Unformatted text preview: BIO 201 Life, Chemistry and Homeostasis Human Anatomy and Physiology The Macromolecules Homeostasis Anatomy and Physiology Observation of structure Gross anatomy is what is visible with naked eye Histology is examination of cells/tissues with microscope Study of bodily functions Comparative physiology involves the study of different species Basis for the development of new drugs and medical procedures Life, Chemistry and Homeostasis 1 BIO 201 All life... Uses energy (metabolizes) Metabolism is the sum of ALL chemical and physical processes occurring within a cell Uses raw materials and removes waste products Maintains homeostasis Is composed of cells Responds to the environment Exhibits development (growth or differentiation) Can reproduce Evolves E l Changes are passed down to descendants over time The Macromolecules (Biomolecules) A. B. C. D. Carbohydrates Proteins Nucleic acids Lipids Life, Chemistry and Homeostasis 2 BIO 201 Carbohydrates Hydrophilic molecule Types of carbohydrates word root sacchar- or the saccharsuffix -ose often used Monosaccharides Glucose Disaccharides Maltose Polysaccharides Glycogen Starch (amylose vs (amylose cellulose) Carbohydrate Functions Source of energy (immediate use and storage) Cell membrane component Extracellular matrix component Linked carbohydrates glycolipids external surface of cell membrane glycoproteins external surface of cell membrane mucus of respiratory and digestive tracts proteoglycans cell adhesion, gelatinous filler of tissues (eye) and joint lubrication Life, Chemistry and Homeostasis 3 BIO 201 Proteins Composed of amino acids shorter polymers aka peptides or polypeptides Can be hydrophilic or hydrophobic The amino acids in a protein determine its structure and function proteins fold up into particular shape cellular activity can change shape damage or illness can change shape some proteins have "helpers" heme group for hemoglobin Protein Functions Catalysis ALL enzymes are proteins Structure collagen, keratin Communication some hormones, cell receptors ligand - molecule that binds to a protein Membrane Transport form channels, carriers (for solutes across membranes) Recognition and protection glycoprotein antigens, antibodies and clotting proteins Movement muscle contraction Cell adhesion proteins bind cells together Life, Chemistry and Homeostasis 4 BIO 201 Nucleic Acids Hydrophilic molecule DNA blueprint for making proteins all day, every day genetic material passed on only during cell division RNA intermediate in making proteins ATP universal energy molecule Lipids Hydrophobic molecule Primary types and functions Fatty acids (energy storage) Triglycerides (aka fats and oils; energy storage) (aka Phospholipids (cell membrane component) Steroids (cellular signaling, cell membrane component) Life, Chemistry and Homeostasis 5 BIO 201 Homeostasis The body normally returns to a state of equilibrium by itself needs to detect the change and oppose it negative feedback Internal environment described as dynamic equilibrium fl fluctuates within a range i hi around a certain set point Loss of homeostatic control causes illness or death Structures Needed for Negative Feedback Receptor = structure that senses change Integrator = control center Effector = structures that carry out commands of the control center
Receptor Cells or proteins within cells Integrator Brain or spinal cord Effector Muscles or glands Life, Chemistry and Homeostasis 6 BIO 201 Human Thermoregulation Blood temperature sensed by cells in brain Information sent to hypothalamus Brain sends response to effectors in skin and muscle control shivering and sweating vasodilation with heat and vasoconstriction with cold Control of Blood Pressure Receptors in heart, aorta and carotid detect changes in blood pressure Nerve signals travel to brainstem Nerve signals speed heart and raise blood pressure (if low) or slow heart and decrease blood pressure (if high)
Blood pools Blood Pressure Time Life, Chemistry and Homeostasis 7 BIO 201 Regulation of Blood Glucose Blood glucose levels sensed by variety of cells Signals sent to pancreas If high, insulin (hormone) released tells body cells to take up glucose tells liver cells to make glycogen If low, glucagon (hormone) released tells liver to breakdown glycogen Why is homeostasis important? With Without Life, Chemistry and Homeostasis 8 BIO 201 Heat Acidity Life, Chemistry and Homeostasis 9 BIO 201 Water Homeostasis Cells in isotonic solutions keep their shape same concentration of solutes inside and outside Cells in hypotonic solutions take on water and swell or burst lower solute concentration outside than inside Cells in hypertonic solutions lose water and shrink higher solute concentration outside than inside Positive Feedback Loops Physiological change leads to an even greater change in the same direction (self-amplifying) (self Normal way of producing rapid changes birth, blood clotting, protein digestion, g , g, p g , generation of nerve signals g Life, Chemistry and Homeostasis 10 ...
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- Spring '08
- Homeostasis, Physiology The Macromolecules Homeostasis