Evolution
What is homology and homoplasy?
Homology- features based on common ancestry
Homoplasy- similar features that evolved separetely
What is synaptogenesis?
the formation of synaptic connections between neurons during brain development!
What is somatosensation?
Sense of touch!
Explain what a rod and cone is
Cones(light)- mostly in fovea, each receptor attaches to a single bipolar cell and a single ganglion cell, direct line to the brain which allows the registering of the exact location of input, 25 million cones
Rods(dark)- periphery of the retina, greater number of receptors converging onto ganglion cells, lacks detail but allows for greater perception of much fainter light involving peripheral, 100 million rods
What are the three types of muscles
1. Smooth muscles- control the digestive system and other organs
2. Skeletal/striated muscles- control movement of the body in relation to the environment
3. Cardiac muscles- are heart muscles that have properties of skeletal and smooth muscles
What is taxonomy and phylogeny?
Taxonomy- classification system of organisms
Phylogeny- evolutionary history of species
through what process does cell death (during development) occur?
how do you define that process?
cell death occurs via apoptosis!
Apoptosis: "programmed" mechanism (gene expression-dependent) for implementing cell death
What are the three tiny bones call in the ear (ossicles)
Malleus, incus, and stapes
What are the two major theories for how we view color
Trichromatic theory- perception occurs through the relative rates of response by three kinds of cones- short, medium, and long-wavelength
Opponent-process theory- we perceive color in terms of paired opposites (blue v yellow and green v red)
What are the two types of skeletal muscle fibers?
1. Extrafusal muscle fibers- do all the work of the muscle (receive input from alpha motor neurons)
2. Intrafusal muscle fibers- contained within muscle spindles (receive input from gamma motor neurons)
What are Darwin's 4 observations?
1. Reproduction increases population size unless factors limit it
2. Individuals in a species are not identical
3. Some variation among individuals is due to inheritance
4. Not all offspring survive to reproduce
what is cell differentiation? and what happens during it (hint: what happens to axons?)
Differentiation: process of cells adopting their phenotype appropriate for the particular brain region
During neuronal differentiation, axons GROW first either during migration OR once it has reached its target and is followed by the development of dendrites
What are the parts of the outer ear, middle ear, and inner ear?
Outer- pinna
Middle- tympanic membrane and ossicles
Inner- cochlea
What are the two types of cells in the visual cortex?
Simple cells- respond to bars or edges with a particular width, location, and orientation
Complex cells- elongated receptive fields, not tied to a location
What are the functions of the basal ganglia?
Initiating movement that is not guided by a stimulus
Critical for learning motor skills
Automatic and habitual behaviors
Big Brain Time!
Explain either the social brain hypothesis or the sexual selection hypothesis
Social brain hypothesis- larger cortex is favored for handling the cognitively complex task of maintaining social relationships
Sexual selection hypothesis- proposes a natural selection for abilities to attract attention, stimulate, and surprise a potential mate; provides an evolutionary basis for understanding human traits
what are the 6 stages in neural development?
1. neurogenesis
2. cell migration
3. differentiation
4. synaptogenesis
5. neuronal cell death
6. synaptic rearrangement
What are the five cell types in the retina?
Rods/cones, horizontal cells, bipolar cells, amacrine cells, ganglion cells
What is the part of the thalamus specialized for visual perception
Lateral geniculate nucleus (LGN)
Most ganglion cell axons project to LGN
What are the 2 major pathways for how the brain controls motor output?
(Bonus points if you know the three tracts associated with one)
1. Pyramidal
2. Extrapyramidal (reticulospinal, rubrospinal, vestibulospinal tract)
What are the 6 basic similarities in nervous systems across all vertebrates?
Development from a hollow dorsal neural tube
Bilateral symmetry
Segmentation
Hierarchical control
Separate systems
Localization of functions
1. What is epigenetics? Define and/or explain the process!
2. When can it occur?
3. What are some examples of what epigenetics account for?
4. What are 2 ways experience affects gene expression? (do not need to define unless you want to)
1. the study of heritable changes in the individual caused by modifications in gene expression (rather than alterations in the DNA itself)
2. during early-life development (pre/postnatally)
3. Drug addiction, various mental illnesses, how early life stress/exposure to trauma increases chance for MDD later in life, metabolic changes, behavioral changes
4. DNA methylation and histone modification
What are the two main streams of auditory processing and where do they project to?
Dorsal path- projects to parietal cortex
Ventral path- projects to temporal cortex
What are the 4 separate representations in the V1 cortex?
1. Location in visual field
2. Ocular dominance- some neurons fire more strongly to one eye vs the other
3. Orientation- lines, edges, objects
4. Color
What are the two major kinds of proprioceptive receptors that convey the state of the muscles and joints to the brain?
Muscle spindle- important for sensing muscle stretch
Golgi Tendon Organ- monitors muscle tension