Unit 3 Flashcards
(25 cards)
Match each of the three germ layers with the tissues they become during development.
Ecotoderm, Mesoderm, Endoderm
[Muscles and bone/nervous system and skin/internal organs]
Ectoderm = nervous system & skin
Mesoderm = Muscles and bone
Endoderm = internal organs
What is the neural tube?
The neural tube is the embryonic structure that ultimately forms the brain, spinal cord, spine and skull. The neural tube is formed during a process called neurulation.
When discussing groups of cells, what is the difference between a nucleus and a ganglion?
the term nucleus can also refer to a group of cell bodies within the CNS.
A ganglion is the term used for a similar group of cell bodies when they are in the PNS
Explain how a problem with neural tube development can lead to a congenital defect. Please use a specific example for the neural tube problem and its associated defect.
When neural tube development towards the rostral side becomes disrupted, congential defects like ancephaly occur. When development towards the caudal side becomes disrupted, spina biffida occurs.
Match the following terms to the correct association with tthe developmental divisions of forebrain, midbrain, or hindbrain.
Myelencephalon, Prosencephalon, Tegmentum, Telecephalon, Metencephalon, Tectum, Mesencephalon, Diencephalon, Rhombencephalon
Myelencephalon - Hindbrain
Prosencephalon - Forebrain
Tegmentum - Midbrain
Telencephalon - Forebrain
Metencephalon - Hindbrain
Tectum - Midbrain
Mesencephalon - Midbrain
Diencephalon - Forebrain
Rhombencephalon - Hindbrain
Match the components of the hindbrain with their functions.
Medulla oblongata, Pons, Cerebellum
[Contains white matter tracts to and from nearby regions; houses some cranial nerves; role in respiration/ Plays a role in balance, motor control and coordination; autonomic functions; evaluates movement and behavioral success/ Autonomic functions; some cranial nerves]
Medulla oblongata - Autonomic functions; some cranial nerves
Pons - Contains white matter tracts to/from nearby regions; houses some cranial nerves; role in respiration
Cerebellum - Plays a role in balance, motor control/coordination; autonomic functions; evaluates movement/behavioral success
Match the functions with the associated midbrain subdivisions.
Auditory processing, contains motor pathways;role in pain perception, visual processing, subdivisions have color names
[Inferior colliculus of the tectum, Superior colliculus of the tectum, Tegmentum]
Auditory processing - Inferior colliculus of the tectum
Contains motor pathways; role in pain perception - Tegmentum
Visual processing - Superior colliculus of the tectum
Subdivisions have color names. - Tegmentum
Match the functions with the associated subdivision of the diencephalon (part of the forebrain)
Relay station for sensory input heading to cortex, Produces releasing hormones that regulate metabolism & parts of autonomic nervous system, Role in sleep & consciousness, Organizaed into multiple cell groups (nuclei) by sensory type, Controls the activity of most other hormone-secreting glands, Produces melatonin, which modulates sleep
[Pituitary gland, Thalamus, Hypothalamus, Pineal gland]
Relay station for sensory input heading to cortex - Thalamus
Produces releasing hormones that regulate regulate metabolism & parts of autonomic nervous system - Hypothalamus
Role in sleep & consciousness - Thalamus
Organized into multiple cell groups (nuclei) by sensory type - Thalamus
Controls the activity of most other hormone-secreting glands - Pituitary gland
Produces melatonin, which modulates sleep - Pineal gland
Match the components of the telencephalon of the forebrain with their functions
Cerebral cortex, Limbic System, Basal ganglia [Roles in emotion, memory, smell, controls most of cognition, role in motor control especially initiation and termination of a voluntary movement]
Cerebral cortex - Controls most of cognition
Limbic system - Roles in emotion, memory, smell
Basal ganglia - Role in motor control, especially initiation/termination of a voluntary movement
What are radial glia? How do they play a role in neural migration?
Radial glia are specialized cells in the developing nervous system of all vertebrates, and are characterized by long radial processes. These processes facilitate the best known function of radial glia: guiding the radial migration of newborn neurons from the ventricular zone (inner regions along ventricles) to the mantle regions (outer regions along surface of the brain).
List and describe each of the four stages of neural development prior to birth that we discussed.
Proliferation, migration, determination & differentiation, and synaptogenesis.
Proliferation is the process of the stem cells dividing into two daughter cells, then later reproducing itself with either a neural cell or glial cell.
Neuronal migration refers to the remarkable series of events where neurons move from their sites to their locations in the CNS.
Differentiation and determination: When the neural stem cell either becomes a neruon or a glial cell.
Synaptogenesis: The formation of synapses among brain cells, as well as the process of competition and apoptosis.
What are neurotrophins
Neurotrophins are a family of proteins that induce the survival, development, and function of neurons. They belong to a class of growth factors, secreted proteins that can signal particular cells to survive, differentiate, or grow.
Cells that secrete neurotrophins are called ______.
Guidepost cells
What is apoptosis?
Apoptosis is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes (morphology) and death.
Briefly describe how neural competition and apoptosis combine to develop neural circuits like those that make up a topographical map.
Neural competition is the competition between neurons to bind to their necessary counterparts to build up those circuits. When the neuron fails to find a counterpart, it dies off.
Match the correct descriptions with each developmental brain disorder.
Abnormally small brain size, abnormally smooth brain, caused by a problem with neural cell proliferation, one hemisphere of the brain is abnormally larger than the other, caused by defective neuronal migration, caused by disruption of apoptosis
[Microcephaly, Lissencephaly, Hemimegalecephaly]
Abnormally small brain size - Microcephaly
Abnormally smooth brain - Lissencephaly
Caused by a problem with neural cell proliferation - Microcephaly
One hemisphere of the brain is abnormally larger than the other - Hemimegalencephaly
Caused by defective neuronal migration - Lissencephaly
Caused by disruption of apoptosis - hemimegalencephaly
Down’s syndrome (Trisomy 21) is associated with decreased brain volume, as the chromosomal abnormality leads to problems with which of the following developmental stages of neural development?
Synaptogenesis
Most “brain growth” after birth arises from dendritization (the development of dendrites) rather than new cells.
Why is synaptic pruning important over our lifetime?
Synaptic pruning is a natural process that occurs in the brain between early childhood and adulthood. During synaptic pruning, the brain eliminates extra synapses. Synaptic pruning is thought to be the brain’s way of removing connections in the brain that are no longer needed.
In developmental psychology/biology, what does the critical period refer to
The critical period is a maturational stage in the lifespan of an organism during which the nervous system is especially sensitive to certain environmental stimuli
Germ layers
the three primary cell layers that formed in the earliest stages of
embryonic development, consisting of the endoderm (inner layer), the ectoderm
(outer layer), and the mesoderm (middle layer)
Neural proliferation
a two-phase process in which precursor cells turn into
neurons (phase 1) and glial cells (phase 2). Aspects of proliferation include
symmetrical division (stem cell divides into two identical daughter cells) and
asymmetrical division (stem cell divides into 1 stem cell and 1 neuron/glia cell
(depending on the phase).
Neuronal migration
the remarkable series of events whereby millions of
neurons move from their sites of origin in the ventricular and subventricular zones
to the locations within the central nervous system (CNS), where they will reside
for life
Determination & differentiation
Once in migration is complete, the young
neurons become the precursors that will eventually give rise to various types of
neurons and glial cells. Through differentiation, a given population of neurons gives
rise to subpopulations that are specific to the various parts of the nervous system
