Evolutionary Framework of Biology - Exam 1

Question 1

Theory of Evolution

Answer 1

Fact #1: Reproductive rates of organisms are high enough that if mortality rates did not balance them, the population would quickly become enormous.

Fact #2: All organisms are variable and variation is inherited by offspring

Conclusion/Theory: the differences among individuals affect their survival and reproduction rates, the better the survival and reproduction rate of a trait, the more likely it will be passed down.

Question 2

Evidence in support of the theory of evolution

Answer 2

Fossil record, artificial selection, and phylogenetic similarities

Question 3

Fossil record

Answer 3

1. Progression of forms
2. Dating methods
3. Extinctions

Question 4

Progression of forms

Answer 4

1. gradualism- smooth gradual evolutionary change without any breaks, can be represented by a linear sloping line
2. gaps- breaks in evolutionary history where there are missing intermediate fossil forms between the intital and final fossil forms (example: Cetaceans)
3. punctuates equilibrium- accounts for adaptive radiation

Question 5

Dating methods

Answer 5

radiometric dating, carbon dating

Question 6

Extinctions

Answer 6

Extinctions lead to adaptive radiation because ecological niches are opened up to organisms who otherwise could not inhabit them.

Question 7

artificial selection

Answer 7

Breeding organisms with specific traits in order to produce offspring with identical traits. Example: dogs come from wolves but have been bred for specific traits leading to a variety of different phenotypes and even leading to completely distinct breeds.

Question 8

Phylogenetic similarities

Answer 8

1. Morphology/anatomy
2. Vestigial organs
3. Comparative embryology
4. Comparative biochemistry/genetics

Question 9

Morphology/anatomy

Answer 9

structural features common between species with a common ancestor. Example: homologous limbs, most animals’ arms have the same bones but certain bones are larger than others due to selection amongst members of that species.

Question 10

Vestigial organs

Answer 10

Organs that are historical hangers-on meaning they used to have a funstion within that organism but no longer do. Example: human appendices.

Question 11

Intelligence of evolution

Answer 11

Not all evolution is maximally intelligent: Human throat, panda thumb

Question 12

Comparative Embryology

Answer 12

the existence of similarities between embryos of animals with a common ancestor. Example: Human and chicken embryo, “ontogeny recapitulates phylogeny”

Question 13

Comparative genetics

Answer 13

genetic code is the same from bacteria to humans (DNA and RNA)

Question 14

Phylogenetic tree

Answer 14

A diagram that shows differences and similarities between organisms based on mitochondrial rRNA sequences

Question 15

Random processes that occur to make genetic diversity possible

Answer 15

mutation and sexual recombination

Question 16

non-random processes that contribute to fitness

Answer 16

natural selection

Question 17

model systems

Answer 17

model systems can be used to predict behavior or reaction for some conserved genes in other organisms. Example: experiments on yeast, mice, and fruit flies to find reactions in humans.