Hormones

• Parasympathetic motor nerve fibers are responsible for the rest and digest.
• Acetylcholine is the major neurotransmitter in the parasympathetic nervous system.
• Under parasympathetic conditions pupils constrict.
• Luteinizing hormone surges at the time of ovulation, which occurs in the middle of the menstrual cycle at day 14
• The initial hormone in the menstrual cycle is FSH, then in response, Estrogen is released; during ovulation (day 14), luteinizing hormone is released. After ovulation, progesterone is released.
• Parathyroid Hormone (PTH) increases calcium levels.
• Negative Feedback occurs when the product or result of a pathway acts to inhibit that pathway.
• Positive feedback occurs when the product or end result of a pathway acts to stimulate that pathway.
• Cascade pathways are commonly seen when a signal is being amplified.
• Glucagon is released by the pancreas
• LH hormone is released by the anterior pituitary gland
• Paracrine signaling involves the release of molecules from one cell, which then must diffuse a short distance before binding to receptors in a nearby cell.
• Autocrine signaling is defined as the production and secretion os a signaling molecule that binds to receptors on the same cell
• Juxtacrine signaling involves direct, simultaneous contact between signaling molecules and two adjacent cells.
• Steroid hormones diffuse through the cell membrane and enter the nucleus to act as a transcription factor.
• Peptide or amino acid-derived hormones require a second messenger. These hormones are usually recognizable by the suffix -in or -ine
• Thyrotropin-releasing hormone (TRH) is a tropic hormone, released by hypothalamus and causes the release of another hormone (TSH)
• Aldosterone increases water reabsorption in the kidneys by increasing sodium reabsorption.
• Cortisone increases blood glucose concentrations, decreases protein synthesis, and acts as an inflammatory
• Peptide hormones are polar molecules and are unable to cross cell membrane and are typically bind to extracellular receptors.
• Steroid hormones can pass through cell memebrane
• Fatty acid breakdown, as well as inhibition of liver glucose uptake, are functions of growth hormone, or somatotropin.