Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Extracellular matrix wikipedia , lookup
Cell growth wikipedia , lookup
Signal transduction wikipedia , lookup
Tissue engineering wikipedia , lookup
Cell culture wikipedia , lookup
Cell encapsulation wikipedia , lookup
Cellular differentiation wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
Cells • All organisms are made up of cells • Cells have particular properties – Discrete Boundaries – each cell has a membrane – Metabolism – each cell uses energy and creates waste – Replication – Function – Communication Hormones • Provide cell communication • Indirect communication – signaling (like radio). This is called endocrine activity. • Direct communication. This is called paracrine activity. Cell Properties • Each cell (except sex cells) contains identical DNA. • Every cell has a complete set of instructions on how to work like any other cell. • Redundant • Why don’t all cells operate like all other cells? Cell Communication • Certain cells have receptors so that they can receive signals from proteins. Like puzzle pieces. • Hormones are proteins – each with a particular shape. Thyroid Function Thyroid gland (T3 and T4) controls cell metabolism, i.e., how the cell uses energy. • Hypothalamus monitors the secretions of the thyroid gland (T3 and T4). If levels aren’t correct, then produces TRH. • Pituitary gland (area called the adenohypophysis) has TRH receptors. TRH signals pituitary to produce TSH. • Thyroid gland has TSH receptors, signaling it to produce T3 and T4. Hypothalamus TRH T3, T4 Negative Feedback Thyroid Pituitary TSH Thyroid Function Diabetes • Cells produce energy from glucose • Insulin allows glucose to get from the bloodstream into the cells • Insulin is produced by the pancreas (Islets of Langerhaus) • When blood sugar increases, this causes the pancreas to secrete insulin • Diabetes – when body can’t make and/or use insulin Diabetes • Type I – Juvenile diabetes: Immune system attacks and destroys insulin producing cells of the pancreas • Type II – Adult onset: Cells don’t respond to insulin, insulin resistance • Without glucose, cells burn fat for energy which creates ketones. • When ketones build up in cells, they can poison cells. Diabetes • Insulin Shock – too much insulin • Neurons (i.e., your brain) also depend on glucose as their source of energy. • Neurons don’t need insulin to absorb glucose • When too much insulin, then cells absorb all the available glucose, leaving none for the neurons. • Dizziness, speech impairment, loss of consciousness – hypoglycemic coma