Central Nervous System
Peripheral Nervous System
Cranial Nerves in Action
Basic functions of Brain Structures
Anatomy of a Neuron
100
What two parts make up the central nervous system?
The spinal cord and brain.
100
What are the primary components of the peripheral nervous system (PNS), and how do they differ from those of the central nervous system (CNS)?
The peripheral nervous system (PNS) includes all nerves outside of the brain and spinal cord, consisting of 12 pairs of cranial nerves and 31 pairs of spinal nerves. It connects the CNS to sensory organs, muscles, and glands throughout the body.
100
This cranial nerve is responsible for the sense of smell.
The Olfactory nerve (CN I)
100
Which structure is the largest part of the brain and responsible for higher functions such as cognition, language, and memory.
Cerebrum
100
1. Describe the main components of a neuron as illustrated in Figure 8–25. What are the functions of the soma, dendrites, axon, and terminal segment?
The main components of a neuron include the soma (cell body), dendrites, axon, and terminal segment. The soma contains the nucleus and organelles necessary for cellular function. Dendrites receive signals from other neurons or sensory receptors. The axon conducts electrical impulses away from the soma to the terminal segment, where neurotransmitters are released to communicate with other neurons or target cells.
200
Identify the two structures that make up the central nervous system.
Letters A, B, and C
200
Describe the structure of a typical peripheral nerve. How does it differ from a nerve tract found in the central nervous system?
A typical peripheral nerve consists of bundles of axons enclosed by connective tissue layers: the endoneurium, perineurium, and epineurium. In contrast, a nerve tract in the CNS is a bundle of axons that are usually myelinated and serve to connect different regions within the CNS.
200
This cranial nerve is involved in controlling the muscles of the face, the salivary glands, and taste from the anterior two-thirds of the tongue.
The facial nerve (CN VII)
200
Damage to this brain region can lead to movement disorders characterized by involuntary muscle contractions and difficulties initiating and stopping movements.
Basal ganglia
200
Explain the role of myelin and the significance of nodes of Ranvier in neuronal function. How do these structures contribute to the speed and efficiency of signal transmission along axons?
Myelin is a fatty substance produced by oligodendrocytes in the CNS and Schwann cells in the PNS. It wraps around axons, forming a myelin sheath that insulates and speeds up electrical signal conduction. Nodes of Ranvier are gaps in the myelin sheath where action potentials are regenerated, enhancing the speed and efficiency of signal transmission along the axon.
300
Which part of the brain connects the two hemispheres?
The corpus callosum
300
How might damage to a sensory ganglion in the PNS differ in its effects compared to damage to a motor nerve in terms of symptoms and recovery?
Damage to a sensory ganglion in the PNS can result in sensory deficits such as numbness, tingling, or loss of sensation in the affected area. In contrast, damage to a motor nerve typically leads to muscle weakness or paralysis of the muscles innervated by that nerve. Recovery from sensory ganglion damage can be slower compared to motor nerve damage due to differences in the regenerative capabilities of sensory and motor neurons.
300
This cranial nerve is responsible for the movement of the tongue and can affect speech and swallowing.
The hypoglossal nerve (CN XII)
300
Which brain structure is responsible for regulating body functions such as temperature, hunger, thirst, and sexual behavior, this brain structure is vital for maintaining homeostasis?
Hypothalamus
300
How might damage to the presynaptic membrane affect synaptic transmission between neurons? Discuss potential implications for neurological disorders associated with neurotransmitter dysfunction.
Damage to the presynaptic membrane can disrupt the release of neurotransmitters into the synaptic cleft, impairing communication between neurons. This dysfunction can lead to neurological disorders such as Parkinson's disease, where dopamine release is compromised, affecting motor control and cognition.
400
If this part of the frontal lobe gets damaged, it can create some difficulty during speech production.
Broca’s area
400
Explain the concept of "dual innervation" within the autonomic nervous system (ANS) of the PNS. Provide examples of organ systems that demonstrate this phenomenon and its functional significance.
"Dual innervation" refers to the phenomenon where organs receive nerve fibers from both the sympathetic and parasympathetic divisions of the autonomic nervous system (ANS). For example, the heart receives sympathetic fibers that increase heart rate and parasympathetic fibers that decrease heart rate, allowing for precise control of organ function depending on the body's needs.
400
Which cranial nerve innervates the superior oblique muscle, allowing for downward and inward eye movement?
The Trochlear nerve (CN IV)
400
This lower part of the brainstem regulates essential functions like respiration, heartbeat, and blood pressure, as well as reflexes such as swallowing and coughing.
Medulla
400
Compare and contrast the roles of mitochondria and the endoplasmic reticulum (ER) in neuronal metabolism and function. How do these organelles support the unique energy and protein synthesis needs of neurons?
Mitochondria in neurons produce ATP, providing energy for cellular processes including neurotransmitter synthesis and axonal transport. The endoplasmic reticulum (ER) plays a role in protein synthesis, folding, and transport within the neuron, ensuring proper functioning of cellular membranes and neurotransmitter production.
500
The spinal cord is _____ in relation to the brain.
A. Dorsal
B. Caudal
C. Rostral
D. Inferior
E. Superior
F. Both B & D
G. Both C & E
Letter F, Both B & D, Caudal and Inferior
500
Discuss the role of Schwann cells in the peripheral nervous system. How do they contribute to nerve function and regeneration after injury? What molecular mechanisms are involved in this process?
Schwann cells are crucial in the PNS for myelinating axons, providing structural support, and aiding in nerve regeneration after injury. They produce factors that promote axon growth and guide regenerating axons back to their target tissues. Molecular mechanisms involved include signaling pathways like the cAMP-PKA pathway, which regulates gene expression and promotes axon growth and myelination.
500
Which cranial nerve innervates the muscles of the pharynx and larynx, and has a sensory component that carries sensation from the heart, digestive system, esophagus, and trachea?
The vagus nerve (CN X)
500
Which of the following statements accurately describe functions associated with the midbrain? Select all that apply.
A) Integrates sensorimotot functions and perception
B) Mediates sensation to the cerebral cortex
C) Maintains cortical arousal
D) Mediates auditory and visual reflexes
E) Regulates motor movements and muscle tone
C and D
500
Discuss the concept of synaptic plasticity and its relation to learning and memory. How do changes in the structure and function of synapses contribute to neural adaptations in response to experience and environmental stimuli?
Synaptic plasticity refers to the ability of synapses to strengthen or weaken over time in response to activity and experience. Long-term potentiation (LTP) and long-term depression (LTD) are mechanisms through which synapses undergo lasting changes in strength, facilitating learning and memory formation by altering synaptic efficacy and connectivity in neural circuits.