Describing the Brain Flashcards
(102 cards)
What is the process called by which the neural plate folds to form the neural tube?
Neurulation
Name the following parts of the neural plate:
What causes the neural plate to fold to develop the neural tube?
Neuroectoderm receives a signal from the notochord - this causes the cells to thicken and the lateral margins to fold inwards to form a neural tube.
What is primary neurulation?
When the lateral edges of the neural plate fold upwards & inwards, joining and fusing.
What is secondary neurulation?
Neural tube forming with the cavity in the centre
Why does the neural plate become a tube?
Because the cells in the middle increase, the plate becomes thicker and heavier here, causing it to move down whilst the plate margins move upwards.
When does neurulation occur?
In weeks 3-4
What does the neural tube become in the body?
The brain and spinal cord, the meninges and cranial bones.
How common are neural tube defects?
1 in 1000
What is Anencephaly?
Failure of the anterior neuropore to close.
What is spina bifida?
Failure of the posterior neural tube to close (creates open vertebral canal)
What are the two types of spinal bifida and what is the difference between them?
Spina bifida occulta (hidden, vertebral arch defect only)
Spina bifida cystica (meninges project out of the body)
How many primary brain vesicles are there?
3
How many secondary brain vesicles arise from the 3 primary brain vesicles?
5
What are the primary brain vesicles called?
Prosencephalon
Mesencephalon
Rhombencephalon
Which primary brain vesicle becomes the forebrain?
Prosencephalon
Which primary brain vesicle becomes the midbrain?
Mesencephalon
Which primary brain vesicle becomes the hindbrain?
Rhombencephalon
Which secondary brain vesicles arise from the prosencephalon?
Telencephalon
Diencephalon
Which secondary brain vesicles arise from the mesencephalon?
Mesencephalon
Which secondary brain vesicles arise from the rhombencephalon?
Metencephalon
Myelencephalon
What does the telencephalon become?
Cerebral hemispheres
What does the diencephalon become?
Thalamus
What does the mesencephalon become?
Midbrain