experiments Flashcards

Question

Disruptive Selection in Spadefoot Toad Tadpoles

Answer 1

Detritivores: consume detritus and small invertebrates Carnivores: consume invertebrates intermediates: are rarer but generalists Observed growth of different morphs when given detritus as food source Result ---- Detritovores did better than intermediates which did better than carnivores Observed ability to catch shrimp Result ---- Carnivores did better than intermediates which did better than detritovores Did a mark and recapture study Results: intermediate morphs survived less well (10%) and they were also much smaller Conclusion: Individuals with specialized traits on either end of the spectrum have higher fitness than individuals with intermediate traits

Answer 2

use 2 strategies to obtain burrows 1- "diggers" dig their own burrows 2 - "borowers" use abandoned burrows Which strategy a wasp uses is genetic --> diggers always dig and borrowers always borrow

Answer 3

males are red, females are greyish brown -- coloration of male ranges from red - orange - yellowish (mostly due to diet) TESTABLE PREDICTION: if females perfer to mate with red males, than red males should get mates more easily EXP 1 followed females behavior w 4 males -- most peferred reddst male (no diff between middle male) EXP2 male feathers were dyed more or less red Result -- females perferred reddest male Conclusion -- red plumage is a sexually selected trait in house finches

Answer 4

- spotted diving off cliffs into water when food is scarce - idea is that they can sacrifice themselves for the greater good Since Natural Selection works in individual genes, group selection can only work if the sacrifice increases the level of sacrifice gene in the remaining population Difficulties with group selection - Cheaters would win - suicidal genes would be lost ACTUALITY - when population numbers are high, lemmings disperse to reduce intraspecific competition

Answer 5

Can study effect of environment on genetically influenced behavior y raising some strain in DIFFERENT ENVIRONMENTS - environments difference in the amount of novelty the animals experienced while growing up (how enriched their environment was) offspring of dull or bright RESULTS: Restricted: Dull and Bright made around the same amount of errors Normal: Dull made almost the same amount as restricted, bright made about half Enriched: Both dull and bright made a lot less errors, bight made slightly less

Answer 6

Exp 1: Identified hives that bred true -- crossed hygienic with unhygienic Result -- all offspring unhygienic Conclusion -- unhygienic behavior dominant AND hygienic hive must be homozygous recessive and the unhygienic hive is homozygous dominant as well Exp 2: Backcross the heterozygous unhygienic offspring with hygienic homozygous recessive parents Result: 4 different types of behavior seen Ultimately -Behavior was split into 2 diff behaviors: uncapping and removal - some bees did both - some did neither - some only uncapped - others removed (if someone else already uncapped) Cannot explain with only 1 gene U - no uncapping u - uncapping R - no removal r - removal

Answer 7

- obtained 10 sets of 4 sibling larval salamanders - raised each larva along on an aquarium with a hiding place so that they did not interact with others put salamander in tank with regular water (low predation) pumping in , then with water from a tank with predatory fish (high predation risk) - measured how much time spend in the refuge - "low risk" larvae spent less time in refuge than the "high-risk" larvae linear correlation between time spent out of refuge 'safe' and when it was 'risky' bold when safe still bold when risky Implies that the phenotypic expression can be due to genetics Siblings were similar to each other - implying that the phenotype of being bold or shy has an underlying genetic basis (they didn't interact with each other – suggest

Answer 8

EXP 1: makeing knock-out mice that lacked NMDA gene - then tested for ability to remember spacial arrangement of a swimming chamber (hidden platform test) Result --- knock-out mice were slower than normal than the controls for learning position of platform EXP 2: over-expressed NMDA - "knock-in" mice Result --- learned more quickly than normal controls CONCLUSION --- NMDA is involved in learning and memory -- not expressed all the time bc it can be associated with increased pain perception and neurodegenerative problems

Answer 9

when bees leave to go find food, only 25% act as food scout to find NEW food sources -- rest are followwers Q -- what makes a scout be a scout Liang et. al 2012 - put a series of diff. feeders in a huge flight cage, those that found multiple sources were called scouts --- then conducted a whole-genome RNA analysis on scouts and non-scouts RESULTS 16% of mRNA transcrips exhibited signifiant diff between scouts and nonscouts -- many of genes related to neurotransmitters associated with novelty-seeking behavior in vertebraes POINT -- behavior is likely influence by which genes are active

Answer 10

in the picture of all the ants -- all could be genetically identical - difff shapes and sizes reflect gene expression triggered by chemicals i the foods that worker ands feed to the larvae

Answer 11

1.) object contact triggers Ca 2+ channels to open 2.) Ca2+ enters cell and triggers biochemical event leading to reversal of cilila 3.) rxn follows lenth of cell, all cillia are reersed 4.) after tiem Ca2+ channels close

Answer 12

Locusts have 2 sets of wings arising from the thoraz -- flight is powered by "indirect" flight muscles what to know how NS is organized -- ex: command center or response to sensory feedback or central pattern generator CONTROL --> put locust on a stick and test for flight control using a rigid tether 1: test command center by removing brain -- 2--- test requirement for sensory feedback by removing sensory structures in wings --- 3--- only nervous structures in thoracic ganglia -- which must somehow turn the system on and keep it going -->>> definition if central pattern generator

Answer 13

recordings from neurons that are active when Tritonia swims: the DFN are the dorsal flexion neurons and the VFN are the ventral flexion neurons ^^ MOTORNEURONS that cause muscles of the body wall to contract (alternating firing) Central pattern generator kes the DFN and VFN fired alternately 2 sets of 3 DSI 2 sets of 1 C2 2 sets of 1 VSI sensory info comes into the DRI (processes all the info )

Answer 14

toads have a stimulus filter that allows them to detect worms in an environment full of other things hunting in toads 1 - wait until prey moves close 2 - turn to face the prey 3- zap with their long sticky tongues - measured the rate of turning toward an image as image was moved --- all had to be moving mostly eat long horizontal inhibitory photoreceptor and excitatory photorecptor send signal to ganglion cell (filters/balances amount) -- sends info to optic tectum of toad brain (more visual processing) outer photoreceptors -- tend to inhibit ganglion cell and the inner ones excite it

Answer 15

Why sometimes the moth dives and other times it simply gets out of the way noctuid moth eats have 2 nerve cells in the ear, and the thin tympanum vibrates in response to a sound (when a sound is near) 2 paths the info can follow 1.) reflex path goes from the ear to the flight muscles, bypassing the brain 2.) a path to the brain via interneurons in the thoracic ganglia along the nerve cord A1 and A2 cells respond to same sounds differently low intensity: A1 has a gradient respnse, A2 doesnt really respsons Moderate intensity: A1 inc action potential, A2 still doesn;t really respond High intensity: Both give a strong response ^^ A2 is not gradient Habituation in the A1 cells allows stilulus filtering of background sound --- if sound stays the same (tune out) --- of sound is pulsed -- BAT --- doesn't ignore HOW THEY RESPOND -- if sound is really loud -- A2 cell responds (loud means close by) == PANIC -- reflex to close wing -- A1 can only tell if sound is from above

Answer 16

A1 cells responded when bat was 2 ft away and A2 cells responded when bat was there

Answer 17

1.) action potential arrives at the axon terminal and Na+ enters area -- area becomes positive 2.) causes Ca2+ channels to open, Ca2+ rushes in 3.) causes synaptic vesivles containing neuotransmitters to fuse with cell membrane - dump neurotransmitter into synaptic cleft 4.) neurotransmitter binds to receptors on surface of post-synaptic cell and causes ion channels to open

Answer 18

- no neurotransmitter release - no signal recieved by motorneuron - no signal sent to muscles so no gill withdrawl

Answer 19

ADDING substance of interest - bathe hungry and satiated leeches in serotonin - analyze behavior and physiological responses RESULT: satiated leeches acted hungry - stimulate the serotonergic neuron in the leech brain -- natural source of serotonin - analyze behavior and physiological responses RESULT: satiated leeches acted hungry REMOVING substrate of interest - block action of seretoniin with 5,7 - DHT - analyze RESULT: hungry leeches acted satiated interaction of feeding behavior and brain -- matched leeches in paires according to size and allowed on of each pair to feed till satiated - measured amount of serotonin in brains of hungry vs. satiated leeches RESULT -- satiated leeches had less serotonin

Answer 20

- reptile where gonads shrink outside of breeding season - testes regrow in response to warm temperatures in the spring - growth of testes casues increase of testosterone

Answer 21

- reptile in which testes shrink at end of breeding season and grow back after hibernation - hibernation needed because this subspecies found in cold areas of upper midwest, US, central canada - when male emerges from hibernation, it carries out courtship and mating even though testes have not grown back yet and testosterone is at zero EXPERIMENT: captured animals at end of summer when T levels still high THEN - half were left intact as controls - half were castrated so that there was no source of T - followed for 4 years RESULTS (during next 3 years) - %. of intact males who courted femals stayed high - % of castrated males who courted decreased each year CONCLUSION: in years 2 and 3, intact males had testosterone in the previous summer while castrated ones did not -- it looks like testosterone affects behavior months later Added testosterone to the castrated males and courtship retuened

Answer 22

Massaro, Seitawan, and Davis 2007) An increase in prolactin is associated with egg incubation behavior in female penguins wanted to know if prolactin levels were affected by 1.) the sight of an egg (visual stimulus) OR 2.) the feel of an egg (tactile stimulus) 2 kinds of stimules - provided visual stimulus -- fake egg near nest - provided tactile (and visual) stimulus in nest RESULTS Birds than could only see eggs did NOT have elevated levels of prolactin (prior and visual were not sig diff) Birds that had eggs added to nest DID have higher prolactin levels than controls CONCLUSION presence of an egg in nest results in increased prolactin production in these birds -- hormones are altered by experience

Answer 23

male behavior = mounting female behavior = lordosis - testosterone during days 1-5 has an ORGANIZATIIONAL effect - days 1-5 represent a CRITICAL PERIOD for that organizational effect given that castration has no effect during days 6-10 - Testosterone has an ACTIVATIONAL affect in adulthood males that were castrated and not given testosteron during the critical period showed signs of lordosis Female brain does not respond to testosterone in adulthood - so there is no activational effect

Answer 24

Polygynous males mate with a female and then move on to seek another female, while the female builds a den and raises her pups alone. Prairie voles are typically monogamous. Male and female mate, form a social bond, and build a den together. The male helps care for the pups, often ‘huddling’ with them to keep them warm while the female seeks food. Medow voles: polygynous Prarie voles: monagamous Cross-Fostering Experiment: - Baby meadow voles put into a nest of praire voles - prairie vole adults accepted them as onw CONTROL - baby meadow put into best of other meadow vole RESULTS - cross-fosterd female meadow voles spent more time than controls cuddling and nursing young 4 of 8 cross-fosterd MALE nested with their mates and were monogamous CONCLUSION parental behavior is highly influenced by environemt BUT 4 of 8 cross-fostered males were still poly -- GENES still can play a role HORMONE: vasopressin -- released in males when having sex w same female (feelings and pleasure center) avpr1a

Answer 25

Made 3 hypo praire lines 1.) avpr1a-VP: had an extra copy of avpr1a expressed in the ventral pallidum (reward center) 2.) Avpr1a-CP: an extra copy was expressed in a different brain area, caudate putamen (not related to reward center) 3.) lacZ-VP/CP: bacterial lacZgene was expressed in VP and CP as control RESULTS - males that had extra vasopressin receptors in the ventral pallidium spent mpre time with female Meadow voles do not usually have receptors in the ventral pallidium -- dont feel reward

Answer 26

- anaimals don't stat life with all possible behaviors - some are acquired - packing pollen and really foraging ae acquired Correlation of (for) gene expression with nurse/forager transition in brains of nurses and foragers in three honey bee colonies

Answer 27

correlation: JH is low in nurse bees, but higher in foragers Add JH - become precocious foragers Remove JH - transition to forager delated when Jh added back after removed - normal behavior

Answer 28

added bees at an age that should normally be nurse bees to bees that were already foragers - if you added more young bees - resident young bees switched to being foragers when older bee provides food to younger bees, transfers a compound called ethyl oleate -- slows down forager transition (acts as pheromone)

Answer 29

birder were either fed 1.) whole sunflower seeds (could be stored for later) or 2.) powdered sunflower seeds (which had to be consumed at the feeder) - birds recieving whole seeds and storing them had a larger hippocampus - learns location (NS actially changing structure in response to environment)

Answer 30

had to learn and be able to map out 25,000 locations in London - hippocampys was diferent: larger in posterior and smaller in anterior did a study --> trainees who passed the test had substantial growth of the hippocampus compared to those who did not

Answer 31

genetics of being male leads to estrogen production in male brains during emryogenesis estrogen masculinizes the brain by triggering growth of the song areas brains start out the same but diverge over time

Answer 32

- add estrogen pellets of nestling female zebra finch -- show same growth in song areas as males do - 15/18 treated females produced male-like songs

Answer 33

- young male needs to hear his song during listening phase in order to preproduce it later on CRITICAL PERIOD 10-50 days after hatchign FoxP2 gene is expressed in Area X during "listening phase" resarchers used knockdown technique to reduce expression of FoxP2 ----- didn't sing as well --- FoxP2 is required for normal developent

Answer 34

- listening to itself experiment: deaf son --> can't match father's tone

Answer 35

own species biase ---- played WCS and Song Sparrow recording -- bird learned its own species song but play WCS recording and house the bird w a living song sparrow male -- will use live bird as a tutor

Answer 36

brood parasite -- lay egg in other nest - no listening phase - born knowing full song male cowbirds learn place - they do not learn their own song (inate) but they can learn to modify song to produce a particular dialect born knowing notes of borth versions - alter depending on audience

Answer 37

Konrad Lorenz - critical period - triggerd by spcific stimuli - is more or less permanent role of sound and movement

experiments Flashcards

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