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22 Cards in this Set

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According to the principle of biogenesis,
A. all living things come from other living things.
B. all living things come from nonliving things.
C. living things can come from either living or nonliving things.
D. living things can spontaneously generate.
A. all living things come from other living things. -For hundreds of years, people thought living things came from nonliving things. Careful studies since that time have revealed the fact that living things come from other living things.
All of the following examples once reinforced a popular belief in spontaneous generation except
A. fish showing up in a pond that was dry last season.
B. maggots failing to appear on rotten meat in a closed container.
C. sweaty clothing and husks of wheat placed in a jar as a recipe for the creation of mice.
D. the appearance of microorganisms in a lab sample that did not contain any microorganisms the previous day.
B. maggots failing to appear on rotten meat in a closed container. -Maggots failing to appear on rotting meat would likely indicate that new life did not generate spontaneously but rather came from contact from other organisms.
Which of the following was not part of the experiment conducted by Francesco Redi?
A. Redi observed that maggots seemed to emerge where flies had landed previously.
B. Redi observed that maggots turned into casings that eventually turned into flies.
C. Redi observed that jars containing meat required air to spawn maggots.
D. Redi concluded that maggots will form only where flies have laid eggs.
C. Redi observed that jars containing meat required air to spawn maggots. -Redi did not limit air from his experimental group. He limited the ability of flies to land on the meat by covering jars in the experimental group with netting.
Which of the following best describes the results of Lazzaro Spallanzi's experiments?
A. Heated air destroys a "vital force" needed for life to arise.
B. Microorganisms that contaminate food come from the air.
C. Spontaneous generation is indeed occurring.
D. Maggots come from microscopic eggs laid by parent flies.
B. Microorganisms that contaminate food come from the air. -Spallanzi boiled broth to test his hypothesis. When air was prevented from entering the flasks, microorganisms did not appear. When air was not restricted, microorganisms did appear.
Which of the following is not one of the steps that Spallanzi used in his experiment?
A. boiling meat broth in open flasks
B. bending the flask of the bottle so microorganisms would settle in the neck
C. sealing the flask of one bottle immediately after boiling and leaving the other bottle unsealed
D. evaluating the cloudiness of both broths
B. bending the flask of the bottle so microorganisms would settle in the neck -A century later, controversy surrounding Spallanzi's experiment was resolved when Louis Pasteur bent the neck of a flask and conducted an experiment similar to Spallanzi's.
How did Louis Pasteur use the curved neck of a flask to resolve the spontaneous generation controversy once and for all?
A. The curved neck prevented microorganisms from entering the broth.
B. The curved neck allowed Pasteur to observe the broth without boiling it. As a result, he did not destroy the alleged "vital force" that permitted life to arise spontaneously.
C. The curved neck allowed Pasteur to boil the broth for an entire year, making ongoing observations that provided the evidence to support the principle of biogenesis.
D. The curved neck allowed the "vital force" to enter the broth but did not permit microorganisms to enter.
B. Louis Pasteur accidentally solved the controversy related to spontaneous generation while doing other research for the Paris Academy of Science. -Pasteur intentionally experimented to resolve the controversy surrounding spontaneous generation. His efforts won him first prize in a contest sponsored by the Paris Academy of Science.
Computer models suggest that the first ingredients of our solar system formed from
A. repeated collisions of debris in space.
B. a swirling mass of gas and dust.
C. a swirling mass of gas and dust that collapsed inward.
D. a cloud of gas, dust, and debris that circled the sun.
B. a swirling mass of gas and dust. -The solar system began to form about 5 billion years ago when a swirling mixture of gas and dust formed a huge, interstellar cloud called a nebula.
The mass number of a certain isotope of oxygen is 17. The atomic number of oxygen is 8. An atom of this isotope of oxygen has
A. 9 protons and 8 neutrons.
B. 8 protons and 8 neutrons.
C. 8 protons and 9 neutrons.
D. 17 protons and 8 neutrons.
C. 8 protons and 9 neutrons -An atomic number of 8 means the atom has 8 protons and 8 electrons. A mass number of 17 means the atom has 9 neutrons and 8 protons. Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons.
All ____________ undergo radioactive decay.
A. atoms
B. elements
C. stable isotopes
D. unstable isotopes
D. unstable isotopes -Unstable, or radioactive, isotopes are elements that break up and give off energy in the form of radiation. The time it takes for one-half of a sample of an isotope to decay is called its half-life.
Before scientists conduct radioactive dating, they must know
A. how many half-lives have passed since a radioactive isotope formed.
B. where a rock sample was found.
C. the half-life of the radioactive isotopes they are studying.
D. whether life existed when the rock formed
C. the half-life of the radioactive isotopes they are studying. -In radioactive dating, scientists look at the amount of material a radioactive isotope contains, the length of time that material takes to decay, and the amount of stable isotopes present.
Carbon-14 has a half-life of 5,730 years. A sample containing carbon-14 is 17,190 years old. Therefore, the sample has gone through
A. one half-life.
B. two half-lives.
C. three half-lives.
D. four half-lives.
C. three half-lives. -The sample has gone through three half-lives, because 3 × 5,730 years = 17,190 years old.
Which of the following statements is true?
A. Carbon-14 can be used to date any organic object on Earth.
B. Carbon-14 can be used to date any organic object on Earth that contains carbon.
C. Uranium-238 can be used to date any organic object on Earth.
D. Uranium-238 can be used to date any organic object on Earth that contains uranium
D. Uranium-238 can be used to date any organic object on Earth that contains uranium. -The half-life of uranium-238 is approximately equal to the age of Earth, so any object containing uranium can be dated using uranium-238 dating.
Soviet scientist Alexander I. Oparin proposed that the first organic compounds came from
A. space dust.
B. the early atmosphere.
C. the Earth's early oceans.
D. gases from the Earth's interior.
B. the early atmosphere -Oparin theorized that Earth's early atmosphere was very different than it is today. The simplest organic compounds began in the atmosphere and then collected in water as the Earth's oceans formed.
Stanley Miller and Harold Urey helped support Oparin's theory by
A. performing an experiment that modeled the early Earth's atmosphere.
B. building on Oparin's theory with observations from a newly fallen meteorite.
C. verifying Oparin's assumptions about the chemical composition of the early atmosphere.
D. explaining where energy needed for the first chemical reactions to occur could have come from.
A. performing an experiment that modeled the early Earth's atmosphere. -Oparin had not tested his theory experimentally. Miller and Urey were able to demonstrate that Oparin's vision of the early atmosphere could produce a variety of organic compounds.
The cell-like structures scientists have been able to produce in a laboratory are important because they
A. simulate the first self-replicating information storage molecules.
B. show that all living things come from other living things.
C. show that hereditary material must exist in a cell before it can organize into a living cell.
D. show that aspects of cellular life can arise without direction from hereditary material.
D. show that aspects of cellular life can arise without direction from hereditary material. -Experiments in the laboratory and observations of the properties of coacervates and microspheres show that important aspects of cellular life can arise without direction from genes.
Until recently, scientists have believed that the sequence of hereditary information is ____________ as a template for ____________, which is a template for specific ____________.
A. RNA, DNA, proteins
B. DNA, RNA, proteins
C. proteins, RNA, DNA
D. proteins, DNA, RNA
B. DNA, RNA, proteins -The hereditary information in a DNA molecule is transcribed and delivered by mRNA from the nucleus to the cytosol, where it is transcribed to form specified proteins.
All of the following describe why RNA is a good suspect for triggering early cellular organization except
A. ribozymes can create other ribozymes.
B. RNA could have existed within cell-like structures.
C. certain RNA molecules can act like enzymes.
D. RNA would have been able to respond to natural selection.
A. ribozymes can create other ribozymes -Scientists have not been able to induce ribozymes (RNA molecules that act as enzymes) to form other ribozymes.
Which of the following is not an inference that scientists make about the first forms of cellular life on Earth?
A. The first cells must have been anaerobic.
B. The first cells were probably heterotropic prokaryotes.
C. The first autotrophic cells probably used photosynthesis to make food.
D. Strong environmental pressure promoted the evolution of autotrophs.
C. The first autotrophic cells probably used photosynthesis to make food. -The first autotrophic cells probably used chemosynthesis to make food, much like some archaebacteria that survive in the harshest conditions of today's Earth do.
Which of the following statements describes photosynthesis?
A. This type of autotrophy was relied upon most heavily by the first autotrophs.
B. This type of autotrophy requires obtaining energy from the oxidation of sulfur or other organic substances.
C. The earliest evidence of this type of autotrophy occurred around 4.5 billion years ago.
D. Cyanobacteria are modern-day relatives of the earliest practitioners of this type of autotrophy.
D. Cyanobacteria are modern-day relatives of the earliest practitioners of this type of autotrophy. -Cyanobacteria are modern-day practitioners of photosynthesis. Archaebacteria are modern-day practitioners of chemosynthesis.
Aerobic respiration
A. was damaging to early organisms.
B. is the byproduct of photosynthesis.
C. may have prevented oxygen from doing damage to early organisms.
D. is not related to photosynthesis in any way.
C. may have prevented oxygen from doing damage to early organisms. -Oxygen was damaging to many early unicellular organisms. An important early function of aerobic respiration may have been to prevent oxygen from destroying essential organic compounds.
Eukaryotic cells might have developed when
A. anaerobic prokaryotic cells invaded aerobic prokaryotic cells.
B. aerobic prokaryotic cells invaded anaerobic prokaryotic cells.
C. small prokaryotic cells grew larger and began photosynthesizing.
D. large prokaryotic cells grew even larger and began photosynthesizing.
B. aerobic prokaryotic cells invaded anaerobic prokaryotic cells. -Evidence suggests that small, aerobic prokaryotes entered and began to live and reproduce inside larger, anaerobic prokaryotes. The partnership that resulted is called endosymbiosis.
Which of the following statements related to endosymbiosis is false?
A. Chloroplasts and mitochondria are thought to have evolved through the process of endosymbiosis.
B. A prokaryote invading a large host cell may have performed the first cellular respiration.
C. Chloroplasts and mitochondria have genes that are the same as those found in the nucleus of the cell in which they exist.
D. Mitochondria and chloroplasts do not replicate according to the same cycle as the cell that contains them.
C. Chloroplasts and mitochondria have genes that are the same as those found in the nucleus of the cell in which they exist. -Mitochondria and chloroplasts have some genes that are different from those found in the nucleus of the cell that contains them.