Chapter 3

This chapter deals with the biological side of psychology. It starts the chapter by talking about genotypes and phenotypes. The genotype is your genetic make up and the phenotype is how you look physically. Next it talks about twins there are two different types monozygotic and dizygotic. Monozygotic twins form from the same egg and result in what we call identical twins. Dizygotic form from two eggs and result in non identical twins. We can use twins to study how biology plays a role in psychology by studying the similarities in the monozygotic compared to those in the dizygotic. There are three different types of neurons sensor, motor, and inter. Sensory gets information from outside the body. Motor neurons are in charge of telling the muscles to contract or to relax. Interneurons are used to comunicate over a short circuits. Dendrites are short branching appendeges that are used to increase the neurons receptive field and detect chemical signals. Axons are outgrowths that the information travels down to other neurons. Resting membrane potential happens when the inside of a neuron is more negative than the outside creating the electrical ability to fire. When the cell fires sodium gates open and potasium goes out because of the increases of sodium. This causes the inside to become more positive and the neuron fires. Neurotransmitters comunicate with one another by sending chemical signals that bind with receptors on the next neuron. Dopamine is a monoamine neurotransmitter involved in reward, motivation, and motor control. There are four lobes of the brain the frontal, parietal, occipital, and the temporal. The frontal is in the front and it is in charge of thought, planning, and movement. the parietal is the top in the back and it is touch and spatial relations. Occipital is in the very back on the bottom and its vision. the temporal is bottom and its hearing and memory.