1 Ionophores are molecules that have been engineered by bioc

1. Ionophores are molecules that have been engineered by biochemists to increase the permeability of plasma membranes to specific ions. These molecules embed themselves in the plasma membrane and act as channels for specific ions. For experimental purposes, a motor unit has been inundated with calcium ionophores. Assume that the membrane of the effector neuron has an action potential traveling down the membrane to the axon terminals of the neuromuscular junctions. Describe the activity of the motor unit with the embedded calcium ionophores, comparing it to a normal response of the motor unit in the absence of calcium ionophores.

2. Luteinizing hormone, secreted by the Anterior Pituitary Gland, is related to the secretion of estrogen in females and testosterone in males. Choose either the male or female to explain the feedback mechanism between the two appropriate hormones. On the molecular level, explain how each (leutenizing hormone and either estrogen or testosterone) might interact with its target cell to bring about a response

Solution

Luteinizing hormone is secreted by the anterior pituitary gland and then it triggers the testosterone production in testes in males.

Luteinizing hormone is controlled by another hormone that is gonadoptropin releasing hormone released from hypothalamus of the brain.

When the testosterone hormone level is low in the blood, GnRH hormone is secreted from the brain and it will stimulate the production of Luteinizing hormone and finally increase the production of testosterone hormone and vice versa.