Genetics & DNA Technology

Genetics & DNA Technology 65. Gregor Mendel crossed a true-breeding tall plant (TT) with a true-breeding short plant (tt). What are the possible phenotypes for the offspring? A. All tall B. All short C. Ratio of 1 tall : 1 short D. Ratio of 2 tall : 1 short

Genetics & DNA Technology 66. A population of crabs living on a sandy beach exhibits three colors: dark brown, light brown, and speckled. The genotypes for these colors are BB for dark brown, bb for light brown, and Bb for speckled. If a dark brown crab were crossed with a light brown crab, what would be the probable phenotypic ratio of their offspring? A. All speckled B. All dark brown C. 3 dark brown : 1 light brown D. 1 dark brown : 2 speckled : 1 light brown

Genetics & DNA Technology 67. In snap peas, yellow flowers (Y) are dominant to white flowers (y). In the cross YY × Yy, what would be the genotypic ratio of the F1 generation? A 1:1 B 1:2 C 1:3 D 3:1

Genetics & DNA Technology 68. A population of crabs living on a sandy beach exhibits three colors: dark brown, light brown, and speckled, as shown above. The genotypes for these colors are BB for dark brown, bb for light brown, and Bb for speckled. The speckled crabs blend in extremely well with the color of the sand on the beach. The pattern appears to provide the speckled crabs with some protection from predatory birds. Which of the following conclusions can be drawn from the information above? A. Only the speckled crabs will survive, and all of their offspring will be speckled. B. The allele for light brown color will be lost because of predatory birds eating light brown crabs. C. The allele for dark brown color will be lost because of predatory birds eating dark brown crabs. D. Both the light brown and dark brown alleles will continue to be passed on in the crab population.

Genetics & DNA Technology 69. The technique known as chromosome painting is the result of scientific research. Scientists use chromosome painting to mark the locations of genes on human chromosomes with fluorescent tags. It is also possible to apply this technique to the chromosomes of many different species. Chromosome painting allows for which of the following? F. A comparison of the genomes of different species G. The sequencing of proteins from many species H. An increase in mutations in many species J. The extraction of amino acids from different species

Genetics & DNA Technology 70. If several pea plants with the genotype TTYyare crossed with pea plants with the genotype Ttyy, what percentage of the offspring will be expected to have the TTYyallele combination? A. 25% B. 40% C. 50% D. 75%

Genetics & DNA Technology 71. In cocker spaniels the allele for a black coat color (B) is dominant over the allele for a brown coat color (b). If a brown cocker spaniel is crossed with a heterozygous black cocker spaniel, which of the following genotypic ratios can be expected? F. 0 BB: 2 Bb: 2 bb G. 1 BB: 2 Bb: 1 bb H. 2 BB: 0 Bb: 2 bb J. 2 BB: 1 Bb: 0 bb

Genetics & DNA Technology 72. The processes of deletion, insertion, and substitution can alter genes in a skin cell. The altered genes will most likely be passed on to A. sperm cells B. egg cells C. every cell that develops from that skin cell D. only a few of the cells that develop from that skin cell

Genetics & DNA Technology 73. The fact that a strain of yeast with a certain defective gene can use the human version of the gene to repair itself is evidence that yeast and humans — A. depend on the same food supply B. share a genetic code C. both have eukaryotic cells D. have identical genomes

Genetics & DNA Technology 74. The diagram below represents a segment of a gene on two chromosomes. The change in the gene sequence is an example of A. an insertion B. a deletion C. a substitution D. a replication

Evolution 75. After examining the fossil record, scientists have determined that scorpions today are much smaller than their extinct ancestors. For example, Jaekelopterusrhenaniae, a giant scorpion species that lived 255 million to 460 million years ago, was 2.5 meters long. Which of the following conclusions is supported by this information? F. Scorpions living today have increased their numbers since they first appeared. G. Scorpions in the fossil record are smaller than their descendants are. H. Scorpions have changed as a result of natural selection. J. Scorpions do not appear in their original state in the fossil record.

Evolution 76. A harmless scarlet king snake and a venomous eastern coral snake have similar band patterns, as shown below. For the scarlet king snake, the adaptation of having a banding pattern like the eastern coral snake’s is known as mimicry. The outcome of this adaptation in the scarlet king snake is to— A. make it easier for the scarlet king snake to attract prey B. make it easier for the scarlet king snake to interbreed with the other snake C. allow the scarlet king snake to blend in with its environment D. protect the scarlet king snake from predators

Evolution 77. Gene flow is one force that can cause evolutionary change. Which example best illustrates gene flow? A. A flock of migrating geese enters into the territory of another flock and begins interbreeding. B. A flock of geese becomes isolated on an island, and over time, the population begins to exhibit new characteristics. C. Some individuals in a flock of geese have genes that are more advantageous, and over time, the numbers of these geese increase. D. A flock of migrating geese loses its way to its wintering grounds, leaving other geese without competition for resources and enabling those geese to produce more offspring.

Evolution 78. Some organisms have genes that improve their ability to survive and reproduce. If the genes also help their offspring survive and reproduce, then which of the following will most likely increase? F. The frequency of the genes in one individual G. The frequency of the genes in the population H. The number of genes in one chromosome J. The number of genes in the species

Evolution 79. Which finches would be most like the ancestral finch? A. large ground finches C. warbler finches B. cactus finches D. large tree finches 80. Present-day cactus finches are a type of A. tree finch C. warbler finch B. ground finch D. ancestral finch

Evolution 81. When Darwin first proposed his theory of evolution by natural selection, the field of genetics did not yet exist. In what way does genetic science now contribute to the study of evolution? A. Scientists can create organisms that were extinct using DNA from fossils and better understand how they evolved. B. Scientists can use genetic engineering to carry out the process of evolution over just months instead of millions of years. C. Scientists can compare the DNA from fossils in rock to determine evolutionary relationships among extinct species. D. Scientists can determine evolutionary relationships among living species by comparing amino acid and DNA sequences.

Evolution 82. Zoogeographic regions are characterized by the presence of specific groups of animals. These regions are determined by the taxonomic or phylogenetic relationships of animals. The map shows the zoogeographic regions proposed by the naturalist Alfred Russel Wallace in 1876. The similarities of organisms in which two areas numbered above provide the best evidence for common ancestry between the organisms in both locations? A. 1 and 2 C. 5 and 6 B. 3 and 4 D. 7 and 8

Evolution 83. The limbs of several organisms are shown in the illustrations below. Scientists sometimes compare the limbs of these organisms to look for evidence of common ancestry. These limbs provide evidence of common ancestry because they — F. have the same basic structure G. perform the same function H. are the same size J. are parts of mammals

Evolution 84. A paleontologist is studying the distribution of ancient gastropods using the fossil record. What can she infer about the age of the fossils based on their location in the fossil record? A. Fossils found in lower layers are generally younger than those found in upper layers. B. Fossils found in lower layers are generally older than those found in upper layers. C. Fossils found in lower layers are too old to undergo Carbon-14 dating, and are therefore more than 60,000 years old. D. Fossils found in consecutive layers always are the same age, based on radiometric dating.

Evolution 85. Genetic drift states that the random effects of everyday life can cause differences in the survival and reproduction of individuals. What is one effect of genetic drift on evolution? A. It produces only the traits in a population that are best adapted to the environment. B. It can cause an unusual amount of genetic variation within a single population of a species. C. It can cause a population’s allele frequencies to stay in genetic equilibrium. D. It can cause certain traits in a population to increase in frequency even if those traits are not the ones that are best adapted to the environment.

Classification 86. Having a standard taxonomic system benefits the scientific community by allowing scientists from all over the world to do which of the following? A. Have a common system for the classification of locations containing fossils B. Use a similar system to classify the impact of removing species from ecosystems C. Have a common understanding in the classification of organisms D. Understand how other scientists classify predator– prey relationships

Classification 87. A student collected the animal shown below on a field trip. The student used a dichotomous key and a microscope to classify the animal. How should this animal be classified? A. Arthropoda B. Annelida C. Mollusca D. Platyhelminthes

Classification 88. Arthropods are joint-legged animals. Spiders, crabs, pill bugs, centipedes, and millipedes are examples of the many types of arthropods. Which of these arthropods are most closely related? F. Arthropods of the same family G. Arthropods of the same class H. Arthropods of the same genus J. Arthropods of the same species

Classification 89. The diagram shows taxonomic groups and a major distinguishing characteristic of all but two of them. Which characteristics will be used to complete the chart?

Classification 90. The Venn diagram above compares the two kingdoms Archaebacteria and Eubacteria. Which of the following scientific explanations supports the division of archaea, or archaebacteria, and bacteria into two different domains? A. Archaea cause disease, but bacteria do not. B. Bacteria have a nucleus, but archaea do not. C. Archaea are single-celled, but bacteria often have more than one cell. D. Archaea and bacteria exhibit differences in cell walls, cell membranes, and gene structure.

Classification 91. In the Linnaean system of classification, organisms are grouped in successive levels of hierarchy based on similarities in their form and structure. The diagram models the eight basic levels of the modern Linnaean system. Which level of the Linnaean system does level 8 represent in the figure? A. Class B. Domain C. Family D. Species

Classification 92. The diagram above shows the evolutionary relationships among five animals. What major characteristic is the same for all five animals? A. All are carnivores. B. All have backbones. C. All spend their entire lives on land. D. All maintain a constant body temperature.

Classification 93. Which series represents the correct order of levels of classification, from broadest to narrowest? A. Domain, kingdom, phylum, order, class, family, genus, species B. Domain, kingdom, phylum, class, order, family, genus, species C. Kingdom, phylum, domain, order, class, family, genus, species D. Species, genus, family, class, order, phylum, kingdom, domain

Classification 94. The dichotomous key below provides a way to classify some animals into groups according to their physical characteristics.

Classification 95. An organism is made up of many cells, similar to the cell shown in the diagram below. What can you conclude about the organism? A. It is a type of prokaryote. B. It belongs to the domain Archaea. C. It belongs to the domain Eukarya. D. It belongs to the kingdom Protista.

Genetics & DNA Technology