Unit 11: Evolution Flashcards
evidence of evolution?
earth is old
- valcano, layering of rock, uplifting of mountain etc
what are hard fossils?
bones or shells
what are soft fossils?
frozen animal in glacier or insect inside amber
how old is a fossil with 25% C14 (radioisotope dating)?
100 /2 = 50
50/2 = 25
2 half lives
1 half 5700 year, 5700 x 2 = 11400 years
what is homologous structure? examples? also known as?
SAME STRUCTURE (ANCESTOR), DIFFERENT FUNCTION
always go with DIVERGENT EVOLUTION
ex: Pentadactly limbs, comparison of embryos, adaptive radiation
- homologous structure + divergent = adaptive radiation
sWhy are homologous structures evidence of evolution?
show how organisms share a common ancestor but through divergent now have different functions
what are Analogous structures? ex?
DIFFERENT STRUCTURE (ANCESTOR), SAME FUNCTION
analagous = covergent evolution
ex: butterfly & birds
why are analogous structures evidence of evolution?
show how different groups under the same selective preassures evolved to have same function
what are vestigal structures? ex (2)?
vestigal = 廢掉
structures in the body that has no importance (no function anymore)
ex: coccyx (human tail bone), pelvis in whales
what is artificial breeding?
selective breeding/animal husbandry (choosing desirable traits to inherit)
how does artificial selection show evolution?
shows that organisms are mutable even though humans caused the change, not nature
cons of selective breeding?
ex:
- selective breed apple bigger, but heavier and will easily break + damage tree
- breeded dogs have health problems
what is evolution?
the process which populations change over time in response to their environment
how does evolution happen?
natural selection (nature choosing features that give organism better fitness), selective preassure -> variation (from crossing over, independent assortment, mutations)!
what does better fitness mean?
features beneficial for survial + reproductive success
how do mutations happen?
randomly and common due to DNA replication mistakes
what are effects of mutations?
harmful, neutral, or beneficial
how can mutations be harmful?
mutation: humans creating less vitamin C
before: lots of vitamin c by nature so no need for more vitamin c
after: moved to other parts of the world, less vitamin C produced by humans cause mutation, so harmful cause not enough vitamin c now
what is adaptation? cost ex?
features that enable better fitness
HERITABLE + KEEP FOR A LONG TIME
ex: human brain bigger, but takes a lot of energy (ATP) to grow
what is acclimation?
temporary inheritable
plant acclimation of leaf stomata lab?
calculated density of somata (pore under the leaf where CO2 enter and oxygen+water vapor leave) in sun + shade
sun: more stomata! more acclimated more cause more sun = more photosynthesis
shade: less stomata! less acclimated cause less sun = less photosynthesis
sexual selection ex?
female choice: 女peackocks choose 男peackock
sometimes bad cause female choice = reproductive success but somestime cost of survivorship (peacock tail too long)
what is antibiotic resistance? ex (3)?
bacteria getting more resistant to antibiotics
- antibiotics fed to all animals whether they’re sick or not, creates stronger bacteria and end up on other foods
- sometimes doctors prescribe antibiotics to those who don’t need them
- when a patient doesn’t complete their antibiotics (antibiotics haven’t fully killed bacteria yet, remain bacteria more resistant against antibiotics and divide rapidly while passing favorable genes (those resistant against antibiotics)
what happened to peppered moth and industrial melanism?
- moths ariginally white and can hide in white lichen on tree
- industrial revolution = pollution caused lichen to be darker, white moth can’t blend in anymore
- by natural selection, there become more black moths then white
