SECTION 14-1 REVIEW BIOGENESIS VOCABULARY REVIEW Define the following terms. 1. biogenesis 2. spontaneous generation 3. vital force MULTIPLE CHOICE Write the correct letter in the blank. 1. One of the observations that led people to think that life could arise from nonliving things was that a. maggots turned into oval cases from which flies eventually emerged. b. fish appeared in ponds that had been dry the previous season. c. large fish developed from smaller fish, which hatched from fish eggs. d. fish grew larger by eating other living things, such as flies. 2. The purpose of the netting in Redi s experiment was to prevent a. maggots from leaving the jar. b. air from leaving the jar. c. adult flies from entering the jar. d. bacteria from entering the jar. 3. In the experimental group in Spallanzani s experiment, the a. broth remained clear. b. flask contained no broth. c. broth was not boiled. d. flask was not sealed. 4. Spallanzani s opponents disagreed with his conclusion that microorganisms from the air contaminated the boiled meat broth. They argued that Spallanzani a. heated the flasks too long, killing the microorganisms in the broth. b. heated the flasks too long, destroying the vital force in the air inside the flasks. c. waited too long before he sealed the flasks after heating them. d. accidentally contaminated the broth when he sealed the flasks. 5. In Pasteur s experiment, the function of the curved neck on the flask was to prevent a. air from entering the body of the flask. b. air from leaving the body of the flask. c. solid particles from entering the body of the flask. d. broth from spilling out of the flask. Modern Biology Study Guide 71
SHORT ANSWER Answer the questions in the space provided. 1. What observations made in the 1600s and 1700s led some people to believe that there was a vital force in the air? 2. Why did Spallanzani boil the broth in his experiment? 3. How did Pasteur s experiment differ from Spallanzani s experiment? 4. How did Pasteur s experiment answer the objections raised by supporters of the vital force hypothesis? 5. Critical Thinking How might the believers in spontaneous generation have disputed Redi s conclusion if Redi had not used a control group? STRUCTURES AND FUNCTIONS The diagrams below illustrate steps in the control and experimental groups of Spallanzani s experiment. In the spaces provided, list the steps in each group in their proper order. A step may be used in more than one group. Broth becomes cloudy. a Flask is sealed. b Broth is boiled. c Broth remains clear. d Flask is open. e Control group Experimental group 72 Section 14-1 Review
SECTION 14-2 REVIEW EARTH S HISTORY VOCABULARY REVIEW Explain the relationship between the terms in each of the following pairs of terms. 1. radioactive isotope, radioactive dating 2. radioactive decay, half-life 3. microsphere, coacervate MULTIPLE CHOICE Write the correct letter in the blank. 1. The age of Earth is estimated to be a. about 700,000 years. b. about 50 million years. 2. Sulfur has an atomic number of 16. Therefore, the isotope sulfur-35 has a. 19 protons and 16 neutrons. b. 35 protons and 16 neutrons. 3. When performing radioactive dating, scientists measure the a. number of protons and neutrons in the nucleus of a radioactive isotope. b. amount of a particular radioactive isotope contained in a material. c. age of a living organism that is exposed to radioactive isotopes. d. rate at which the mass of an object decreases over time. 4. Carbon-14 dating is useful for estimating the age of a. relatively young organic material. b. old rocks. c. about 400 million years. d. more than 4 billion years. c. 16 protons and 19 neutrons. d. 16 protons and 35 neutrons. c. Earth. d. the solar system. 5. Researchers using the technique of Miller and Urey have been able to produce a. amino acids and nucleotides. b. proteins and DNA. c. ATP and mitochondria. d. cell membranes and simple cells. Modern Biology Study Guide 73
SHORT ANSWER Answer the questions in the space provided. 1. Explain how the half-life of a radioactive isotope affects the usefulness of that isotope in dating specific types of rocks. 2. Why do some scientists think that areas protected from the atmosphere might have favored the production of organic compounds on early Earth? 3. Why was the discovery of microspheres and coacervates an important contribution to the understanding of how life might have originated on Earth? 4. Critical Thinking Does radioactive dating with isotopes of uranium and thorium provide an estimate of the beginning, middle, or end of the period of Earth s formation? Explain your answer. STRUCTURES AND FUNCTIONS Use the figure to answer the following question. The graph below represents the radioactive decay of an isotope. If the half-life of thorium-230 is 75,000 years, how old is a rock that contains only 1/16th of its original thorium-230? Show your calculations in the space below. Amount of isotope remaining All 1 2 1 4 1 8 1 16 0 1 2 3 4 5 6 7 Half-lives 74 Section 14-2 Review
SECTION 14-3 REVIEW THE FIRST LIFE-FORMS VOCABULARY REVIEW Define the following terms. 1. ribozyme 2. chemosynthesis 3. cyanobacteria 4. endosymbiosis MULTIPLE CHOICE Write the correct letter in the blank. 1. The idea that life may have started with self-replicating molecules of RNA is based on the observation that RNA can a. take on a great variety of shapes and act as an enzyme. b. link nucleotides together to form proteins. c. create proteins that have the ability to replicate themselves. d. produce ribozymes that have the ability to produce other ribozymes. 2. The first organisms on Earth were probably a. autotrophic, aerobic eukaryotes. b. heterotrophic, aerobic eukaryotes. 3. The main difference between chemosynthetic autotrophs and photosynthetic autotrophs is that only a. photosynthetic autotrophs use CO 2 as a carbon source. b. chemosynthetic autotrophs use CO 2 as a carbon source. c. chemosynthetic autotrophs obtain energy from inorganic molecules. d. photosynthetic autotrophs synthesize organic compounds. 4. An early function of aerobic respiration may have been to c. autotrophic, aerobic prokaryotes. d. heterotrophic, anaerobic prokaryotes. a. increase the amount of oxygen in the upper atmosphere. b. prevent the destruction of essential organic compounds by oxygen. c. provide more oxygen for photosynthesis. d. enable land animals to breathe. 5. The eukaryotic organelle that is thought to have evolved from aerobic prokaryotes is the a. chloroplast. b. nucleus. c. ribosome. d. mitochondrion. Modern Biology Study Guide 75
SHORT ANSWER Answer the questions in the space provided. 1. Explain how early RNA molecules might have been able to respond to natural selection. 2. What role did the appearance of the ozone layer play in the evolution of early life on Earth? 3. Name three characteristics of mitochondria and chloroplasts that support the endosymbiotic hypothesis of eukaryotic evolution. 4. Critical Thinking How would endosymbiosis have been mutually beneficial for pre-eukaryotic cells and for the small prokaryotes that invaded them? STRUCTURES AND FUNCTIONS Arrange the organisms listed below in the order in which they are thought to have originated on Earth by writing their names in the spaces provided in the figure. photosynthetic prokaryotes photosynthetic eukaryotes chemosynthetic prokaryotes aerobic eukaryotes heterotrophic prokaryotes Billion years ago 2.0 2.5 3.0 3.5 a b c d 4.0 e 76 Section 14-3 Review