Exam 8: Activity-Guided Neural Development

Some motor units are large, with a single motor neuron stimulating thousands of individual muscle fibers; some motor units are small, with a single motor neuron stimulating less than a hundred individual muscle fibers. What is one potential benefit of this variety in motor unit size?

In long-term potentiation, pre-synaptic glutamate release can be increased by

Sympathetic and parasympathetic neurons have different effects on a target organ because they

The number of synapses in the human cortex _______ rapidly from adolescence to adulthood and _______ from adulthood to old age.

Ocular dominance bands appear in layer IV of the visual cortex in mice even before rods and cones in the retina can respond to light, suggesting that _______ required for the segregation of input from the two eyes.

In what way is the organization of the lateral geniculate nucleus and layer IV of the adult primary visual cortex similar?

Apoptosis that occurs in motor neurons during vertebrate development can be postponed by

The elimination of polyneuronal innervation in the neuromuscular junction is mediated by

Refer to the figure. Curare is a toxin that blocks acetylcholine receptors, including those at the neuromuscular junction (NMJ). Based on the experimental data from chick embryos that were treated with curare (red line) and control chick embryos (blue line), what happens to motor neurons when the communication between motor neurons and muscles is silenced? What would you expect to happen when curare is removed? What does this suggest about normal motor system development?

In developing autonomic ganglia,

What type of activity in motor neurons drives the elimination of polyneuronal innervation in the neuromuscular junction?

Refer to the figure. Using the number labels in shown the visual fields of the figure, list which parts of the visual field would be affected by a lesion in right optic tract (marked in red).

In the development of the human cortex, neuronal activity leads to an increase in

What mechanisms allow spontaneous neuronal activity to spread across the developing retina?

Name three classes of ionotropic glutamate receptors. Which one(s) participate in long-term potentiation?

When hippocampal afferents are stimulated at a slow rate,

How do autonomic ganglia in newborn mammals differ from those in adult mammals?

What is long-term potentiation (LTP), and what is one region in the brain where this occurs?

The last region to fully mature in the human brain appears to be the

By which pathway does visual information travel to be interpreted by the vertebrate brain?