Terms : Hide Images
| 6636321664 | neuron | a nerve cell; the basic building block of the nervous system | 0 | |
| 6636321665 | dendrite | the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body | 1 | |
| 6636321666 | axon | the extensions of a neuron, ending in branching terminals fibers, through which messages pass to other neurons | 2 | |
| 6636321667 | myelin sheath | a layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses | 3 | |
| 6636321668 | action potential | a neural impulse; a brief electrical charge that travels down an axon | 4 | |
| 6636321669 | threshold | the level of stimulation required to trigger a neural impulse | 5 | |
| 6636321670 | synapse | the junction between the axon tip of the sending neuron and the dendrite of the receiving cell. The tiny gap at this junction if called the synaptic gap or synaptic cleft. | 6 | |
| 6636321671 | neurotransmitters | chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, these travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse | 7 | |
| 6636321672 | reuptake | a neurotransmitter's reabsorption by the sending neuron | 8 | |
| 6636321673 | endorphins | "morphine within" -- natural, opiatelike neurotransmitters linked to pain control and pleasure | 9 | |
| 6636321674 | central nervous system | the brain and spinal cord | 10 | |
| 6636321675 | peripheral nervous system | the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body | 11 | |
| 6636321676 | nerves | bundles of axons the form neural "cables" connecting the central nervous system with muscles, glands, and sense organs | 12 | |
| 6636321677 | somatic nervous system | the division of the peripheral nervous system that controls the body's skeletal muscles | 13 | |
| 6636321678 | autonomic nervous system | the part of the peripheral nervous system that controls the glands and muscles of the internal organs (such as the heart) | 14 | |
| 6636321679 | sympathetic nervous system | the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations | 15 | |
| 6636321680 | parasympathetic nervous system | the division of the autonomic nervous system that calms the body, conserving its energy | 16 | |
| 6636321681 | reflex | a simple, automatic response to a sensory stimulus, such as the knee-jerk response | 17 | |
| 6636321682 | endocrine system | the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream | 18 | |
| 6636321683 | hormones | chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream and affect other tissues | 19 | |
| 6636321684 | adrenal glands | a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress | 20 | |
| 6636321685 | pituitary gland | the endocrine system's most influential gland; under the influence of the hypothalamus, this regulates growth and controls other endocrine glands | 21 | |
| 6636321687 | electroencephalogram (EEG) | an amplified recording of the waves of electrical activity that sweep across the brain's surface; these waves are measured by the electrodes placed on the scalp | 22 | |
| 6636321688 | CT (computed tomography) scan | a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body | 23 | |
| 6636321689 | PET scan (position emission tomography) | a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a task | 24 | |
| 6636321690 | MRI (magnetic resonance imaging) | a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue; shows brain anatomy | 25 | |
| 6636321691 | fMRI (functional MRI) | a technique for revealing bloodflow and therefore, brain activity by comparing successive MRI scans; shows brain activity and structure | 26 | |
| 6636321692 | brainstem | the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; responsible for survival functions | 27 | |
| 6636321693 | medulla oblongata | the base of the brainstem; controls heartbeat and breathing | 28 | |
| 6636321694 | reticular formation | a nerve network in the brainstem that plays an important role in controlling arousal | 29 | |
| 6636321695 | thalamus | the brain's sensory switchboard; it directs messages to the sensory receiving areas in the cortex | 30 | |
| 6636321696 | cerebellum | the "little brain" at the rear of the brainstem; coordinates movement and balance | 31 | |
| 6636321697 | limbic system | doughnut-shaped neural system (including the hippocampus, amygdala, and hypothalamus) associated with emotions and drives | 32 | |
| 6636321698 | amygdala | two lima bean-shaped neural clusters in the limbic system linked to emotion (fear and aggression) | 33 | |
| 6636321699 | hypothalamus | this directs maintenance activities (eating, drinking) and helps govern the endocrine system via the pituitary gland | 34 | |
| 6636321700 | cerebral cortex | the intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center | 35 | |
| 6636321701 | glial cells (glia) | cells in the nervous system that support, nourish, and protect neurons | 36 | |
| 6636321702 | frontal lobe | portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscles movements and in making plans and judgment | 37 | |
| 6636321703 | parietal lobe | portion of the cerebral cortex lying at the top of the head; receives sensory input for touch and body position | 38 | |
| 6636321704 | occipital lobe | portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields | 39 | |
| 6636321705 | temporal lobes | portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information from the opposite ear | 40 | |
| 6636321706 | motor cortex | an area at the read of the frontal lobes that controls voluntary movements | 41 | |
| 6636321707 | somatosensory cortex | area at the front of the parietal lobes that registers and processes body touch and movement sensations | 42 | |
| 6636321708 | association areas | areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking | 43 | |
| 6636321709 | aphasia | impairment of language, usually caused by left hemisphere damage either to Broca's or Wernicke's area | 44 | |
| 6636321710 | Broca's area | control language expression -- an area in the left frontal lobe that directs the muscle movements involved with speech | 45 | |
| 6636321711 | Wernicke's area | control's language reception -- a brain area in the left temporal lobe involved in language comprehension and expression | 46 | |
| 6636321712 | Broca's aphasia | a language impairment in which the person has difficulty with the motor functions of speech and only uses nouns and verbs | 47 | |
| 6636321713 | Wernicke's aphasia | a language impairment in which the person has difficulty with language comprehension, often speaks in long, complicated sentences that have no meaning | 48 | |
| 6636321714 | plasticity | the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience | 49 | |
| 6636321715 | corpus callosum | the large band of neural fibers connecting the two brain hemispheres and carrying messages between them | 50 | |
| 6636321717 | left hemisphere | region of the brain the controls the right side of the body, logic, math, science, and language | 51 | |
| 6636321718 | right hemisphere | region of the brain the controls the left side of the body, art, creativity, spatial skills, recognizing faces | 52 | |
| 6636321719 | sensory neuron | neurons that carry incoming information from sensory organs to the brain and spinal cord | 53 | |
| 6636321720 | motor neurons | neurons the carry outgoing information from the brain and spinal cord to the muscles and glands | 54 | |
| 6636321721 | hippocampus | main memory center of the brain | 55 | |
| 7531112981 | Agonist | enhance the action of a neurotransmitter, usually by mimicking it. | 56 | |
| 7531118592 | Antagonist | inhibit the action of the neurotransmitter, usually by blocking the receptors. | 57 |
