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The diversity of cellular life. Colonies of primitive unicellular organisms don’t show emergent properties. Prokaryotic organisms or primitive eukaryotic organisms (algae, protistae ) exist in colonies of identical cells
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Colonies of primitive unicellular organisms don’t show emergent properties • Prokaryotic organisms or primitive eukaryotic organisms (algae, protistae) exist in colonies of identical cells • While the cells co-operate, they do not fuse to form a single mass and so don’t form a single organism • Each cell has identical structure and function
Multicellular organisms have differentiated cells Cells are specialised: • Blood cells • Muscle cells • Retinal cells • Glandular cells • Epithelial cells Each cell type has a special task and structure Each cell has the same DNA, but only a section of it is expressed
Levels of ‘organisation’ in a multicellular organism • CELL • TISSUE • ORGANS • ORGAN SYSTEMS
4 key animal tissue types • Epithelial • Connective • Muscle • Nervous
Simple: just one layer or cell shape Stratified: multiple layers and cell shapes Classes of Epithelia Human Anatomy, Larry M. Frolich, Ph.D.
“ciliated” literally = eyelashes (see next page)
CONNECTIVE TISSUES • “Areolar tissue” as model • Universal in body • Underlies epithelium, supports capillaries, small nerves
Cells of Connective Tissues • Fibroblasts make fibres – cartilage, ligaments, blood, bone • Immune cells in areolar tissue
Different types of Connective tissues Dense • Ligaments • Cartilage • Bone Loose • Fat • Areolar Human Anatomy, Larry M. Frolich, Ph.D.
Tissue types 3. Muscle tissue • Skeletal • Cardiac • Smooth
Tissue types 3. Nervous tissue • Skeletal • Cardiac • Smooth
Cell Differentiation • Harvard Animation
What are stem cells? • Cells that are able to generate more specialised types of cell types through the process of cell differentiation • Cells that can divide to make identical copies of themselves, through self-renewal • You can learn all about stem cells by watching the beautiful animation from Utah Genetics here: • Stem Cells
Different types of stem cells 1. Embryonic Stem Cells • Here, you can learn how embryonic stem cells are made: • Quck guide to Embryonic stem cells • Here is the BBC video on how embryonic stem cells are made: • How to make stem cells
Different types of stem cells 2. Somatic Stem Cells • (also called adult stem cells) • Exist naturally in the body • Used for bone marrow transplants • Can only differentiate into dedicated cell types
Stem cells in the adult brain:Are they still working for us now?
Different types of stem cells 3. Induced pluripotential Stem Cells • Created artificially in the lab by ‘reprogramming’ a patients own cells • Made from patient’s own cells – fat, skin, fibroblasts • Can become any cell in the body (even a whole mouse!)
Induced pluripotential Stem Cells – The future! • Learn the story of iPS stem cells from Utah Genetics… • IPS stem cells
Stem Cells used in medicine: Treatment of leukaemia • Stem cell transplants have been successfully used since 1968 to treat patients with leukaemia • Patients with leukaemia first have their own abnormal blood cells destroyed by radiotherapy • Then the patients own bone marrow stem cells are replaced with a transplant (into the bloodstream) from a healthy patient’s bone marrow • If the transplant is successful, then the stem cells will migrate into the bone marrow and begin to produce new, healthy leucocytes • You can learn all about leukaemia treatment by linking here onto Utah Inc: • Utah Genetics
What can we use Stem Cells for? • To provide lab-grown human or animal tissue for identifying new treatments for disease (rather than using animals in research) • TO produce new human tissue and organs to replace damaged ones • To repair tissue by stimulating stem cells already in the body • To use stem cells from patients with inherited genetic diseases (e.g. cystic fibrosis, some forms of Parkinson’s disease) to study the disease • To better understand diseases like cancer • To investigate human development
Stem Cell Research is a fast-moving subject • Stem cell grandparents • Brand new sperm • First trial of human embryonic stem cells • Tracheal transplant • Stem cell nobel prize
Links on ethics related to Stem Cell research • Stem Cell Ethics Factsheet • Ethics and Embryos Factsheet • Are embryos human? – a conversation…