BIO 201 EXAM 4 | ANATOMY & PHYSIOLOGY 1 | HIGH-YIELD ACTUAL QUESTIONS & 100% VERIFIED ANSWERS

BIO 201 EXAM 4 | ANATOMY & PHYSIOLOGY I | HIGH-YIELD ACTUAL QUESTIONS & 100% VERIFIED ANSWERS 1. According to current scientific thinking, true multicellular organisms A. cannot be traced to existing or fossil intermediate stages; thus, there is no current scientific theory for the process that generated multicellular organisms from unicellular ancestors B. descend from several different kinds of unicellular protists, which became multicellular through specialization and cooperation among cells within a colony C. are all descended from a single colonial protist ancestor D. formed through the fusion of several separate species of unicellular protists, who carried out different complementary functions within the evolving organism Correct Answer: B Rationale: Current scientific evidence supports that multicellular organisms descended from several different kinds of unicellular protists. Through specialization and cooperation among cells within colonies, these protists evolved into complex multicellular forms through multiple independent evolutionary events. ________________________________________ 2. The ______ are heterotrophic protists; ______ are photoautotrophic protists. A. Protozoans, plants B. Parasites, protozoans C. Protozoans, algae D. Mixotrophs, protozoans Correct Answer: C Rationale: Protozoans are heterotrophic protists that obtain nutrients by consuming organic matter, while algae are photoautotrophic protists that produce their own food through photosynthesis. Plants are not protists, and mixotrophs can use both methods. ________________________________________ 3. Rod shaped bacteria are called A. cocci B. spirochetes C. bacilli D. vibrios Correct Answer: C Rationale: Bacilli are rod-shaped bacteria. Cocci are spherical, spirochetes are spiral-shaped, and vibrios are comma-shaped bacteria. This classification is based on bacterial morphology. ________________________________________ 4. Eukaryotes are ______ prokaryotes. A. more ancient than B. more numerous than C. dependent upon D. more widespread than Correct Answer: C Rationale: Eukaryotes are dependent upon prokaryotes in many ways, including the endosymbiotic theory which suggests that mitochondria and chloroplasts evolved from prokaryotic organisms. Prokaryotes are actually more ancient, more numerous, and more widespread than eukaryotes. ________________________________________ 5. There is a good chance you will eat carrageenan today and that you will eat nori at some point in your life, if you haven't already. In either case, you will be eating a product of A. brown algae B. green algae C. diatoms D. red algae Correct Answer: D Rationale: Carrageenan is a thickening agent extracted from red algae, and nori is the dried seaweed used in sushi that comes from red algae (specifically Porphyra species). Both are products of red algae. ________________________________________ 6. Cyanobacteria A. are prokaryotes with plantlike oxygen generating photosynthesis B. are eukaryotes and are the earliest type of algae C. are chemoautotrophs D. are photosynthetic archaea Correct Answer: A Rationale: Cyanobacteria are prokaryotic organisms that perform oxygenic photosynthesis similar to plants. They are not eukaryotes, chemoautotrophs, or archaea. They were instrumental in oxygenating Earth's atmosphere. ________________________________________ 7. Intestinal gas is evidence of active ______ in one's digestive tract. A. thermophiles B. methanogens C. halophiles D. pathogens Correct Answer: B Rationale: Methanogens are archaea that produce methane gas as a byproduct of their metabolism in anaerobic environments like the digestive tract. Intestinal gas (primarily methane and hydrogen) indicates active methanogenic archaea in the gut microbiome. ________________________________________ 8. Which of the following is NOT a characteristic of all living organisms? A. Reproduction B. Response to stimuli C. Photosynthesis D. Metabolism Correct Answer: C Rationale: Photosynthesis is not a characteristic of all living organisms; it is specific to photoautotrophs like plants, algae, and cyanobacteria. All living organisms do reproduce, respond to stimuli, and have metabolism. ________________________________________ 9. The endosymbiotic theory proposes that mitochondria and chloroplasts evolved from A. viruses that infected ancient cells B. free-living prokaryotes that were engulfed by larger cells C. nuclei that split off from the main cell D. spontaneous generation within the cell Correct Answer: B Rationale: The endosymbiotic theory suggests that mitochondria and chloroplasts originated as free-living prokaryotes that were engulfed by larger ancestral eukaryotic cells. They established a symbiotic relationship and eventually became permanent organelles.