A&P Study Guide (Chapter 12, 13, 14) PDF

Test #4 Study Guide 1. The structure of a multipolar neuron 2. What is the definition of a mixed nerve a nerve that contains both sensory (afferent) and motor (efferent) nerve fibers, meaning it can transmit both incoming sensory information and outgoing motor signals simultaneously; *all spinal n...

Test #4 Study Guide 1. The structure of a multipolar neuron 2. What is the definition of a mixed nerve a nerve that contains both sensory (afferent) and motor (efferent) nerve fibers, meaning it can transmit both incoming sensory information and outgoing motor signals simultaneously; *all spinal nerves are considered mixed nerves 3. Electrical synapses (junctions) vs chemical synapses The major difference between a chemical and an electrical synapse is that in a chemical synapse, the nerve impulse is transmitted chemically via neurotransmitters, whereas in an electrical synapse, the nerve impulse is transmitted electrically via channel proteins (junctions). 4. The various types of glial cells in the central nervous system (CNS) and their functions as compared to the ones in the peripheral nervous system (PNS) *NEUROGLIAL CELLS: NONEXCITABLE SUPPORT(PROTECTION) CELLS FOUND IN CNS & PNS; THEY DON’T CREATE ACTION POTENTIALS OR HAVE CHEMICAL SYNAPSES* 5. True, Saltatory conduction and myelin increase the speed of nerve conduction; Saltatory conduction which is enabled by the presence of myelin on an axon, it significantly increases the speed of nerve conduction by allowing action potentials to "jump" between the gaps in the myelin sheath called nodes of Ranvier, resulting in faster signal transmission along the nerve fiber. 6. White matter is white because it is mainly dominated by myelinated axons 7. The PNS has a greater capacity to regenerate than the CNS True, the Peripheral Nervous System (PNS) has a significantly greater ability to regenerate compared to the Central Nervous System (CNS), meaning that damaged nerves in the PNS can repair themselves much better than those in the brain and spinal cord. This is true because the PNS contain Schwann cells that actively support nerve regeneration by creating a conducive environment for axon growth after injury, while the CNS lacks this type of cell. 8. The three connective tissue layers of nerves *endoneurium (innermost), perineurium (middle), and epineurium (outermost) 9. The three layers of the meninges Dura mater, arachnoid mater, pia mater (this listed in order from superior to inferior) 10.The events in neurotransmitter release from synaptic knobs Synapse: communication between neurons; the gaps between the end of an axon of one neuron and the dendrite of another.  11.The lobes of the cerebrum and their functions 12.The falx cerebri, tentorium cerebelli, and falx cerebelli are all folds of the dura mater, a tough membrane that covers the brain, acting as partitions that separate distinct parts of the brain within the skull and handle separating the following: Falx cerebri: separates the two cerebrum hemispheres and is located in the longitudinal fissure. The partition is sickle shaped. Tentorium cerebelli: separates the cerebrum from the cerebellum. The partition is shaped like a tent. Falx cerebelli: Divides the cerebellar hemispheres and partition is small and sickle like. 13.The ventricles of the brain and where they are located; how cerebrospinal fluid (CSF) is made and how it is reabsorbed back into the venous circulation Lateral Ventricle, Third Ventricle, & 4th Ventricle:  CSF is produced by the ependymal cells in the choroid plexus 14.Gyri, sulci, and fissures (definition) Gyri: elevated ridges of the cerebrum Sulci (sn), Sulcus (pl): grooves or depressions of the cerebrum Fissure: a deep groove that separates large regions of the brain 15.The corpus callosum acts as a bridge connecting the left and right hemispheres of the brain, allowing them to communicate and transfer information between each other, enabling coordinated functions like sensory perception, motor control, and cognitive processing across the brain 16.The left side of the brain controls the right side of the body. This statement is true due to the contralateral organization of the brain at the medulla oblongata where nerves tend to crossover from right and left. 17.What do the association areas of the brain do Association areas are regions of the cerebral cortex that do not have a specific sensory or motor function. Instead, they integrate and interpret information from various sources to enable higher cognitive processes such as memory, learning, and decision- making. 18.The cerebral hemisphere for speech is located on the left side of the brain for all right-handed people and half the left-handed people This is true due to cerebral lateralization. Which refers to the refers to the specialization of functions between the two hemispheres of the brain, where certain cognitive processes are predominantly controlled by either the left or right side; essentially meaning each side of the brain has unique functions assigned to it. Corpus callosum connection: The two hemispheres communicate with each other through the corpus callosum, which tends to be thicker in women and this is why they are better at multitasking than men. Left hemisphere dominance: Typically, the left hemisphere is more involved with language skills like speaking, writing, and understanding words. Right hemisphere dominance: The right hemisphere is often associated with spatial perception, facial recognition, and emotional processing 19. True, the pineal gland produces melatonin, a hormone that helps regulate the sleep wake cycle. 20.What is the function of the thalamus The Thalamus is your body's information relay station. All information from your body's senses (except smell) must be processed through your thalamus before being sent to your brain's cerebral cortex for interpretation. Your thalamus also plays a role in sleep, wakefulness, consciousness, learning and memory. 21.The structure of the cerebellum and it’s function The cerebellum aka “the little brain” is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor control. It is constructed as the following: Cerebellar cortex: the outer gray outer layer of the cerebellum Vermis: connects the cerebellar hemispheres Cerebellar hemisphere: the two regions of cerebellum on either side of vermis Arbor vitae: the white tree like lines of myelinated nerve fibers Folia: elevated ridges of the cerebellum 22.What does the limbic system do and what is the role of the hippocampus in memory  The limbic system consists of five nuclei, which are the amygdala, hippocampus, thalamus, hypothalamus, and cingulate gyrus. This system is responsible for coordinating and processing emotions, memories and arousal. It is also involved in the perception of smells. 23.The cranial nerve that goes to most organs in the body is CN X Vagus. The vagus contains both motor and sensory nerves and is apart of the automatic nervous system which controls involuntary functions. (ex: breathing and digestion) *INSERT A PICTURE OF VAGUS* 24.The cranial nerve that controls the muscles of facial expression is CN XII the facial nerve. Which is responsible for controlling the muscles used for smiling, frowning, raising eyebrows, and wrinkling the nose. It also aids in other functions such as: tasting food, tear production, and sensation from the ears (hearing). 25. Anatomy of the Spinal Cord: The conus medullaris (T12 and below), cauda equina, filum terminale, denticulate ligaments, gray commissure, central canal, and the fact that the spinal cord ends at L1 Grey Commissure: Central Canal: 26.True, the longest and largest nerve in the body is the sciatic nerve which is part of the sacral nerve plexus. It originates from the lower lumbar and sacral nerve roots and extends through the leg. This plays a crucial role in both motor and sensory functions in the lower limb. 27.What are reflexes and what is the order of events in a reflex arc  Reflex: A rapid, preprogrammed involuntary response of muscles or glands to a stimulus. The order of events of a reflex is as followed: receptor detects stimulus → sensory neuron transmits signal to spinal cord → interneuron in spinal cord relays signal to motor neuron → motor neuron sends signal to effector (muscle) causing a response Extra Notes: Plexuses: an intertwining of nerves