Nervous System And Brain Flashcards
What are the three layers of the meninges?
Dura mater, Arachnoid mater, Pia mater
What is the function of the dura mater?
Outermost tough membrane covering neural tissue
How many layers does the dura mater have?
Two layers
What are the two layers of the dura mater?
Outer Periosteal layer, Inner Meningeal layer
What 3 supportive structures are formed by the dura mater?
Falx cerebri, Falx cerebelli, Tentorium cerebelli
What does the falx cerebri do?
Divides the brain into left and right hemispheres
What does the falx cerebelli do?
Divides the brain into left and right cerebellar hemispheres
What is the role of the tentorium cerebelli?
Separates the cerebellum from the cerebrum
What type of layer is the arachnoid mater?
Filamentous layer
What is the pia mater?
Thin vascular layer adhering to the contours of the brain
What fills all meningeal spaces?
All spaces are filled with cerebrospinal fluid.
Where is the epidural space located?
Between the brain and the skull (dura mater + bone).
What is the subdural space?
The space between the dura mater and arachnoid mater.
Where is the subarachnoid space found?
Between the arachnoid and pia mater.
What is cerebrospinal fluid?
A clear liquid similar to blood plasma.
Where does cerebrospinal fluid fill?
It fills ventricles, canals, and the subarachnoid space.
What are the functions of cerebrospinal fluid?
- Buoyancy (Support weight)
- Protection
- Chemical stability, removes waste.
What is the function of the choroid plexus
Made of ependymal cells and secrete and circulate cerebral spinal fluid
Where does CSF flow begin?
Choroid Plexus in lateral Ventricles
What connects the lateral ventricles to the third ventricle?
Interventricular foramen
What connects the third ventricle to the fourth ventricle?
Cerebral aqueduct
Where does the fourth ventricle feed into
Central Canal / Subarachnoid space
What regulates the Blood-Brain Barrier?
The Blood-Brain Barrier is tightly joined and highly regulated by Astrocytes.
What types of molecules are permeable through the Blood-Brain Barrier?
Lipid soluble molecules (such as alcohol, nicotine, and anesthetics)
Small molecules (gases and glucose)
What types of molecules are impermeable to the Blood-Brain Barrier?
Large molecules such as proteins and antibiotics are impermeable.
What is the location of the Medulla Oblongata?
Anterior ventral to the 4th ventricle and cerebellum, superior to the spinal cord, inferior to the pons.
What types of tracts are found in the Medulla Oblongata?
Ascending and descending tracts.
What vital reflexes are controlled by the Medulla Oblongata?
Cardiac function, breathing, and vasomotor control (blood vessel diameter)
What system does the Medulla Oblongata contain part of?
The Reticular Activating System (RAS).
What is the function of the reticular activating system (RAS)?
Regulate sleep and waking up (conscious attention)
What is the function of the reticular activating system (RAS)?
Regulate sleep and waking up (conscious attention)
What is the location of the Pons?
Interior to the 4th ventricle and cerebellum, superior to the medulla, and inferior to the midbrain.
What is the function of the Pons?
Connection pathway between the cerebellum and cerebrum.
What is the location of the Midbrain?
Anterior to the 4th ventricle, anterior to the cerebellum, and superior to the pons.
What are the components of the Midbrain?
Cerebral Peduncles and Corpora Quadrigemina.
Function of cerebral peduncles
Voluntary motor fibers pass through here to skeletal muscle.
Function of corpora quadrigemina and its 2 parts
Superior colliculi (visual reflexes)
Inferior colliculi (auditory reflexes)
What is the Diencephalon?
The Diencephalon is a part of the brain that includes structures such as the thalamus and hypothalamus.
Where is the Thalamus located?
The Thalamus is located deep in the cerebrum, superior to the hypothalamus, surrounding the third ventricle.
What is the function of the Thalamus?
Nearly all sensory information travels through the Thalamus to the cerebral cortex, except for smell.
Where is the Hypothalamus located?
The Hypothalamus is located deep in the cerebrum, superior to the thalamus, surrounding the third ventricle.
What does the Hypothalamus control?
The Hypothalamus controls the Autonomic Nervous System (ANS), including sympathetic and parasympathetic responses, as well as the endocrine system.
What hormones does the Hypothalamus secrete?
The Hypothalamus secretes Antidiuretic Hormone (ADH) and Oxytocin.
What is the function of Antidiuretic Hormone (ADH)?
ADH helps retain water in the body.
What is the function of Oxytocin?
Oxytocin is involved in labor contractions.
What is the function of the pineal gland
Produce melatonin
What is the primary function of the Nervous System?
Works to maintain homeostasis
The Nervous System is the master controlling and communicating system of the body.
What are the three overlapping functions of the Nervous System?
- Sensory input: Detects internal and external changes.
- Integration: Processes and interprets information.
- Motor Output: Activates effector organs to produce a response.
What are the two principal parts of the Nervous System?
- Central Nervous System (CNS): Comprises the brain and spinal cord, serving as the integration and control center.
- Peripheral Nervous System (PNS): Comprises nerves that branch off the brain and spinal cord.
What are the components of the Peripheral Nervous System (PNS)?
The PNS includes spinal nerves (to and from the spinal cord) and cranial nerves (to and from the brain).
What is a ganglion?
A ganglion is a swelling of cell bodies.
What is the role of sensory neurons?
Sensory (afferent) neurons detect changes in the body or external environment and transmit information away from receptors into the brain or spinal cord.
What is the function of interneurons?
Interneurons (association neurons) lie between sensory and motor pathways in the CNS, processing, storing, and retrieving information.
What do motor (efferent) neurons do?
Motor (efferent) neurons send signals out to muscles and gland cells, which carry out responses called effectors.
What are the divisions of the Peripheral Nervous System?
The Peripheral Nervous System has two divisions: Afferent Division (Sensory) and Efferent Division (Motor).
What does the Afferent Division (Sensory) do?
The Afferent Division conveys impulses to the CNS, including somatic sensory info from the skin and visceral info from internal organs.
What does the Efferent Division (Motor) do?
The Efferent Division conveys impulses away from the CNS, including somatic signals to skeletal muscles and visceral signals through the autonomic nervous system.
What are the two branches of the autonomic nervous system?
The autonomic nervous system has two branches: Parasympathetic and Sympathetic.
What are the properties of neurons?
excitability (responding to changes),
conductivity (producing traveling electrical signals),
secretion (releasing neurotransmitters when an electrical signal reaches the end of a nerve causes secretion
Define nuclei
Cluster of cell bodies in CNS
Define ganglia
Cluster of cell bodies and PNS
Define Tracts
Bundles of neuron processes in CNS
Define nerves
Bundles of neuron processes in PNS
What is a neuron process and what are the two types
An arm process that extends from the cell body.
Dendrites and axons
Explain axons vs dendrites
Axons Send or transmit info to the next cell
Dendrites receive information and transmit it to the cell body
Explain axons
Send or transmit info to the next cell
Define axon collaterals and axon terminals, and axon hillock
Axon collateral- axon with branches
Axon terminals- distal ends
Axon hillock- where nerve transmission action potential starts
Define axon collaterals and axon terminals, and axon hillock
Axon collateral- axon with branches
Axon terminals- distal ends
Axon hillock- where nerve transmission action potential starts