EVOLUTION Flashcards
1
Q
cells
A
basic/smallest unit of life that come from a pre existing cell
2
Q
DNA na proteins
A
- both depend on eachother
- DNA is capable of storing information
- cells rely on proteins to grow, replicate and survive, but they are unable to store information
- DNA needs proteins to function, and proteins need DNA to exist
3
Q
RNA world hypothesis
A
- self replicating RNA emmerged, multiplied and evolved
- through survival of the fittest they evolved into strong and stable proteins
- RNA mutated into double helix DNA that became a storage for successful RNA and proteins molecules
- life got more complex, until RNA has adapted to become an essential part in cells
4
Q
Miller and Uray experiment
A
- aimed to simulate the conditions thought to exist on early earth, and investigate the origin of life
- created a laboratory set up that simulated the atmosphere of early earth, and they subjected the atmosphere to a continuous cycle of electric sparks, representing lightning to simulate the energy input
5
Q
life on earth
A
- dated back to 3.8bya
- there was a lot of water and CO2 available for photosynthesis
- photosynsthetic organisms preferred to use the more stable isotope of C13 therefore there was a higher ratio of C13:C17
- this ratio was found in rocks dated back to that amount of time. also lipids on these rocks indicate organic material
6
Q
where life originated
A
- surface tide pool panspermia, or under a thermal vent
- life originated in very harsh environments
- exobiology states that if life can appear in very harsh environments, it can appear anywhere
7
Q
Lamarck
A
- he proposed the first theory of evolution
- built his idea on the fact that individuals change by acquired characteristics
- today we know that acquired characteristics are not inherited so a species cant change because of it
8
Q
Darwin
A
- second theory of evolution
- natural selection states that in populations of organisms, individuals with heritable traits that are better suited for their environment are more likely ro reproduce, passing down those advantageous traits
9
Q
genetic diversity
A
- variety of traits present in a population
- a higher generic diversity provides greater pool of potential traits, increasing the chances of beneficial traits being present when environmental conditions change
10
Q
environmental change
A
- when this happens, certain traits may become more advantageous or disvantageous for survival
- natural selection will act upon existing variation in the population
11
Q
selection
A
- process in which certain traits become more or less common in a population over time
- occurs as a result of differential reproductive success among individuals with different traits
- selective pressures in the environment such as competition or predation determine which traits a re advantageous or disvantageous in the environment
12
Q
adaptation
A
process in which populations come better suited to their environment through natural selection
13
Q
endosymbiosis
A
- proposed by lynn margulis that caused a paradigm shift
- this theory explains how eukarioric cells came to be
- some organelles in eukaryotes looked like those of prokaryotes
- prokaryotic cells engulfed other cells through endocytosis, and instead of digestion it, the host cell made a symbiosis relationship with the new cell, making the first cell appear
14
Q
evidence for endosymbiosis
A
- similarities between organelles and free living bacteria
- mitochondria and chloroplasts having double membrane structure
- mitochondria and DNA haviiing their own DNA separate from the nuclear DNA of an eukaryote
- mitochondria and chloroplast replicating through binary fission
- evidence of other endosymbiosis events in nature
15
Q
homologous and analogous structures
A
- homologous structures are anatomical features found in different species that have a common evolutionary origin
- analogous structures have similar functions but different structures as they evolved differently
- these structures provide evidence for common ancestry and adaptation
