Chapter 3
Biological Foundations of Psychology
By Boundless
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Neurons are specialized cells that transmit chemical and electrical signals to facilitate communication between the brain and the body.
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Neural impulses occur when a stimulus depolarizes a cell membrane, prompting an action potential which sends an "all or nothing" signal.
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The synapse is the site at which a chemical or electrical exchange occurs between the presynaptic and postsynaptic cells.
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Neurotransmitters are chemicals that transmit signals from a neuron across a synapse to a target cell.
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Neural networks consist of a series of interconnected neurons, and serve as the interface for neurons to communicate with each other.
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The mental processes and behaviors studied by psychology are directly controlled by the brain, one of the most complex systems in nature.
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The brain's lower-level structures consist of the brain stem, the spinal cord, and the cerebellum.
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The cerebral cortex is the outermost layered structure of the brain and controls higher brain functions such as information processing.
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The brain is divided into two hemispheres and four lobes, each of which specializes in a different function.
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The limbic system combines higher mental functions and primitive emotion into one system.
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Neuroplasticity is the brain's ability to create new neural pathways to account for learning and acquisition of new experiences.
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The nervous system controls bodily function by gathering sensory input, integrating that information internally, and communicating proper motor output.
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The central nervous system is made up of the brain and spinal cord, which process sensory input and provide instructions to the body.
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The peripheral nervous system connects the central nervous system to environmental stimuli to gather sensory input and create motor output.
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The endocrine and nervous systems work together to act as a communication system for the human body.
The hypothalamic-pituitary-adrenal axis regulates stress in vertebrates.
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Hunger is divided into long-term and short-term regulation, each stimulating different hormone responses from the hypothalamus.
Chromosomes contain genetic material that can determine a person's characteristics.
Genetic expression can be influenced by various social factors, as well as environmental factors, from light and temperature to exposure to chemicals.
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Genetic makeup has a large role in determining human behavior.
Behavior can influence genetic expression in humans and animals by activating or deactivating genes.