Lecture 1A & 1B Flashcards
(31 cards)
In which stage of neural tube development do most defect occur, and what are the two types of defects which occur?
- Neural Tube
2. Cranial end defects and Caudal end defects
Name the stages of neural tube development:
Neural plate –> Neural fold –> Neural tube
What are the caudal end defects?
- Spina bifida occulta
- Spina bifida cystica
- Meningocele
- Meningomyelocele
- Meyloschisis
Name the cranial end defects:
- Ancephaly
- Arnold-Chiari deformity
- Holoprosencephaly
What day(s) in embryological development do the cranial and caudal ends close?
Day 27 - Cranial
Day 30 - Caudal
The five parts of the pentapartite brain include:
- Telencephalon
- Diencephalon
- Mesencephalon
- Metencephalon
- Myelencephalon
The prosencephalon, mesencephalon, and rhombencephalon make up the ________ brain?
Tripartite Brain
The vital reflex center is located in what part of the brain?
Metencephalon (Medulla)
What are the components which make up the vital reflex center?
- cardiac center
- vasomotor center
- centers related to respiration
The Medulla is made up of the _____ and ______.
pyramids; pons
The sleep center and the respiratory center are located in what part of the brain?
The pons of the medulla
The diencephalon is composed of what three parts?
- Thalamus
- Epithalamus
- Hypothalamus
The cerebral cortex and the olfactory bulbs compose what part of the brain?
telencephalon
The somatosensory axis uses which type of neurons?
Afferent neurons
Afferent neurons are arranged into series of three, what is this series of three and what are their pathways?
- Primary - receptor –> spinal cord/brain stem
- Secondary - spinal cord –> thalamus
- Tertiary - thalamus –> cerebral cortex
Which axis is involved in transmitting a sensory signal from peripheral receptors to higher brian center?
Somatosensory Axis
What does the skeletal motor nerve axis do?
Transmits an AP from the higher brain centers to the skeletal muscles.
Which neurotransmitters are inhibitory?
Norepinephrine (also excitatory)
Dopamine
GABA
Glycine
Which neurotransmitters are excitatory?
Acetylcholine
Norepinephrine (also inhibitory)
Glutamate
Direct spread of electrical current by ion conduction in the fluid of the dendrites but without generation of AP describes what?
Electronic conduction
Describe fatigue of synaptic transmission in dendrites:
There is less firing over time; occurs from over use
What is described by the gradual loss of AP in dendrites?
Decremental conduction (They are long, thin and leaky)
What part of the brain is used as the relay center for the efferent neurons and afferent neurons?
Thalamus (part of the Diencephalon)
What are the factors that determine firing rate of dendrites?
Above threshold = continue to fire; depends on inhibitory signals
