Electron Microscopy Analysis of Interspecific Variation in Mitochondria and Synapses in the Cerebral Cortex Across 18 Mammalian Species

The brain’s cerebral cortex consumes a large proportion of the body’s energy budget due to the metabolic demand of synaptic signaling. Mitochondria are organelles that generate most of the chemical energy used by cells. In this thesis, I undertook a comparative study in 18 mammals to analyze associations amongst densities of mitochondria, synapses, and neurons in an ultrastructural evaluation through the primary visual cortex. The results for neuronal scaling showed a decreasing density as brain size increases, which concurs with published trends. The results for synaptic density demonstrated invariant numbers across the mammalian clade, which also agrees with the published literature. Unique to the current study is the finding that mitochondrial density is also invariant across the mammalian clade, as shown by a broad sample of mammalian species, inclusive of both large and small brain size variants. Additionally, mitochondrial density did not show a relationship with either neuronal density or synapse density. Overall, the findings from this thesis provide insight into the constraints on metabolic dynamics of cortical structure across mammals.

Author

• Karl, Molly Therese

Language

• en

Keyword

• Primary Visual Cortex
• Neuroscience
• Mitochondria
• Synapse
• Variation

Date created

• 2021

Type of Work

• Master's Thesis

License

• All rights reserved

Rights statement

• In Copyright

GW Unit

• Human Paleobiology

Degree

• M.S.

Advisor

• Sherwood, Chet C

Persistent URL

•  https://scholarspace.library.gwu.edu/etd/76537209p