CCA Semester 1 Flashcards
Point Mutation (number)
1
Point Mutation (definition)
single gene mutation, possibly resulting in an altered phenotype
Point Mutation (example)
Icefish gained the anti-freeze gene as a result of a gene that over time gained a lot of point mutations until it served an entirely new function
Gene Duplication (number)
2
Gene Duplication (definition)
the process of creating new DNA through cell division, possibly resulting in errors
Gene Duplication (example)
Errors made during gene duplication for some saltwater fish allowed for greater control of molecules in their cells, allowing them to move into a freshwater niche easily as they can control the level of minerals in their cells
Gene Transfer (number)
3
Gene Transfer (definition)
the unpredictable transfer of genetic information between parent and offspring, resulting in differences between generations
Gene Transfer (example)
Haplodiploid systems of inheritance in bees, referring to males with one set of chromosomes and females with two. Results in sons with 100% of genes in common with father, daughters with 50%
Phenotype (number)
4
Phenotype (definition)
the physical characteristics of an organism, as a result of how environment and genotype interact
Phenotype (example)
Human skintone influenced by parent’s skintone and also where they are geographically (sunlight levels, weather, etc)
Niche Occupation (number)
5
Niche Occupation (definition)
the process of occupying a niche (an organisms relationship with living and non-living things in it’s environment) to prevent competition
Niche Occupation (example)
The crabs and ants on Christmas Island can’t cohabit, so in a situation where there would normally be niche partitioning, this isn’t occurring. Instead, the invasive ants kill the native crabs in an attempt to take over the niche
Most Available Solution (number)
6
Most Available Solution (definition)
a species evolves the trait that is not necessarily the best response to an evolutionary problem, but what is most available in its genome
Most Available Solution (example)
Different rock pocket mice evolved dark fur, but through different genes. They evolved dark fur as a solution to predation, but through different ways depending on what was available for them
Costs & Benefits (number)
7
Costs & Benefits (definition)
whether a trait is selected for depending on the benefits or costs
Costs & Benefits (example)
Descendants of LUCA lost genes necessary for living near hydrothermal vents as they were expanding out to new areas, and it was no longer beneficial to them. Those genes were not necessary, and were possibly restricting their expansion now that they were moving into new niches
Co-Option (number)
8
Co-Option (definition)
an existing trait evolves a new function
Co-Option (example)
At the split between jawless and jawed fish, the now-jawed fish had a mutation that altered the pattern of 1st-gill development, resulting in what are now called jaws. They used what used to be a gill and co-opted it into becoming something new
