Hormones and Hormone Disruptors in the Environment Lecture Pix

Insect Hormonal System: Some pesticides work by interfering with hormonal systems, causing either accelerated or delayed development.

How neurotoxic pesticides work. Under normal conditions a stimulated presynaptic cell (left) releases neurotransmitters from vesicles (). The transmitters() float across the synaptic cleft (gap) and join with receptors on the postsynaptic cell (). This excites the postsynaptic cell () and the postsynaptic cell produces an action potential.

After the postsynaptic cell releases the neurotransmitters, they are reabsorbed by the presynaptic cell. Many antidepressants, such as Prozac, work at this level. Serotonin uptake inhibitors raise serotonin (a neurotransmitter) levels in the brain by interfering with the re-absorption. Serotonin levels then increase and the depression lifts.

Cartoon depicting the movement of an action potential down an axon, release of neurotransmitters from vesicles, neurotransmitters hitching up to receptors on the postsynaptic cell, then depolarization of the postsynaptic cell and recycling of neurotransmitter by the presynaptic cell.

Pesticides such as malathion work as acetylcholinessterase inhibitors.

Early Embryology of Sexual Development is under the control of testosterone

General Structure of a Sheep Brain

White matter tracts inside the brain serves as a high-speed network to bypass surface grey matter.

Distribution of White and Grey Matter in the Brain

The Corpus Callosum

Presumptive male	Presumptive female

Fetal Alcohol Syndrome (FAS) Note very small corpus callosum.

Hypothalamus- Differences in Neuron Density and other male-female differences