487 Created by Master Student Biology Practice Test #7 1 / 40 Structure where most digestion and absorption of nutrients occurs Small intestine Large intestine Stomach Esophagus Mouth A Most digestion and absorption occur in the small intestine. A very small amount of digestion (starch only) takes place in the mouth, and a very small amount of digestion takes place in the stomach (acid hydrolysis of food and some protein digestion). As with Questions 7-9, Questions 10-12 require the same type of knowledge-memorization of basic facts. 2 / 40 This can result in stabilizing selection in a population. Founder effect Heterozygote advantage Population bottleneck Random mating Reproductive isolation Heterozygote advantage confers a fitness advantage on heterozygous individuals. The amount of variance for the phenotype will decrease, though the mean will stay the same. On a graph of frequency vs. phenotype, this is depicted as a narrowing of the curve. 3 / 40 A lake filled with algae that are choking out aquatic plants and fish is likely experiencing which process? Succession Eutrophication Denitrification Carbon fixation Acid rain runoff Algae are photosynthetic organisms that thrive in conditions of abundant nutrients such as nitrogen. A eutrophic lake is one that contains an overabundance of nutrients. 4 / 40 Which of the following is positively associated with biodiversity? I. Diversity of ecosystems II. Genetic variation within species III. Species diversity within communities III only I and II only I and III only II and III only I, II, and III 0 5 / 40 All of the following organs serve a role in excreting metabolic wastes EXCEPT the skin large intestine lungs liver kidney The large intestine eliminates digestive wastes rather than metabolic wastes. 6 / 40 Arthropods can be characterized by all of the following EXCEPT a hard exoskeleton a water vascular system jointed appendages molting segmented body B Choices A, C, D, and E all describe characteristics of the phylum arthropoda. A water vascular system is a characteristic of the phylum echinodermata, the "spiny skinned" animals such as sea stars and sea urchins. Their water vascular system ends in tube feet that play a role in locomotion and feeding. Don't forget your LEAST/EXCEPT/NOT technique of circling the word "EXCEPT" and drawing a vertical line through the answer choices to help you remember to choose the incorrect statement. 7 / 40 The field of ecology that studies how species are distributed over the Earth is called ethology paleontology biogeography community ecology conservation ecology Biogeography is the study of the distribution of species over the globe. 8 / 40 Which of the following leads to a replacement of the plant community in an ecosystem undergoing succession? Pollution Herbivory Parasitism Abiotic factors Intraspecific competition In ecological succession, a plant community is replaced by a subsequent plant community. This occurs because the plants in the original community alter abiotic factors, such as shade and soil nutrients, making the ecosystem more suitable for the seeds of different plant species. 9 / 40 Which of these would a researcher test the blood for to determine if a person has been infected with a virus in the past? Antigens Antibodies Macrophages Pathogens Natural killer cells Antigens or immunoglobulins produced by B and T cells are specific and provide a "memory" that helps to fight previously encountered pathogens, or infectious organisms. Antigens, produced by pathogens, would not linger in the blood. Macrophages and natural killer cells are part of the innate immune system and would not be specific to a particular virus. 10 / 40 Northern areas, characterized by permafrost, extremely cold temperatures, and few trees Tundra Taiga Tropical rain forest Deciduous forest Desert A These are the characteristics of tundra. 11 / 40 Location of cellular respiration in prokaryotes Mitochondria Cytoplasm Pyruvate Lactic acid Glucose B Prokaryotes (Domains Bacteria and Archaea) have no membrane-bound organelles, so all reactions and processes occur in the cytoplasm. You should have been able to eliminate choices C, D, and E because they did not describe locations. 12 / 40 A horse has 64 chromosomes, while a zebra has 4 In rare cases, it is possible to cause these two species to hybridize, creating offspring that are fertile, with 46 chromosomes fertile, with 55 chromosomes sterile, with 46 chromosomes sterile, with 55 chromosomes sterile, with 64 chromosomes A hybrid of two species with differing chromosomal numbers will be incapable of forming its own gametes and thus is considered sterile. In order to form a zygote, homologous chromosomes or each gamete must pair. Because zebra gametes will only possess the haploid number of 23 chromosomes and a horse's gamete a haploid number of 32, the resulting zygote will have 54 chromosomes. 13 / 40 Nitrogen-fixing bacteria are most likely found in which environment? Stomach of a reptile Lower epidermis of leaves Gills of freshwater fish Large intestine of humans Root systems of plants A common mutualism between plants and bacteria occurs in root systems, which host microorganisms that make limiting nutrients, such as nitrogen, available to the plants. 14 / 40 Which of these relationships results in harm to one of the species involved? I. Commensalism II. Predation III. Herbivory I only III only I and II II and III I, II, and III 0 15 / 40 Which of the following is/are true for a resting human? I. Systolic blood pressure of 180 mm Hg II. Heart rate of 60-80 beats per minute III. Body temperature of 37oC I only II only I and II II and III only I, II, and III 0 16 / 40 Hemoglobin is a protein in red blood cells that binds and carries oxygen and some carbon dioxide. Its affinity for oxygen changes as blood travels from the lungs to the body tissues and back to the lungs again. One could expect hemoglobin to have a high carbon dioxide affinity in the lungs and a low oxygen affinity in the tissues a low carbon dioxide affinity in the lungs and a high oxygen affinity in the tissues a high oxygen affinity in the lungs and a low oxygen affinity in the tissues a low oxygen affinity in the lungs and a high oxygen affinity in the tissues a high oxygen affinity in the lungs and a high carbon dioxide affinity in the lungs C The job of the blood is to carry oxygen from the lungs, where it is plentiful, to the tissues, where it is not. Thus hemoglobin should have a high affinity for oxygen in the lungs so it can bind oxygen (choices A, B, and D could be eliminated) and a low oxygen affinity in the tissues (so it can release the oxygen where it is needed). The reverse is true for carbon dioxide. Hemoglobin has a high carbon dioxide affinity in the tissues and a low carbon dioxide affinity in the lungs. 17 / 40 This cell type is involved in nonspecific immunity. B cell Fibrinogen Pathogen Phagocyte T cell Phagocytes engulf and destroy both foreign cells and damaged or nonfunctional cells in the blood. They do not specifically target an infecting agent. 18 / 40 Which answer choice matches the functions listed below to the correct RNA types? I. Interprets a codon as an amino acid II. Binds to a gene transcript III. Contains information for assembling a protein I. mRNA; II. rRNA; III. tRNA I. mRNA; II. tRNA; III. rRNA I. rRNA; II. mRNA; III. tRNA I. tRNA; II. mRNA; III. rRNA I. tRNA; II. rRNA; III. mRNA 0 19 / 40 Ground tissue with no specialized function Xylem Phloem Cambium Bark Pith Pith is a source of unspecialized ground tissue that adds structure to a stem at the very center. 20 / 40 This is required for speciation to occur. Founder effect Heterozygote advantage Population bottleneck Random mating Reproductive isolation Speciation requires that two populations be reproductively isolated from each other, allowing natural selection to act independently on each. 21 / 40 A solute cannot move into a cell by crossing the phospholipid bilayer of the membrane. It can, however, enter through a membrane protein. The fact that solute molecules are entering the cell MOST LIKELY indicates that energy is being expended by the cell the solute is moving against its concentration gradient the solute molecules are hydrophilic the cell is in a hypotonic solution solute concentration is higher inside than outside the cell The fact that solute molecules are entering a cell via a membrane protein does not necessarily mean that the cell is expending energy (active transport), that the solute is moving against its concentration gradient (which requires energy), or that the solute concentration is greater inside the cell than outside (implying that the solute is moving against its concentration gradient). If the cell were in a hypotonic solution, solutes would tend to move out of the cell while water moved into it. Facilitated diffusion uses membrane protein to allow polar, hydrophilic molecules or ions into the cell. These solutes cannot pass through the nonpolar, hydrophobic inner layer of the cell membrane. 22 / 40 Plants that have true roots, stems, and leaves, as well as flowers and seeds enclosed in fruit, are classified as bryophytes tracheophytes gymnosperms angiosperms endosperms D Flowering plants are angiosperms. Gymnosperms are conifers (naked seed plants; C is wrong), bryophytes are mosses (A is wrong), and tracheophytes are non-seed producing plants (ferns; B is wrong). "Endosperm" is not a classification for plants. 23 / 40 A population that prevents other populations from using a particular limited resource Predation Commensalism Interspecific competition Mutualism Parasitism C For a population to prevent another population from using a resource, the first population must be a better competitor. Choice C is the only one that deals with competition. 24 / 40 The net equation for photosynthesis is C6H12O6 + 6O2→6CO2 + 6H2O 6CO2 + 6H2O→C6H12O6 + 6O2 C6H12O6 + 6H2O→6CO2 + 6O2H 6CO2 + 6O2→C6H12O6 + 6H2O 6CO2 + C6H12O6→6O2 + 6H2O Photosynthesis produces glucose and oxygen from carbon dioxide and water. 25 / 40 Which of these cell structures contains one or more membranes? I. Ribosome II. Plasma membrane III. Endoplasmic reticulum IV. Golgi body II only IV only I and II I, II, and III II, III, and IV The ER, plasma membrane, and Golgi body of a eukaryotic cell consist of membrane composed of a phospholipid bilayer. In contrast, the ribosome is not a membrane-bound organelle. 26 / 40 In a system where only two genes are responsible for determining skin pigmentation, a woman is heterozygous for one gene and homozygous for the other. The woman herself only exhibits the homozygous trait. This pattern of expression is known as epistasis X-linkage pleiotropy codominance simple dominance When more than one gene affects a trait but only one is expressed, this is called epistasis because one gene "stands over" another. 27 / 40 Deoxygenated blood is pumped to the lungs through which parts of the heart? 1, 2, and 6 1, 2, and 7 2, 4, and 6 3, 4, and 5 3, 4, and 8 Deoxygenated blood enters the right atrium of the heart (1) through each vena cava (7). From these, it is pumped to the right ventricle and through the pulmonary arteries, to the lungs. 28 / 40 Which of these describes a difference between monocots and dicots? Monocot embryos form two leaves; dicot embryos form a single leaf. Monocot flowers may consist of five petals; dicot flowers may consist of six petals. Monocot leaves have a branching network of veins; dicot leaves have parallel veins. Monocot roots consist of many small roots growing from a taproot; dicot roots lack a taproot. Monocot vascular tissue is arranged randomly in the stem; dicot vascular tissue is arranged in a ring. Monocot vascular tissue is arranged randomly in the stem, while dicot vascular tissue is arranged in a ring. All other answer choices have characteristics reversed. 29 / 40 Which of the following are in order of least complex to most complex, in terms of the amount of genetic information they carry? I. Chromosome II. Base pair III. Codon IV. Gene I → II → III → IV II → III → I → IV III → II → I → IV II → III → IV → I II → IV → II → I 0 30 / 40 Stage of meiosis during which recombination of genetic material occurs Anaphase II Metaphase I Prophase II Metaphase II Prophase I E Recombination occurs when the homologous chromosomes are paired and crossing over can take place. This occurs during prophase I of meiosis. Remember that recombination occurs during prophase, and this would help you eliminate choices A, B, and D. 31 / 40 Which refers to the degree to which a phenotype is determined by genetic variation in a population? Fitness Heritability Limited environmental resources Overproduction of offspring Phenotypic variation The extent to which a phenotype is determined by differences in alleles in a population is referred to as heritability. Natural hair color is a highly heritable trait, whereas the number of legs has almost no heritability because there is little genetic variation for this phenotype in the population. 32 / 40 At which stage in meiosis are sister chromatids of each chromosome identical? I. Beginning of prophase I II. Beginning of metaphase I III. End of telophase I I only II only III only I and II II and III 0 33 / 40 A barren, rocky community near a lake has virtually no vegetation or animal life. After a period of approximately 75 years, the community boasts a wide variety of flora and fauna, including deciduous trees, deer, and raccoon. The stable community of deciduous trees and animals is known as the final community climax community apex community summit community composite community B The climax community is the final, stable community in succession. The key word here is "stable." That should tip you off that this is the end of the process, or the " climax." 34 / 40 During which phase of mitosis do the centromeres split? Anaphase Cytokinesis Metaphase Prophase Telophase The centromeres joining sister chromatids split in anaphase. The chromosomes are then pulled to opposite poles. 35 / 40 At which stage in meiosis are sister chromatids of each chromosome identical? I. Beginning of prophase I II. Beginning of metaphase I III. End of telophase I I only II only III only I and II II and III 0 36 / 40 Which processes remove nitrogen from the atmosphere? I. Fertilizer production II. Eutrophication III. Nitrogen fixation IV. Denitrification I and II I and III I and IV II and III II and IV 0 37 / 40 Myriophyllum spicatum, or water milfoil, native to Eurasia, is an aggressive, invasive aquatic plant in North America. All of the following are reasons this species is successful as an invasive species EXCEPT milfoil evolved from North American plant species milfoil has few natural predators in a nonnative environment milfoil has few natural competitors among North American plant species milfoil is a hardy plant capable of succeeding in harsher environments milfoil is resistant to many native diseases that are adapted to native plant species Because its evolutionary history is elsewhere, milfoil has adapted to an environment that lacks the natural predators and pathogens of North America, making it less susceptible to them and therefore more competitive than native plants in North America. 38 / 40 Which of the following is required for speciation to take place? Increased genetic variation Random mating Reduced gene flow Geographic isolation Mutation Only a reduction in gene flow is absolutely required for speciation to take place. Populations cannot evolve independently if their gene pools are shared. 39 / 40 Which of these correctly matches each structure to the germ layer from which it arises? I. Femur II. Brainstem III. Lungs I = endoderm; II = ectoderm; III = mesoderm I = endoderm; II = mesoderm; III = ectoderm I = ectoderm; II = endoderm; III = mesoderm I = mesoderm; II = endoderm; III = ectoderm I = mesoderm; II = ectoderm; III = endoderm 0 40 / 40 A genetic mutation results in a DNA sequence that continues to synthesize the same protein, at the same rate as a nonmutated sequence. This mutation would be BEST classified as a deletion insertion missense mutation nonsense mutation silent mutation A silent mutation is not phenotypically visible because the protein product remains unchanged. Your score is The average score is 55% LinkedIn Facebook Twitter VKontakte 0% Restart quiz Previous Quiz Next Quiz
