Biological Psychology: The Study of Behavior and Experience, Exams of Biological Psychology

Download Biological Psychology: The Study of Behavior and Experience and more Exams Biological Psychology in PDF only on Docsity! BIOLOGICAL PSYCHOLOGY CHAPTER ONE (KALAT) EXAM WITH CORRECTLY SOLVED ANSWERS. 1. Biological Psychology Is the study of the psychological, evolutionally, developmental mechanism of behaviors and experience; Seeks biological explanations of behaviors 2. Neurons cells that receive information and transmit it to other cells; The human brain contains approximately 100 billion individual neurons; 16 billion in Cerebral cortex, 69 billion in Cerebellum, Less than 1 billion in the rest of the brain, and 1 billion in spinal cord - their shape is distinctive compared to other 3. Santiago Ramony CaIn- the late 1800s, HE was the first to demonstrate jal (1852-1934) 4. Membrane(plasm a membrane) that the individual cells comprising the nervous system remained separate- they did not merge into each other structure that separates the inside of the cell from the outside environment; selectively permeable 5. Nucleus structure that contains the chromosomes; Cell brain 10. Sensory neuron neuron that is highly sensitive to a specific type of stimulation 11. Soma (cell body) structure containing the nucleus, ribosomes, and mi- tochondria; Responsible for the metabolic work of the neuron; Covered with synapses on its surface in many neurons 12. Dendrites Branching fibers with a surface lined with synaptic receptors responsible for bringing information into the neuron; Some also contain dendritic spines that further branch out and increase the surface area of the dendrite; The greater the surface area of the dendrite, the more information it can receive 13. Dendritic spines short outgrowths that increase the surface area available for synapses; includes of shaft and spine 14. Axon thin fiber of constant diameter; the neuron's information sender; The axon conveys an impulse toward other neurons, an organ, or a muscle; Axons can be more than a meter in length; Presynaptic terminals at the end points of an axon release chemicals to communicate with other neurons; maybe have a myelin sheath 15. Myelin sheath insulating material that covers vertebrate axon; con- tains interruptions in the sheath known as nodes of Ranvier 16. Nodes of Ranvier interruptions in the myelin sheath of vertebrate ax- ons; At each node of Ranvier, the action potential is regenerated by a chain of positively charged ions pushed along by the previous segment. 10 / 27 22. Variations among neu- rons neuron whose axons and dendrites are all confined within a given structure Neurons vary in size, shape, and function; The shape of a neuron determines it connection with other neu- 11 / 27 rons and its contribution to the nervous system; The function is closely related to the shape of a neuron - Example: Purkinje cells of the cerebellum branch extremely widely within a single plane; Bipolar neu- rons in the retina have only short branches, and some receive input from as few as two other cells. 23. Glia (neuroglia) type of cell in the nervous system that, in contrast to neurons, does not conduct impulses over long distances; "glue"; non-neuronal cells ; maintain homeostasis, form myelin, and provide support and protection for neurons in the CNS and PNS 24. Astrocytes star-shaped glia that synchronize the activity of the axons by wrapping around the presynaptic terminal and taking up chemicals released by the axon; If a few of associated axons are active at once, the astrocyte absorbs some of the chemicals they release and then temporarily inhibits all the axons 25. Microglia cells that remove waste material (dead cells and weak synapses...) and other microorganisms such as viruses and fungi from the nervous system 12 / 27 26. Oligodendrocytes glia cells that build myelin sheaths (In the CNS) 27. Schwann cells (In the PNS) glia cells that build myelin sheaths SCN (Suprachiasmatic nucleus) 28. Radial glia cells that guide the migration of neurons and the growth of axons and dendrites during embryological development 29. Blood-brain barrier A mechanism that surrounds the brain and blocks 15 / 27 oxygen; Although neurons require glucose, glucose shortage is rarely a problem, except during starvation; A more likely problem is an inability to use glucose; the human brain constitutes 2% of the body's weight, but it uses about 20% of its oxygen and 25% of its glucose 35. Thiamine vitamin, necessary to use glucose 36. Korsakoff's syndrom Prolonged thiamine deficiency, common in chronic alcoholism, leads to death of neurons and a condition called Korsakoff's syndrome, marked by severe memory impairments. 37. Nerve impulse - The electrical message that is transmitted down the axon of a neuron; Does not travel directly down the axon, but is regenerated at points along the axon so that it is not weakened - The speed of this ranges from less than 1 meter/second to 100 meters/second - The brain is not set up to register small differences in the time of arrival of touch messages - However, in vision, movements must be detected as accurately as possible - The properties of impulse conduction are well adapted to the exact needs for information transfer in the nervous system 38. Electrical gradient (polarization) difference in electrical charges between the inside and outside of the cell (membrane); tends to pull potassium and sodium ions into the cell 16 / 27 39. Resting potential condition of a neuron's membrane when it has not been stimulated or inhibited; Inside = slightly negative (-70mv) - refers to the state of the neuron prior to the sending of a nerve impulse 40. Methods for recording activity of a neuron 41. The membrane of a neuron Researchers measure the resting potential by inserting a very thin microelectrode into the cell body; The diameter of the electrode must be small enough to enter without damaging the cell. The most common electrode is a fine glass tube filled with a salt solution, tapering to a tip diameter of 0.0005 mm or less. A reference electrode outside the cell completes the circuit Contains phospholipid molecules and protein molecules 42. Selective permeability ability of some chemicals to pass more freely than 17 / 27 others through a membrane; Sodium, potassium, 20 / 27 - Studies of mammalian axons show that there is much variation in the types of protein channels and therefore in the characteristics of the action potentials 21 / 27 50. quickly closed After an action potential occurs, sodium channels are 51. the opening of potas- sium channels; Potas- sium ions flow out due to the concentra- tion gradient and take with them their posi- tive charge 52. restores the original distribution of ions (takes time); An un- usually rapid series of action potentials can lead to a buildup of sodium within the axon- Can be toxic to a cell, but only in rare instances such as stroke and after the use of certain drugs The neuron is returned to its resting state by The sodium-potassium pump later 53. Three principles 1. At the start, sodium ions are mostly outside the neuron, and potassium ions are mostly inside. 2.When the membrane is depolarized, sodium and potassium channels in the membrane open. 3.At the peak of the action potential, the sodium channels close. 54. Voltage-gated chan- nels 55. Local anesthetic 22 / 27 membrane channel whose permeability to sodium (or some other ion) depends on the voltage difference across the membrane 25 / 27 63. Local neurons Have short axons, exchange information with only close neighbors, and do not produce action potentials; When stimulated, produce graded potentials; Difficult to study due to their small size; Most of our knowledge has come from the study of large neurons 64. Graded potential a membrane potential that varies in magnitude in proportion to the intensity of the stimulus; do not follow the all-or- none law; Depolarize or hyperpolarize in proportion to the stimulation 65. Na+ channels open, Na+ begins to enter cell 66. K+ channels open, K+ begins to leave cell Step 1 of the action potential Step 2 of the action potential 26 / 27 67. Step 3 of the action potential 27 / 27 68. K+ continues to leave cell, causes mem- brane potential to re- turn to resting level 69. K+ channels close, Na+ channels reset 70. Extra K+ outside dif- fuses away Step 4 of the action potential Step 5 of the action potential Step 6 of the action potential 71. Axon hillock In a motor neuron, the action potential begins at the axon hillock (a swelling where the axon exits the soma) Na+ channels become refractory, no more Na+ enter cells