Stimulus Effector Control System

Homeostasis ❖ Is the regulation and maintenance of internal environment within the narrow ranges that are necessary to support life at cellular level. This Photo by Unkno wn Author is licensed under CC BY-SA Control system diagram An example of a homeostasis 1. stimulus is body temperature regulation: . Stimulus: A drop in external temperature causes the body's internal temperature to decrease. Stimulus –anything from the internal or external environment that causes in balance in body system . 2. Receptor: Thermoreceptors in the skin and brain detect the change in temperature. 3. Control Center: The hypothalamus in the brain processes this information and determines the need to increase body temperature. 4. Effector: The body responds by triggering mechanisms such as shivering (muscle contractions generate heat) and constriction of blood vessels near the skin to conserve Example –Given stimulus –hot temperature, then the body is sweating • Receptor—thermos receptors in the skin. They detect increase in temperature. They send signals to hypothalamus in the brain / control center---------------------------------------------------------------------------------------------------------------------------------------------------• Control center ---hypothalamus in the brain triggers responses / sweating/ to help the body down and maintain homeostasis.---------------------------------------------------------------------------------------------------------------------------------------------- • effector –sweat glands produce sweat which evaporates from the skin, removing heat and cooling the body--------------------------------------------------------------------------------------------------------------------------------------------------- Activity 1- use stimulus as –temperature drop in the body . Then give an examples of receptors , control system and effectors that contribute for the maintenance within the normal range. . Thermo receptors in the skin • Receptor------------------------------------------------------------------------------------------------------------------------------------------------------ Brain • Control center -------------------------------------------------------------------------------------------------------------------------------------------------Shivering Galnds • effector ----------------------------------------------------------------------------------------------------------------------------------------------------- Activity 2 -Given stimulus –sound stimulus – hearing a loud noise. Eardrums • Receptor-----------------------------------------------------------------------------------------------------------------------------------------------------Brain/Hypothalmus • Control center -------------------------------------------------------------------------------------------------------------------------------------------------- The Cochlea in the ear • effector ----------------------------------------------------------------------------------------------------------------------------------------------------- Activity 3-Given stimulus : chemical stimulus –smelling food and starting to salivate Smell receptors in your ears • Receptor-----------------------------------------------------------------------------------------------------------------------------------------------------• Control center Brain/Hypothalmus -------------------------------------------------------------------------------------------------------------------------------------------------- Salivary Glands • effector ----------------------------------------------------------------------------------------------------------------------------------------------------- Activity 4-given stimulus –stepping on a sharp object and withdrawing your foot Pain Receptors • Receptor------------------------------------------------------------------------------------------------------------------------------------------------------ Spinal Cord • Control center -------------------------------------------------------------------------------------------------------------------------------------------------- Leg Muscles • effector ----------------------------------------------------------------------------------------------------------------------------------------------------- Activity 5-given stimulus- touch stimulus – touching a hot surface and quickly pulling your hand away Sensory Neurons • Receptor------------------------------------------------------------------------------------------------------------------------------------------------------ Brain/Hypothalamus • Control center -------------------------------------------------------------------------------------------------------------------------------------------------- Hand Muscles • effector -----------------------------------------------------------------------------------------------------------------------------------------------------