Kinesiology 2241A/B Study Guide - Midterm Guide: Extrafusal Muscle Fiber, Parasympathetic Ganglion, Alpha Motor Neuron

• School: Western University
• Department: Kinesiology
• Course: Kinesiology 2241A/B
• Professor: Daniel Bechard

Document Summary

Describe the hormones involved in the feedback pathway that modulates the levels of thyroid hormones in the blood: If you have too much thyroid hormones you can get very sick, so we use negative feedback mechanisms to regulate it. Shut down trh until we get back to normal= negative feedback. Too much trh can be secreted disobeying negative feedback. Tsh is stimulus for follicular cells to grow- that"s why thyroid enlarged when too much thyroid hormones are secreted. Graves disease: antibodies may act like tsh. When you over stimulate the thyroid, tends to grow. Iodine is needed- pituitary damage pituitary lacks tsh, if you don"t have. Too low thyroid hormones, more trh and tsh gets produced. It should produce t3 and t4 after this, but since there"s not enough iodine t3 and t4 can"t be made. Therefore, there"s an excess amount of trh and tsh and the body doesn"t know what to do.