click below
click below
Normal Size Small Size show me how
Psych Exam 2
Question | Answer |
---|---|
What are three types of cells in the body? | Receptor, Effector, Neurons |
What are receptor cells? | Cells located in sense organs that receive stimulation from the external environment |
What are effector cells? | Cells located near muscles and gland that tell muscles to contract and glands to secrete |
What are neurons? | A single nerve cell that transports or transmits messages |
What are glial cells? | Cells that are like glue. They do not send or receive nerve impulses. They hold neurons in place, but outnumber them 10 to 1. They protect the neurons by absorbing toxins and getting rid of any waste that could damage or kill the neurons. |
What are three main types of neurons? | Afferent (sensory), Interneurons (association), Efferent (motor) |
What is an afferent (sensory) neuron? | a neuron that takes the message from receptor cells into the central nervous system (takes message into the brain and spinal cord) |
What are interneurons? (association neurons)? | Neurons that connect to other neurons. They are most of the time found in the central nervous system |
What are efferent (Motor) neurons? | Neurons that bring messages from the central nervous system |
What are three main structures? | Dendrites, Soma, Axon |
What are dendrites? | short fibers that receive the message |
What is the soma? | The cell body, where the nucleus is found. It takes care of functions of cell so cell can survive |
What are axons? | Long fibers |
What is the myelin Sheath? | A fatty white substance/tissue that surrounds the axon. It speeds up neural impulse. Degeneration can lead to MS |
What are nodes of ranvier? | Breaks in the myelin sheath |
What is the axonal terminal? | It is the axon splitting and branching out, it breaks and communicates with other neurons |
What are terminal buttons? | They house the synaptic vesicles |
What is the synaptic cleft? | The space between two neurons |
What are neural networks? | Neurons that operate together to perform complex functions |
What are receptors? | Sites on the surface of a cell that allow only one type of neurotransmitter to fit into them, triggering a chemical response that may lead to an action potential |
What is a neural impulse? | Neurons transport (transmit) messages, Neurons do not physically touch, Neural Impulse is the communication |
What does electrochemical mean? | electrical and chemical |
What are ions? | electrically charged particles/atoms |
What is the resting state/potential of a neuron? | No stimulation (cell has not fired), State of readiness, Not receiving any messages, No impulse, Membrane is semi-permeable, Ions are polarized (condition of membrane/cell is polarized), Cell is more negatively charged inside than outside |
What is the action state/potential of a neuron | Cell is stimulated, Neuron has “fired”, Impulse or message, Membrane is permeable, Cell is more positively charged inside relative to outside, Condition of membrane/cell is depolarized |
What is the absolute refractory period? | Immediately following action potential, Membrane is not excitable, Cannot discharge another impulse |
What is the relative refractory period? | Immediately following the absolute refractory period, Membrane is excitable, Impulse must be stronger than the initial impulse (stimulation) |
What is the All or none law? | Action potentials occur, Either at a uniform and maximum intensity, Or they do not occur at all |
What is an excitatory Neurotransmitter? | Causes the action potential; neuron fires |
What is an inhibitory neurotransmitter? | Prevents the neuron from firing |
What is the breakdown (enzymes) deactivation? | Neurotransmitter can be broken down by other chemicals (enzymes) |
What is the reuptake deactivation? | Transmitter molecules are taken back into the presynaptic axon terminals |
What is a neurotransmitter? | Chemical messengers in nervous system, Housed in synaptic vesicles, They transmit a message across synaptic cleft |
What is Acetylcholine (Ach)? | Generally excitatory, One of the first neurotransmitters to be identified, Stimulates skeletal muscles (contract), Role in memory, Under production results in Alzheimer’s disease, Overproduction results in convulsions (black widow spider bites) |
What is Norepinephrine? | Generally excitatory, Involved in wakefulness, arousal, and mood; Underproduction results in depression, Over-production results in stress and panic |
What is Serotonin? | Affects sleep, arousal, appetite, and mood; Underproduction results in depression, sleeping and eating problems; Low levels found in suicide victims; Overproduction results in obsessive compulsive disorder (OCD) |
What is Dopamine? | Involved in emotional arousal (sensations of pleasure) and movement; Underproduction results in Parkinson’s disease and depression, Overproduction results in Schizophrenia |
What is the peripheral nervous system? | All neurons outside of the Central Nervous System, Contains all the neural structures that lie outside of the brain and spinal cord, breaks down into two parts: somatic nervous system and autonomic nervous system |
What is the Somatic Nervous System? | A system of sensory and motor neurons, sense and respond to our environment, Controls the voluntary movements of skeletal system |
What is the Autonomic Nervous system? | Smooth or visceral, A system that sense the body’s internal functions, Controls many glands and smooth muscles, Involuntary activities of your internal organs |
What is the Sympathetic Nervous System? | “fight or flight”- gets you ready for an emergency, activation or arousal function, when you are intensely aroused (during emergency situations), heart begins to pound, your breathing quickens, and you perspire |
What is the Parasympathetic Nervous System? | When emergency is over, slows down the body, maintains a state of internal equilibrium, causes the opposite of sympathetic changes |
What is Homeostasis? | A delicately balanced or steady internal state, inverse reactions |
What are the two parts of the Central Nervous System? | Spinal cord and brain |
What is the spinal cord? | Connects most parts of the peripheral nervous system with the brain, A densely packed bundle of nerve fibers, Everything going to the brain must pass through the spinal cord, Handles simple reflexes |
What are the three regions of the brain? | Hindbrain, Midbrain, Forebrain |
What is the Hindbrain? | The lowest and most primitive level of the brain |
What are the five parts of the hindbrain? | Brainstem, Medulla, Pons, Reticular Formation, Cerebellum |
What is the brainstem? | Point at which the spinal cord enters the brain, Supports vital life functions |
What is the Medulla? | Life sustaining functions, Such as heart rate, blood pressure, swallowing and respiration (breathing), Damage typically results in death or being placed on life support |
What is Pons ("bridge")? | higher and lower levels of the nervous system, role in triggering dreams, produces chemicals that help maintain the sleep-wake cycle |
What is Reticular Formation (RF)? | Reticular Activating System (RAS), Plays role in arousal and attention alerts you that messages are coming, can either block or allow those messages into your awareness, also signals importance of message, tones down during sleeping |
What can damage and abnormalities to the RF cause? | Damage—sleep-like, coma state, Abnormalities (in locus coeruleus) linked to ADHD and PTSD |
What is the Cerebellum ("little brain")? | contains more neurons than the rest of the brain, Concerned with muscular movement – coordination, learning, and memory, Regulates movements requiring precise timing, Functions are easily disrupted by alcohol |
What are examples of movements requiring precise timing? | Threading a needle, dancing, playing an instrument, surgery, athletics, etc. |
What is Ataxia? | A drunken-like state |
What is the midbrain? | Contains clusters of sensory and motor neurons, Important for hearing and sight, particularly for auditory & visual reflexes, keeps eyes focused on an object while moving head, allows you to reflexively turn your head, one place where pain is registered |
What is an example of reflexively turning your head? | when hearing the backfiring of a car |
What is the forebrain? | The brain’s most advanced portion from an evolutionary standpoint |
What is the Thalamus? | Two egg-shaped structures, Functions like a “switchboard”, Receives inputs from sensory organs, Sends to appropriate areas of the brain, Sensory relay center/station or a switchboard, Relay pain signals from spinal cord |
What is the Hypothalamus? | Plays a major role in Hunger, thirst, body temperature and sex drive; Connected to ANS – reactions to stress; Connected to endocrine system; Two parts: Lateral hypothalamus and Ventromedial Hypothalamus |
What is the Lateral Hypothalamus? | Tells you to eat and drink |
What is the Ventromedial Hypothalamus? | Tells you to stop eating and drinking, brain studies, stimulation vs. destruction (lesion) |