Homeostasis and response

• Negative feedback loops involve an initial change that triggers a reaction leading back to its original state.
• The nervous system is responsible for controlling homeostasis, while hormones regulate it indirectly by influencing other systems.
• Homeostatic mechanisms are the body's ways to maintain internal conditions within narrow limits.
• Homeostatic mechanisms are controlled by negative feedback loops.
• The hypothalamus is responsible for regulating body temperature through thermoreceptors located throughout the body.
• Temperature regulation involves maintaining core temperature at around 37°C through sweating or shivering.
• Blood glucose levels are controlled by releasing insulin from pancreatic cells into the bloodstream.
• Thermoreceptors send signals to the hypothalamus when there is a deviation from normal body temperature.
• If the core temperature drops below normal, heat-producing muscles contract, blood vessels constrict, and shivering occurs.
• Hormonal control involves the release of hormones from endocrine glands into the bloodstream, which travel to target cells where they bind to receptors on cell surfaces or inside the cell.
• When the core temperature rises above normal, sweat glands secrete more sweat, blood vessels dilate, and sweating increases.
• Endocrine glands produce hormones that enter the bloodstream and affect distant organs.
• Sweat glands release sweat when the body gets too hot, which evaporates from the skin surface and cools the body down.
• 2 types of effectors?

  Muscles which contract.

  Glands which release hormones.