Chapter 21
_______ must be present in a population before natural selection can act upon the population
What is genetic variation?
A change in genetic composition of a population from generation to generation.
What is evolution?
If organisms A, B, and C belong to the same class but to different orders, and if organisms D, E, and F belong to the same order but to different families, which three organisms listed (A, B, C, D, E, and F) would show the greatest degree of structural homology?
What is D, E, and F?
(NOTE: D, E, and F are of the same order - which is a more specific/narrow hierarchy than class)
This feature/molecule was present on Earth when life first evolved.
What is water?
Eukaryotic cells originated through an ancestral archaeal cell engulfing aerobic bacteria and cyanobacteria which resulted in the organelles mitochondria and plastids (chloroplasts). This theory is known as ______
In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the frequency of the allele a is 0.3. ________ is the frequency of individuals that are homozygous for this allele
What is 0.09?
Humans have produced different breeds of Canis familiaris (dogs) by breeding based on desired traits. This is an example of _____ process.
What is artificial selection?
In a comparison of birds and mammals, the condition of having four limbs is considered this type of character.
What is an ancestral character?
The majority of a bacterium's genetic information is located in this location.
What is the nucleoid?
Multicellular colonies of plant cells adhere to each other primarily by _____, whereas multicellular colonies of animal cells are typically help together by _______.
What are cell walls and proteins?
______, ______, and _____ are fundamental mechanisms that drive changes in allelic frequencies and shape evolution.
What are natural selection, genetic drift, and gene flow?
In terms of homologous structures between closely related and distantly related organisms - if two modern organisms are distantly related in an evolutionary sense, then one should expect ___
That these two modern organisms share fewer homologous structures than two more closely related organisms
This term associated with phylogenetic trees represents groups of organisms that share an immediate common ancestor
What are sister taxa?
This process involves a bacterium picking up a piece of DNA from its environment and incorporating the DNA into its own genome.
What is transformation?
These are the 4 supergroups of eukaryotes which include all eukaryotic life.
What are archaeplastida, SAR, Excavata, and Unikonta
Adaptive evolution, where populations of organisms acquire traits that enhance survival and reproduction, occurs because of _________
What is natural selection?
Members of two different species possess similar-looking structures that they use in a similar fashion to perform the same function. This implies that the structures ________ the function and the organisms _______ ancestry (answer with how these structures are related functionally and how the organisms are related ancestrally)
This implies that the structures share a common function, but the organisms do not share a common ancestry
The observation that genetic mutations in the genome appear to accumulate at constant rates across a wide diversity of taxa led to the development of ______
What are molecular clocks?
These are the three types of horizontal gene transfer mechanisms in which prokaryotic genomes diversify.
The organism, Plasmodium, is a protist parasite which causes this disease
Human populations living at high altitudes, with low oxygen availability, for generations experiences natural selection related to their environment. In Tibet (Asia), for example, people have larger lungs. This trait in people who live in high altitudes illustrates _____
What is adaptive evolution?
Darwin's observations of the Galapagos Islands finches' various beaks and behaviors could be explained by adaptations which are the result of this process
What is natural selection?
_________ gene transfer confuses phylogenetic analysis, particularly in prokaryotic organisms
What is Horizontal?
Rhizobia are soil bacteria which infect the roots of plants such as peas o convert atmospheric nitrogen into a form the peas can use (like ammonia). The Rhizobia receive organic acids from the plant that they use as a source of carbon and energy. The ecological relationship described here is___
What is mutualism?
Genome sequence comparisons between this protist and animals provide evidence that this protist is closely related to animals.
What is choanoflagellate?