Exam 2 Flashcards
A husky having more coats than a lab would be an example of
Variation- INDIVIDUALS WITHIN A SPECIES differ in terms of anatomical physiological and behavioral traits, certain traits are more preferable in certain environments
How do the finches help Darwin’s argument of natural selection
competition for food causes variation in beak size between ground finches (seeds) and tree finches (fruit and insects). those that can’t eat enough don’t survive and don’t pass down disadvantageous traits
How did peacocks hurt the argument of natural selection? What addition to the argument did they make way for?
feathers are in no way advantageous for survival. detrimental most likely- bulky and attention drawing. Made way to argue that the likelihood of passing genes on also depends on traits that make you a more desirable mate- Sexual selection
list of taxonomic (phylogeny) classifications
Kingdom, Phylum, Class, Order, Family, Genus, Species
Kingdom
All living beings divided into five kingdoms (e.g. animalia, plantae, etc.)
Phylum
main subdivision of a kingdom, e.g. vertebrates, invertebrates etc.
Class
subdivision after phyla- Mammals, birds, reptiles
Order
subdivision after class- carnivore, primates
Family
felines, canines, etc
Genus
Dogs, wolves, coyotes, etc
Species
domestic dogs
Homology
Similarities in features due to common evolutionary heritage- same structure may have different function
Are brains typically homologous?
Yes
All vertebrate brains share what basic features?
Develop from dorsal neural tube Bilateral symmetry Segmentation (Hind-mid-forebrain) Hierarchical control (fore>mid>hind) Localization of function (area based functions) Separate PNS and CNS
Why are invertebrates good for studying
less complicated systems. nematodes are translucent
independent evolution of functionally similar characteristics (convergent evolution) bats and butterflies have wings but not same bone structure
analogy
The use or disuse of some structure or behavior causes an increase or decrease in that behavior T or F and name of this theory
Lamarckian evolution. False. this sort of leads to epigenesis
evolution research is restricted to the study of natural history. cannot be studied using contemporary experimental methods T or F
False. William Dallinger and the temperature change experiment proved otherwise
evolution of a mutation can occur without the mutation having an adaptive value t or f
T
Change in the frequency of a trait in a population due to random sampling
Genetic drift
Founder effect
change in the frequency of a gene variant in a population due to random sampling
Vestigiality- giraffe nerve example from class was not an intelligent design but once served a purpose
traits that were adaptive to an ancestral organism which no longer serve any function (ostrich wings) “non adaptive traits” People having blind spots is not adaptive, octopus has no blind spot
do reptiles have an optic tectum? location of optic tectum?
no- superior colliculus in midbrain
maladaptive traits
do not work in favor of a species survival, but were selected for typically for reproductive success (big ass elk antlers) or by chance. pigeons peck at shit they associate with food. not just food
there is now huge variation in humans due to modern medicine, why?
people that normally wouldn’t survive or reproduce in nature have easier lives. this allows them comfort and longevity, more chances to reproduce
difference between human and chimpanzee brain?
chimpanzee brainstem exits toward the back instead of down. chimps do everything humans do, just a little bit worse
thought to be a major contributor to increased cerebral volume throughout evolution (seen in humans and apes)
bipedalism. having more access to hands rather than standing on all fours means increased time to use the hands and learn things with the hands
another physiological component to increased brain size in humans (mutation)
mutation caused overall weaker musculature. weaker jaw muscles means less space and architecture required for mandible, giving brain room to expand
ecological niche
brain develops to efficiently aid organism in survival in its natural habitat. more brain space is dedicated to anatomy/physiology that plays big roles in survival. brains evolve for efficiency, not power. thats why manatees don’t have smart ass fuckin brains- dont need them.
do socialization and mean clique size correlate with an increase or decrease in the evolution of brain size?
increase
food storage is related to what brain structure? why?
birds that store their food have a bigger hippocampus than non-food-storers. the hippocampus forms mental maps and allows animals to keep track of areas where they have hidden food
bigger brains always means better chance of survival true or false
false. brain needs to be efficient. too big of a brain that isn’t necessary may cause unneeded intercranial pressure and kill the organism
encephalization
brain size relative to body size is most important. Brain weight/body weight^.69
second largest encephalization factor in primates? example?
capuchin monkeys exhibit social learning and culture through tool use. Banging rocks on nuts is a learned skill. the monkey will not do it if it is raised in captivity
what has the largest encephalization factor of any invertibrate?
octopus
what factor besides encephalization is important? what separates the reletively equal encephalization factors of the capuchin monkey and the capybara?
neuron count. monkeys have way more
the ratio of what area of the brain compared to other areas is also a predictor of intelligence?
cortical areas
how can intelligence be maladaptive?
more oxygen required for brain- uses 15-20% of O2, glucose, etc.
long gestational and postnatal developmental periods
more genes needed for brain construction, increasing chances of mutations leading to cognitive and behavioral disorders
weapons of mass destruction
Morphology
Physical shape of things, development of different structures
What influences what? (Behavior, Physiology, Morphology)
Behavior is influenced by morphology and physiology, and can also influence both in return
SIX STAGES OF NEURONAL DEVELOPMENT
Neurogenesis, cell migration, cell differentiation, synaptogenesis, cell death (major part of brain development), synapse rearrangement
Much of neuroplasticity in adults is due to what?
synapse rearrangement
How do neural stem cells migrate
traveling up radial glia
Growth cones and their function
Synaptogenesis. extend from axons and dendrites, attracted to target cells via chemical signals called chemoattractants- can be repelled from other cell groups or locations by other signals called chemorepellents
T or F there is a code within every neuron that determines its future function
False. It is shaped by cells/chemicals around it
Important factor in synaptic connectivity (think behavior)
the human experience! different experiences and uses of neurons increase or inhibit their function and others like them
What prenatal structure is the basis of all brain development?
Neural tube
The ventricular system arises from what structure?
central canal of the neural tube
when does the neural tube present itself?
3 weeks
what part of the neural tube grows way more than every other part?
forebrain
Where is the optic tectum located?
midbrain
T or F- ALL vertebrates have optic tectum
T
control embryonic development of structures like limbs and eyes. regulate expression of networks of other genes by switching them on or off in various parts of the body. its target genes promote cell division, differentiation, cell migration, etc
hox genes
when ultrabithorax gene mutated, what happens?
growth of a second thorax/wings
When antennapedia gene (control of network of genes leading to development of legs) is switched on in the head segment, what happens?
fly grows legs where antenna should be
Olfactory pathway DRAW
Air-{(OLFACTORY EPITHELIUM) olfactory cilia-olfactory receptors-olfactory bulb}-Amygdala, hypothalamus,and prepyriform cortex (primary olfactory cortex)-amygdala and prepyriform cortex also communicate with hypothalamus, and the medial dorsal thalamus-orbital frontal cortices
Olfactory transduction, what system? process?
Secondary messenger. odorant binding to receptor activates g protein with GTP which activates adenyl cyclase releasing cAMP to open ion channes for depolarization
how many functional receptor TYPES do people have? how many receptors altogether? dogs and mice? what causes this difference
350 compared to +1000, 6 million compared to 220 million in dogs. people are less reliant on the sense of smell for survival and communication. DOLPHINS HAVE 0
T or F olfactory neurons cannot regenerate
F. new set every few weeks
Vomeronasal Organ
Animals detect pheromones that cause different behavior through accessory olfactory bulb in cortex. VNO is located superior to hard palate
T or F the Vomeronasal organ connects directly to the thalamus
F. no thalamic connection
Gustatory pathway
Taste buds on papillae-cranial nerves VII, IX, X-Solitary tract in brainstem-thalamus-gustatory cortex
T or F different papillae have specific taste buds according to their location
F. each papilla has buds for each taste, but have diversity of number of buds
Receptors for umami (two identified) respond to what?
MSG- monosodium glutamate. meaning glutamate is probably sufficient
What group is more sensitive to taste and smell, men or women?
women. more taste buds means more taste
when sweet taste receptor hT1R2-hT1R3 is altered to be responsive to acidic pH, what occurs?
The individual can perceive sour tastes as sweet. sour tasting things are acidic
What would happen if you had an nonfunctional T1R2 mutation?
cannot taste sweet things
What taste can whales (cetaceans) experience
salt
function of taste receptors outside of mouth?
signals for toxins that induce sneezing, coughing, vomiting, diarrhea, etc
Fourier analysis
summation of a bunch of general functions to analyze a complicated one
Auditory pathway
tympanic membrane-ossicles-cochlea (basilar membrane)-cochlear nucleus-superior olivary nucleus in brainstem (info from right ear crosses to left side, vice versa)-inferior colliculus-medial geniculate nucleus-auditory cortex