BSC 108 test 3 Exam Questions With Complete Solutions

Formation of a new species is called - ANS speciation As a mechanism of evolution, natural selection can be most closely equated with - ANS unequal reproductive success What is NOT an example of natural selection? - ANS On a tree, leaves that grow in the shade are larger than those that grow in the sun Which of the following pairs of anatomical structures are homologous? - ANS bat wing and human arm A gene pool is - ANS All of the alleles in a population The smallest biological unit that can evolve over time is - ANS a population Genetic drift is genetic exchange with another population. - ANS false Two different species can evolve independently but acquire the same traits as adaptations to similar environments - ANS true Two species of birds live in the same tree and compete for the same food on the tree. What will be the eventual outcome? - ANS The species that is able to obtain the most resources will survive while the other will find another food source or become extinct Which statement about natural selection is MOST correct? - ANS Well-adapted individuals leave more offspring than poorly adapted individuals. Describe the process of translation. - ANS mRNA carries a genetic message from the nucleus to a ribosome and attaches. tRNA carries amino acids from the cytoplasm to the ribosome. The anticodon of a tRNA molecule binds to the codon of the mRNA molecule and the amino acid attaches to the growing chain of amino acids, forming a polypeptide. The end result is a protein whose sequence of amino acids is dictated by the codon sequence of the mRNA. Describe the process of DNA replication - ANS One parent molecule that has two complementary strands separates at the origin of replication. Synthesis of two new complementary strands occurs in the replication bubble using each strand as a template to make a new strand. The replication bubbles merge as DNA replication progresses in both directions at the replication forks. When complete, each of the two daughter molecules will be composed of one "old" strand and one "new" strand If one strand of DNA had a sequence of CTCTAGTCA, what would be the sequence of the other strand? - ANS GAGATCAGT Give the general steps in conducting genetic engineering experiments. - ANS The basic steps in a genetic engineering experiment are to first cleave the DNA to isolate the gene of interest, the second step is to produce the recombinant DNA, the third step is to clone and reproduce the DNA in cells and lastly screening to locate cells that carry the desired gene Give two examples of how has genetic engineering affect agriculture - ANS Genetically engineered agricultural plants have increased resistance to pests, herbicides, cold, and drought, enhanced nutritional value, and greater yields There could be a food chain without decomposers consisting of producers, herbivores, omnivores, and carnivores - ANS false Energy from the sun is converted into chemical energy by - ANS producers What is the difference between primary and secondary succession? - ANS Secondary succession occurs in land with existing soil while primary succession does not What are the three main types of interspecific interactions? - ANS predation, competition, and mutualism