BIO 3200 Chapter 9 not lili

What part of the neural tube gives rise to the ventricles?

Lumen of the neural tube

Which part of the brain develops first?

Midbrain

Approximately how much CSF is generated by all of the choroid plexuses each day?

340 mL

How much does the fact that the brain is floating in CSF reduce the effective weight of the brain?

25 fold

What must be the approximate ionic concentrations in the CSF?

Low [K+], High [Na+]

A sample of fluid from which compartment would give you the best indication as to the chemical environment of the brain?

Subarachnoid space

What types of molecules would be able to freely pass through the BBB despite the presence of tight junctions?

Lipophilic molecules

What brain region that we've already discussed would need a leaky BBB to function properly?

Hypothalamus

Based on the organization of the gray matter, what direction would the green white matter tracts carry information?

Ascending

What part of the pituitary has a neural origin?

Posterior pituitary

What is the outer layer of the cerebrum composed of?

Neuronal cell bodies

What part of the brain is the reticular formation a part of?

Brain stem

What is the neurotransmitter for the noradrenergic system?

Norepinephrine

What kind of neurotransmitter is dopamine?

Amine

What does the amplitude of waves during slow wave sleep tell you about the coordination of neuronal firing?

It is highly coordinated

What part of the brain is the pineal gland a part of?

Diencephalon

What hormone is released by the pineal gland?

Melatonin

What brain regions are most important for regulating emotions?

Limbic system

What is the ability of human brains to change circuit connections and function in response to sensory input and past experience?

Plasticity

What type of behaviors are related to feeling and emotion?

Affective behaviors

What type of behaviors are related to thinking?

Cognitive behaviors

Which part of the brain is responsible for human reasoning and cognition?

Cerebrum

What structures protect the central nervous system in vertebrates?

Skull and vertebral column

What are the meninges, starting from the layer next to the bones?

Dura mater, arachnoid membrane, pia mater

What are the purposes of cerebrospinal fluid (CSF)?

Buoyancy, cushioning, chemical protection

Where is cerebrospinal fluid (CSF) made?

Choroid plexus

How does the concentration of H+, Na+, and K+ in CSF compare to blood plasma?

H+ is higher, Na+ is the same, K+ is lower in CSF

What is the only fuel source for neurons under normal circumstances?

Glucose

What is termed when there is a low concentration of glucose in the blood?

Hypoglycemia

What do neurons consume large quantities of to synthesize ATP?

Oxygen

What percentage of the blood pumped by the heart goes to the brain?

15%

What is the blood-brain barrier?

Capillaries that are less leaky due to tight junctions between endothelial cells

What is the function of the blood-brain barrier?

Regulate substances allowed into brain tissue

How are gray matter and white matter different anatomically?

Gray matter contains nerve cell bodies; white matter contains myelinated axons

What areas of the cerebral cortex are responsible for perception, movement, and voluntary behavior?

Sensory areas, motor cortex, association areas

What does cerebral lateralization refer to?

Asymmetrical distribution of function between the two lobes of the cerebrum

What functions are centered in the left and right brain?

Left brain: language; right brain: spatial skills

What are the two major phases of sleep?

REM sleep and slow-wave (deep) sleep

What is the role of the amygdala in the limbic system?

Center for basic instincts and learned emotional states

What are the broad categories of learning?

Associative and nonassociative

What is habituation?

A person responds less to a repeated stimulus

What is sensitization?

An enhanced response to a dangerous or unpleasant stimulus

What anatomical structure is important in both learning and memory?

Hippocampus

Which two centers of the cortex are involved in integrating spoken language?

Broca's area and Wernicke's area

What is the pathway that cerebrospinal fluid follows through the nervous system?

Secreted into the ventricles, flows into the subarachnoid space, reabsorbed by the cerebral arachnoid membrane

What are the three brain systems that regulate motor output by the CNS?

Sensory system, behavioral state system, cognitive system

What is the role of Wernicke's area in language?

Understand language

What is the role of Broca's area in language?

Produce language

What is the function of the reticular formation?

Arousal and sleep, muscle tone, breathing, blood pressure, and pain.

What does the reticular activating system do?

Helps maintain consciousness.

What is the role of the limbic system?

Links higher cognitive functions with primitive emotions such as fear.

What happens to short-term memory without consolidation?

It disappears.

What is long-term memory?

Stored for recall and includes reflexive (unconscious) and declarative (conscious) memory.

What are nuclei in the CNS?

Clusters of nerve cell bodies.

What are ganglia?

Clusters of nerve cell bodies outside the CNS.

What are tracts?

Bundles of axons within the CNS.

What are nerves?

Bundles of axons outside the CNS.

What are horns in the spinal cord?

Extensions of spinal cord gray matter that connect to peripheral nerves.

What are nerve fibers?

Bundles of axons.

What are roots in the nervous system?

Branches of peripheral nerves that enter or exit the spinal cord.

What is expressive aphasia?

The ability to understand but not communicate in a coherent manner.

How did Mr. Andersen's therapy help him?

Singing allowed him to communicate by integrating information from Wernicke's area.

What was the outcome of the seat belt study?

Learning occurred, but it did not translate into behavioral responses.

What did Henri Pieron's study on sleep-deprived dogs suggest?

Sleep-deprived dogs produce a substance that induces sleep.

What controls should Pieron have included in his study?

CSF from normal dogs into sleep-deprived dogs, CSF from normal dogs into normal dogs, and CSF from sleep-deprived dogs into other sleep-deprived dogs.

What did the 2002 study on hormone replacement therapy and Alzheimer's find?

Women who used hormone replacement therapy had a lower incidence of Alzheimer's.

What factors should be considered in the hormone replacement therapy study?

Genetics, age, general health, ethnicity, and geographical location.

Why did the young woman experience seizures after taking Ecstasy?

Low plasma osmolality caused water to move into cells, leading to brain swelling and increased pressure inside the skull.

What are neurons?

Cells that link together to form circuits, allowing them to perform different functions.

What do the circuits formed by neurons give rise to?

Emergent properties such as thinking and feeling.

Why are flatworms and earthworms good subjects for studying the nervous system?

They have very large neurons and can be transparent.

How does the nervous system develop in vertebrates?

The nervous system develops closer to the brain.

What does the CNS consist of in vertebrates?

A layer of neural tissue surrounded by fluid-filled central cavity.

What happens on Day 20 of nervous system development?

Neural plate cells migrate toward the midline, and neural crest cells migrate with them.

What forms on Day 23 of nervous system development?

The neural tube formation is almost complete; neural crest cells become the PNS.

What does the neural tube become?

The CNS (central nervous system).

What are the two divisions of neural tissue?

Gray matter and white matter.

What does gray matter consist of?

Mostly cell bodies and unmyelinated axons.

What does white matter consist of?

Myelinated axons.

What are the three layers of the meninges?

Dura mater, arachnoid membrane, and pia mater.

What is the subarachnoid space?

The space between the pia mater and arachnoid membrane where cerebrospinal fluid (CSF) is present.

What is the function of the choroid plexus?

To produce cerebrospinal fluid (CSF).

How much CSF is produced by the choroid plexus in an adult brain?

Approximately 340 ml per day.

What is the blood-brain barrier (BBB)?

A barrier that helps prevent toxins from entering the brain.

What is the role of tight junctions in brain capillaries?

They prevent the free flow of solutes from the blood to the brain.

What is the major pathway for information flow from the brain to the rest of the body?

The spinal cord.

What do dorsal root ganglions receive?

Sensory information.

What is the function of the ventral root?

It is important for motor commands that go to the body.

What does the medulla oblongata serve as?

A transition between the spinal cord and the brain.

What percentage of tracts that go through the medulla cross the midline?

90%.

What role do neurons play in involuntary functions?

They control functions like blood pressure, breathing, swallowing, and vomiting.

What is the function of the pons?

Acts as a relay station between the cerebrum and cerebellum, and contains neurons important for regulating breathing.

What does the midbrain serve as a relay for?

Auditory and visual reflexes, and helps control eye movement.

How many cranial nerves originate from the brain stem?

11 out of 12 cranial nerves originate from the brain stem; the olfactory nerve is the exception.

What is the reticular formation responsible for?

Controls wakefulness, sleep, muscle tone, and regulation of pain.

What does the term 'diencephalon' mean?

'Between brain'; it is located between the cerebrum and brainstem.

What are the four parts of the diencephalon?

Thalamus, hypothalamus, pineal gland, and pituitary gland.

What is the function of the thalamus?

Acts as a relay station for sensory information.

What is the role of the hypothalamus?

Regulates homeostasis, including body temperature, reproduction, and food intake.

What is the largest part of the brain?

The cerebrum.