PCB4674 Exam 1
Which of the following statements about whale evolution is true? - CORRECT ANSWER - [ANSWER] The fossil record provides evidence about the timing of certain events in whale evolution Which of the following sources of data can be used to study evolution? - CORRECT ANSWER- **[ANSWER] Freq. of traits in pop.s • Morphological data from fossil organisms • DNA sequence data** Which statement characterizes good scientific theories? - CORRECT ANSWER - [ANSWER] They should organize facts and lead to testable predictions.Linnaeus' classification system functions well for living organisms. A little-known fact is that he attempted to apply the same system to rocks and minerals. This has fallen out of use. Why might this be the case? - CORRECT ANSWER - [ANSWER] The fact that rocks and minerals do not evolve means there is no evident hierarchy of relatedness Thomas Malthus' use of mathematical description of the changes in human population size explained - CORRECT ANSWER - [ANSWER] Why all organisms's face a "struggle for existence" The earliest animal fossils appear similar to modern day - CORRECT ANSWER - [ANSWER] Sponges Nearly all currently existing animal lineages evolved during which period? - CORRECT ANSWER- [ANSWER] Cambrian Minik Rosing and Robert Frei have argued that life likely existed as far back as 3.7 billion years
ago. They base this claim on: - CORRECT ANSWER - [ANSWER] The presence of
biomarkers in rocks of that age
Tetrapods include: - CORRECT ANSWER - **[ANSWER]
• Organisms descended from ancestors with four limbs • Birds • Whales** The Edicaran fauna includes - CORRECT ANSWER - [ANSWER] Organisms that are not clearly related to any currently existing lineages 1 / 2
Male pipefish have a brood pouch in which they carry and protect developing embryos. The gene patristacin plays a major role in the formation and function of the pouch. An evolutionary analysis revealed that patristacin is involved in liver and kidney function in all other fish (other
male fish do not produce a brood pouch). This provides an example of: - CORRECT
ANSWER- [ANSWER] Co-option DNA methylation - CORRECT ANSWER - [ANSWER] Is a form of transcriptional regulation of gene expression Trans-acting regulator elements - CORRECT ANSWER - **[ANSWER] • Are typically far away from genes they regulate • Include transcription factors**
Which of the following statements are correct: - CORRECT ANSWER - [ANSWER]
microRNAs bind mRNA and block translation
The presence of a mRNA transcript of a gene in a cell means: - CORRECT ANSWER -
[ANSWER] Transcription of the gene has occurred You are studying snails and find that individuals have shells that either coil to the left or to the right. Which of the following is/are the most plausible explanations for this variation? -
CORRECT ANSWER - **[ANSWER]
• Different alleles at a single locus produce the different phenotypes • Individuals are genetically identical but certain environmental conditions trigger production of each coil type** Tasmanian devils once inhabited most of present day Australis, but only an isolated population on the island of Tasmania has survived to present day. Which of the following processes has likely affected Tasmanian devils as a result of this history? - CORRECT ANSWER - [ANSWER] A genetic bottleneck The effectiveness of selection on an allele depends in part on: - CORRECT ANSWER -
**[ANSWER]
• The frequency of the allele • The magnitude of average excess fitness • The average fitness of the population**
Inbreeding: - CORRECT ANSWER - [ANSWER] Increases homozygosity in populations
The residues ("tailings") of mines often contain such high concentrations of toxic metals (e.g.copper, lead) that most plants are unable to grow on them. However, some hard species (e.g.certain grasses) are able to spread from the surrounding uncontaminated soil into such areas.These plants evolve resistance to the toxic metals while their ability to grow on uncontaminated
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