our understanding of how normal development and abnormal development occurs.May lead to therapies for diseases and birth defectseg Cleft palate
23 Stem Cell Application To replace damaged cells and treat diseases Treat burnsTo replace blood in leukemia patientsPossible future application: replaced damaged tissues for Parkinson's disease, stroke, heart disease and diabetes.
24 Stem Cell Application To study disease Stem cells, engineered to contain the diseased gene are used to model & understand the disease process
25 Stem Cell ApplicationCould provide a resource for testing new medical treatmentsNew medications could be tested for safety on specialized cells generated in large numbers from stem cell lines – reducing the need for animal testing.
26 What are the ethical issues around stem cell usage? Stem cell research is controversial and involves moral and ethical dilemmas for many peopleWhat are the ethical issues around stem cell usage?
27 Watch: The role of stem cells (12 mins) Go toUsername: calctorPassword: calctorPut in keyword: “Clone the role of stem cells”Click and watch; make sure speakers are on