Chapter 8

Question 1

The human brain is comprised of ______ neurons and ______ glial cells

Answer 1

• over 80 billion

- at least as many

Question 2

What are the three stages of the organization of human neurodevelopment?

Answer 2

1. Generation of neurons and glial cell types
2. Migration of new cells to their final positions
3. Maturation into fully functioning cells

Question 3

What are the two zones of germinal telencephalon?

Answer 3

the ventricular zone and subventricular zone

Question 4

When does the generation of glial cells peak in humans?

Answer 4

Around birth

Question 5

What is a difference between humans and other animals in the generation of neural cell types, and what role does it play?

Answer 5

• The prolonged period of neuronal and glial production

- regulates brain size and maturation of neural circuits

Question 6

Excitatory neurons in the cerebral cortex utilize which neurotransmitter?

Answer 6

glutamate

Question 7

Inhibitory neurons in the cerebral cortex affect ______ and comprise ______ of all cortical neurons

Answer 7

• GABA

- 15-25%

Question 8

The ventral forebrain is important in generating ______

Answer 8

human cortical interneurons

Question 9

The first generated neurons settle _____, forming the ______

Answer 9

• above the ventricular zone

- early marginal zone (primordial plexiform layer)

Question 10

How do newly formed pyramidal neurons move and in what order?

Answer 10

• either through somal translocation or while attached to radial glial fibres
• inside-first, outside-last order

Question 11

In mammals, what types of spatial information must be imprinted onto neurons of the developing cerebral cortex?

Answer 11

• their position in the radial direction

- their position in the tangential plane

Question 12

What is suggested to be the driver of phenotypic evolution?

Answer 12

the differences in expression of genes

Question 13

What type of gene expression has changed the most in humans compared to other primates?

Answer 13

genes in the brain

Question 14

What are two differences in genes between human brains and other primates’ brains?

Answer 14

In human brains:

• more genes with a delayed expression pattern
• genes involved in synaptogenesis have a prolonged expression pattern

Question 15

Ways to find which species-specific differences are functionally and developmentally meaningful:

Answer 15

• transgenic mice carrying human-specific genetic variations
• in utero electroporation
• human neural progenitors

Question 16

What does the locus coeruleus do?

Answer 16

Integrates information about brain arousal states