cell specialization snc2d1 cells, tissues and organs
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Cell SpecializationSNC2D1 Cells, Tissues and Organs
Why Specialize?A single cellular organism performs all required functions in one cell.e.g., Amoeba.
Why Specialize?Multicellular organisms are much more complex. The body needs to supply food and nutrients, transport materials, remove wastes and fight infection.
Cellular DifferentiationThe process of creating specialized cells.All cells in the body originated from the zygote undergoing mitosis.As an embryo develops, cells change their shape, contents and function.
What Causes Specialization?1. Cytoplasm Differences:Asymmetric distribution of organelles & other factors in zygote.Results in different daughter cells.
What Causes Specialization?2. Environmental Conditions:Variations in temperature and nutrients.
3. Neighbouring Cells: Substances produced by nearby cells can diffuse to nearby cells.
What Causes Specialization?The three factors listed may result in the expression of different genes within a cell.
Abnormal DevelopmentChemical contamination of the environment can affect cellular development.
Stem CellsCells that can differentiate into many different cell types. The daughter cells have the same DNA, but different genes may be turned on or off.Watch This!!!
Types of Stem CellsEmbryonic Stem CellsDifferentiates into any cell type.
2. Adult Stem CellsExists in some tissues but can only form specific types of cells. E.g., bone marrow stem cells form white blood cells, red blood cells and platelets.
Stem Cell Research
Tissue TypesTissues are a collection of similar cells that perform specific functions.Animals have 4 types of tissue:1. Epithelial.2. Muscular.3. Connective.4. Nervous.
Epithelial TissueLine the internal and external surfaces of the body. Form a barrier by connecting adjoining cell membranes.
Muscular TissueMove the body or organ by contracting and relaxing.
Connective TissueStrengthens, supports and protects other tissues.Cells are in an extracellular matrix.
Nervous TissueMade of neurons with long projections that send and receive signals.Coordinates body actions.
Tissues in the Arm
Tissues AssignmentRead the handout Tissues of the Human Body and learn the tissue subtypes.Answer the questions on the handout.