chapter 15
The appearance of archosaurs in the Triassic period of the Mesozoic era began what is known as the ______, which lasted from the Triassic period to the Cretaceous period.
Age of Reptiles
Due to the significant and widespread effects of humans on the land, biodiversity, and climate, scientists propose that a new geological epoch has begun, called the
Anthropocene
Four to five species of the hominin genus ______ existed from about 4 to 2.5 million years ago.
Australopithecus
The Burgess Shale deposit shows a tremendous diversity of fossils from the ______ period of the Paleozoic era.
Cambrian
What term is used to describe a period of intensive animal diversification on Earth 543 million to 490 million years ago?
Cambrian explosion
Many species of worms, armored animals, shelled organisms, and trilobites arose in seas containing algae during the
Cambrian period of the Paleozoic era.
The ______ period of the Paleozoic era is also called the "Age of Amphibians."
Carboniferous
The ______ era is sometimes called the Age of Mammals, due to the adaptive radiation of mammals that occurred during the ______ period.
Cenozoic; Paleogene
The importance of the Miller experiment was that it was the first prebiotic simulation experiment to re-create chemical conditions that might have been present on early before life arose.
Earth
What is true about Ediacaran organisms?
They lived during the end of the Precambrian.
What marks the end of the Ordovician period?
a mass extinction
Select all of the following that are true about all species of the genus Homo.
considered human associated with stone tools larger brains than australopiths
DNA analyses indicating a close relationship between mitochondria and proteobacteria and between chloroplasts and cyanobacteria support the
endosymbiosis theory.
What evolved about 1.9 to 1.4 billion years ago?
eukaryotic cells
As depicted in the image, what step in the origin of life on Earth likely occurred immediately after the formation of monomers such as amino acids, nucleotides, monosaccharides?
formation of polymers
Select all the effects of the replacement of a hunter-gatherer lifestyle in Homo sapiens with the ability to increase food availability with agriculture.
formation of specialized occupations improved communication increased ability to explore new lands improved transportation
Climatic changes in East Africa, the Middle East, India, and much of Europe that began about 12 million years ago may have contributed to the evolution of
hominins.
Gibbons, orangutans, gorillas, chimpanzees, and humans all belong to the lineage of primates called the
hominoids.
Monkeys that live in Africa and Asia are called World monkeys, and monkeys that live in South and Central America are called World monkeys.
old new
The endosymbiont theory proposes that
the mitochondrion and chloroplast organelles of eukaryotic cells originated as free-living bacteria.
The ______ era lasted from 543 to 248 million years ago and is divided into six periods: the Cambrian, the Ordovician, the Silurian, the Devonian, the Carboniferous, and the Permian.
Paleozoic
What fossil is the oldest representative of the hominin lineage to date?
Ardipithecus ramidus
The first flowering plants appeared on land during the
Jurassic period of the Mesozoic era.
In his 1938 book titled The Origin of Life, ______ hypothesized that the absence of atmospheric ______ could have allowed nucleotides and amino acids to form.
Oparin; oxygen
Select all the correct statements regarding the lesser and great apes.
Orangutans, gorillas, chimpanzees, and humans are considered great apes. Gibbons are considered lesser apes.
Fossilized spores indicate that primitive plants ventured from the water to land during the ______ period of the Paleozoic era.
Ordovician
What organisms existed during the Ordovician period?
algae, corals, clams, ostracoderms, primitive land plants
What organisms existed in the Cambrian period?
algae, sponges, jellyfishes, worms, nautiloids, and trilobites
The first multicellular organisms to evolve were likely
algae.
Select all the characteristics of recent Homo.
arose from early Homo around 500,000 years ago lighter brow ridges associated with culture and tools
Select the three main groups that belong to the primate lineage.
monkeys prosimians hominoids
Select all the types of organisms that arose during the Silurian period of the Paleozoic era.
terrestrial animals vascular plants jawed fish fungi
What geologic time period is known as the "Age of Reptiles"?
Mesozoic erav
Gymnosperm plants became very prominent during the ______ period of the Paleozoic era.
Permian
Fossils of Australopithecus indicate that these hominins moved by
bipedal locomotion.
What skeletal adaptation might be present in a primate that moves by brachiation?
shoulder joint that allows 360-degree movement
Rank the following steps leading to the origin of a cell in the order they may have occurred, beginning with the earliest step at the top. Instructions
-simple precursor chemicals are present-small organic molecules form, such as amino acids, lipids, and nucleotides-polymers such as RNA and polypeptides form-genetic material encodes proteins, and lipid spheres form-formation of protocell, self-replicating system enclosed in a membrane
The Precambrian supereon spans what time period, approximately?
0.5 to 4 BYA
Eukaryotic cells arose about
1.5 bilion
Rank the order of time periods in the geological timescale from the longest at the top to the shortest at the bottom. Instructions
1.eons 2.eras 3.periods 4.epochs
By about ______ years ago, Homo sapiens began to shift out of the hunter-gatherer lifestyle with the development of ______ to obtain food, which allowed specialized occupations to arise in human societies.
10,000; agriculture
Early signs of culture in Homo sapiens is demonstrated in cave art that dates to about ______ years ago.
14,000
Prokaryotic cells were the first life forms on Earth and arose approximately
3.5 billion years ago.
The oldest known fossils are ______ years old and resemble formations made by ______.
3.7 billion; cyanobacteria
While geologic processes have destroyed most of Earth's initial crust, rocks that are about ______ years old have been found in Greenland.
3.85 billion
The first reptiles evolved about ______ million years ago during the Carboniferous period of the Paleozoic era.
300
The oldest hominin, Ardipithecus ramidus, dates back to
4.4 million years ago.
The species Homo sapiens had migrated out of Africa and colonized Europe, Asia, and Australia by about ______ years ago.
40,000
Fishes with jaws and freshwater fish arose during the Silurian period about
443 to 417 million years ago.
Humans and chimpanzees share a common ancestor that lived about ______ million years ago.
6
Primate ancestors that gave rise to the first ancient humans arose during the Neogene period about
6 million years ago.
The reign of giant reptiles on Earth ended about ______ million years ago due to a mass extinction that occurred at the end of the Meoszoic era.
65
The DNA nucleotide sequence of chimpanzees and humans are at least ______ identical.
96
While skin tone and some physical features differ in human populations due to microevolutionary forces, all living humans are
99.9% genetically similar.
The Carboniferous period of the Paleozoic era lasted over 50 million years and has been referred to as the "Age of ______."
Amphibians
Rank the hominin groups in the order they evolved, beginning with the earliest group at the top. Instructions
Ardipithecus 2. Australopithecus 3. Paranthropus 4. Homo
Select the four groups into which fossil hominins have been categorized.
Australopithecus Ardipithecus Homo Paranthropus
A mudslide during the Cambrian period preserved many organisms in a formation called the ______ that contains abundant and diverse fossils of Cambrian animals.
Burgess Shale
Underground coal beds contain the remains of ______ plants, such as forests of ferns and early seed plants.
Carboniferous
Select time periods from the Paleozoic era.
Carboniferous Cambrian Devonian Permian
Select the three reasons that clay could have been important in the polymerization of organic molecules on early Earth.
Clays consists of sheetlike minerals, forming flat surfaces. Some minerals in the clays could have acted as catalysts. Some clays contain minerals that release electrons, providing energy.
During what period of the Mesozoic era was Triceratops very abundant and widespread?
Cretaceous period
Fossils indicate that seed plants, ferns, and horsetails evolved during the ______ period of the Paleozoic era.
Devonian
The "Age of Fishes" refers to which of the following geologic time periods?
Devonian
The first amphibians appeared toward the end of the ______ period of the Paleozoic era.
Devonian
Select all of the following statements about early Earth that are correct. Refer to the figure.
Earth's crust formed approximately 4.2 billion years ago. The first animals arose in the ocean about 570 million years ago. Eukaryotes arose about 1.5 billion years ago.
What Precambrian organisms had a variety of forms, became extinct around 544 million years ago, and left no known descendants?
Ediacarians
During the ______, early Earth was subjected to ultraviolet radiation, volcanic eruptions, earthquakes, and bombardment by meteorites.
Hadeon eon
Fossils of the genus ______ are associated with stone tools and have larger brains and bodies than australopiths.
Homo
Select all the species that are considered "early Homo."
Homo habilis Homo ergaster Homo erectus
Of the following species of the genus Homo, which one is still alive?
Homo sapiens
Select all the species that are considered "recent Homo."
Homo sapiens Homo heidelbergensis Homo neanderthalensis Homo floresciensis
Select all the ways in which humans could be considered the dominant species on Earth.
Humans have colonized most continents. Humans have changed other species to fit their needs. Humans have altered the Earth's surface.
Select all the hypotheses that describe how single-celled life forms may have developed into multicellular life forms.
Individual cells united, and groups of cells took on specialized life tasks, forming a multicellular organism. An individual cell divided and the two cells remained together; this process repeated, resulting in a multicellular organism with specialized cells.
The first mammals were small and arose during the
Jurassic period.
What is true about the DNA found in the eukaryotic organelles that were derived from the endosymbiosis of proteobacteria and cyanobacteria?
Many genes have moved to the nuclei of the host cells.
The figure represents the apparatus used by
Miller to duplicate the conditions on early Earth and determine if organic molecules could arise.
The continents approached their current positions during the
Neogene period.
Select all of the following that describe the conditions on early Earth.
Numerous volcanic eruptions and earthquakes were occurring. Atmospheric pressure was at least 10 times the pressure of present Earth. Surface temperatures ranged from 500oC to 1000oC. It cooled enough to form a crust about 4.2 billion years ago.
What is the difference between Old World monkeys and New World monkeys?
Old World monkeys are native to Africa and Asia, and New World monkeys are from South and Central America.
Select all the important events that occurred during the Precambrian supereon.
Oxygen accumulated in the Earth's atmosphere. Photosynthesis evolved. Multicellularity arose. Life originated.
What hominin existed 3 to 1.5 million years ago, had large teeth and protruding jaws, and did not give rise any other hominin genus?
Paranthropus
Reptiles that laid amniotic eggs arose during the ______ period.
Permian
The cotylosaurs were reptiles of the early ______ period that eventually gave rise to pelycosaurs (sailed lizards), dinosaurs, and all other reptiles.
Permian
Select all the ways that the evolution of photosynthetic organisms affected subsequent changes on Earth.
Photosynthetic organisms became energy sources for other eukaryotic organisms. Ozone formed, which blocked ultraviolet radiation Aerobic organisms began to evolve.
The appearance and extinction of several species of human (genus Homo) occurred during the ______, but only one species survived to the present.
Pleistocene epoch of the Quaternary period
Several ice ages in which huge glaciers covered 30% of Earth's surface and then withdrew occurred during the
Pleistocene epoch of the Quaternary period.
The ______ epoch comprises nearly all of the ______ period in the Cenozoic era.
Pleistocene; Quaternary
An extinct group of organisms that existed during the ______ were the Ediacarans, and the Ediacarian period is named in their honor.
Precambrian
The geologic time period that covers 2.58 million years ago to present is called the ______ period.
Quaternary
In some prebiotic simulation experiments, ______ molecules were formed on clay surfaces with positive charges.
RNA
Select all the reasons why RNA may have been the first informational molecule.
RNA can catalyze chemical reactions. RNA can duplicate itself. RNA can use stored information to produce proteins. RNA stores genetic information.
What idea proposes that RNA could have been the first self-replicating precursor to life on Earth?
RNA world
Select all of the following that are true about the evolution of the genus Homo.
Several species of hominin lived in Africa at the same time. Homo sapiens is the only remaining species. Scientists speculate that H. sapiens may have interbred with H. neanderthalensis.
The first plants to have vascular tissues evolved during the ______ period of the Paleozoic era.
Silurian
What correctly describes the size of ancient amphibians?
Some were up to 9 meters long.
In his book titled ______, Oparin suggested that ______ could have formed in a reducing atmosphere.
The Origin of Life; amino acids and nucleotides
Select all the correct statements regarding the Quaternary period.
The Quaternary period is the present geologic time period. Ice sheets and glaciers formed and receded during parts of the Quaternary period. The Quaternary period is part of the Cenozoic era.
Select all the correct statements regarding the asteroid and the resulting mass extinctions that ended the Mesozoic era.
The asteroid was about 10 kilometers in diameter. So much debris was cast into the atmosphere that photosynthesis was essentially nonexistent for about 3 years. The point of impact of the asteroid was near the Yucatán peninsula.
A bubble composed of a phospholipid membrane is called a
The bacteria and archaea split apart from a common ancestor between 3 BYA and 2.5 BYA. Archaea and bacteria, even though simpler than eukaryotes, still flourish today.
Select all of the evidence suggesting that the chloroplasts of some photosynthetic organisms arose by the endosymbiosis of a eukaryotic photosynthetic cell (secondary endosymbiosis).
The chloroplasts have three or four membranes. The chloroplasts retain remnants of a nucleus.
Select geological, biological, and climate changes that occurred during the Paloegene period of the Cenozoic era and that affected speciation and extinctions of organisms during this time period.
The oldest known bat fossil dates to the Paleogene period. Wet, warm forests were widespread. Tectonic plates shifted and created mountains.
Select all the evidence used to support the endosymbiont theory proposed in the 1960s.
There are similarities in photosynthetic pigments in chloroplasts and cyanobacteria. There are similarities in the size, shape, and membrane structure of chloroplasts, mitochondria, and bacterial cells. Chloroplasts and mitochondria contain DNA, RNA, and ribosomes, which are similar to those in bacterial cells. Mitochondria and chloroplasts divide in a way that is similar to bacterial division.
Select all of the following that are true about the Cretaceous period of the Mesozoic era.
Tyrannosaurus existed in western North America. Flowering plants were extremely diverse. Marine reptiles were present in the seas. Birds and pterosaurs shared the skies. Dinosaurs moved in large herds.
The end of the Devonian period is marked by
a mass extinction of marine life.
What event correlates with the evolutionary explosion of life that began around 1.5 billion years ago?
accumulation of oxygen in atmosphere
After a week of running the experimental apparatus shown in the image, what did Miller find in the pinkish, condensed liquid at the bottom?
amino acids
The products of Miller and Urey's 1953 experiment contained
amino acids.
Select all of the following that were likely components of Earth's early atmosphere, as proposed by Oparin in his 1938 book.
ammonia (NH3) methane (CH4) water (H2O) hydrogen (H2)
Select all of the following that went extinct at the end of the Mesozoic era about 65 million years ago.
ammonites pterosaurs plesiosaurs nonavian dinosaurs
What key characteristic evolved in early reptiles that allowed embryonic development to occur completely on dry land?
amniotic egg
Toward the end of the Devonian period of the Paleozoic era, ______ first appeared.
amphibians
Select all the organisms that were abundant and flourishing during the Carboniferous period of the Paleozoic era.
amphibians bryozoans foraminiferans ferns insects
What organisms existed during the Carboniferous period?
amphibians, bony fishes, sharks, giant dragonflies, seed plants
All the major phyla of ______ appeared during the Cambrian explosion.
animals
Select all of the following changes that occurred about 12 million years ago that may have contributed to the evolution of hominins.
appearance of open plains new food resources on African savannas formation of the Himalayas
Reptiles called ______ arose during the Triassic period and were the ancestors of dinosaurs.
archosaurs
Many reptile groups that survived the Triassic period and continued to evolve in the Jurassic period
became larger and dominant.
Select all of the skeletal adaptations present in humans that allow locomotion by bipedalism.
big toe not opposable long, strong leg bones bowl-shaped pelvis
Select the feature that is unique to members of the genus Homo and absent in chimpanzees and gorillas.
bipedal locomotion
A primate fossil with a foramen magnum located beneath the skull, rather than at the rear of the skull, likely moved by ______, which is walking upright.
bipedalism
Being able to carry objects and use tools may have been advantages of ______ for early hominins living in the open plains.
bipedalism
Humans have a bowl-shaped pelvis, fixed big toes, and robust lumbar vertebrae, all skeleton adaptations for what type of locomotion?
bipedalism
Some hominoids, such as gibbons and orangutans, move among tree branches by ______, swinging from one arm to another as the body dangles beneath.
brachiation
The use of tools and language is related to the development of larger ______ in humans.
brains
Miller's experiment was criticized because he did not use the gas ______, even though it was abundant in the early Earth's atmosphere. When it is present, organic molecules still form.
carbon dioxide
Quartz crystals found in the 3.85-billion-year-old Isua rock formation in Greenland contain
carbon isotopes found in organisms.
After RNA arose and the synthesis of proteins and DNA began, protein molecules eventually took over many of RNA's ______ roles, and DNA molecules became stable molecules for ______.
catalytic; information storage
What key feature of complex organisms was made possible by the evolution of multicellular organisms?
cell specialization
Around 4 billion years ago, the first ______ formed.
cells
Through molecular techniques, scientists have discovered that the genes of humans and ______ are nearly identical.
chimpanzees
Select all of the following included in the lineage of primates known as hominoids.
chimpanzees orangutans humans gibbons gorillas
What evidence indicates that an asteroid colliding with Earth near the Yucatán peninsula caused a mass extinction at the end of the Cretaceous period?
clay-filled impact crater layer of iridium in Cretaceous rock huge semicircle of sinkholes
What may have provided a surface for the linking of organic monomers because it contains minerals that may have had a catalytic role?
clays
What repeatedly hit Earth's surface during its first 500 to 600 million years?
comets, asteroids, and meteorites
Select all the organisms that were present in the seas during the Ordovician period of the Paleozoic era.
corals sponges algae clams jawless fish
Knowledge, beliefs, and behavior are all part of ______, which is a by-product of the large human brain.
culture
Select all of the unique characteristics of the modern human species.
culture, knowledge, and beliefs can change faster than biological evolution activities can have effects on Earth's climate
The evolution of photosynthesis made which of the following possible? Select all that apply.
decrease in atmospheric CO2 concentration evolution of aerobic organisms accumulation of atmospheric oxygen formation of ozone
What may have caused the mass extinction at the end of the Ordovician period of the Paleozoic era?
decreasing temperatures as Gondwana drifted toward the South Pole
The size and shape of fossil teeth reveal information about a primate's
diet.
Multicellular animals, plants, and fungi arose from
different lineages of protists.
The capacity of nucleic acids to mutate in progenotes may have allowed the evolution of
different metabolic pathways.
Fossils of Homo that date back to 2 million years ago would be considered
early Homo.
In Miller's experimental design to test Oparin's prediction about Earth's early atmosphere, what did Miller pass the gases through to simulate lightning?
electrical discharges
According to the theory, free-living bacteria were engulfed by prokaryotic cells and eventually became chloroplasts and mitochondria.
endosymbiont
Although scientists do not know the exact origin of eukaryotic cells, the ______ theory does explain the origin of the mitochondria and chloroplasts.
endosymbiosis
Select all of the following that are true about Paranthropus.
evolved from Australopithecus existed more recently than Australopithecus
Rising and falling global temperatures, advancing and retreating glaciers, and changes in the gases in the atmosphere have led to numerous
extinction and speciation events.
Select all the new species of plants that evolved during the Devonian period of the Paleozoic era.
ferns horsetails seed plants
What very successful type of fishes first arose during the Devonian period?
fishes with bony skeletons
The family tree of hominins has been constructed mostly based on
fossil features.
Select all the types of fossils present in the Green River formation in Wyoming that dates back to the Eocene epoch of the Paleogene period, 50 million years ago.
freshwater fish crocodiles and snakes flowering plants and ferns bats insects and snails
Select all the Pleistocene mammals that went extinct.
giant sloths saber-toothed cats North American camels mastodons and mammoths
Match each term with the primates it describes. Instructions hominoids lesser apes hominids
gibbons, orangutans, gorillas, chimpanzees, humans gibbons orangutans, gorillas, chimpanzees, humans
Select all the characteristics shared by primates.
grasping hands with opposable thumbs large brains relative to body size eyes set in the front of the skull fingers and toes with flat nails
Select the types of habitats that opened up for mammals due to climate change and geologic events during the Paleogene period.
grasslands forests woodlands
During the Permian period, what type of plant became more prominent?
gymnosperms
A diversity of what type of mammals grazed the grasslands of North and South American during the start of the Paloeogene period?
hoofed
Although not the most numerous species, ______ can be considered the current dominant species on Earth due to colonization and alteration of Earth.
humans
The cladogram shows that
humans and gorillas share a more recent common ancestor than humans and orangutans do.
Select all the gases that Miller and Urey used in their 1953 experimental apparatus.
hydrogen methane water vapor ammonia
Photosynthesis likely arose first in aquatic bacteria that used ______ as an electron donor.
hydrogen sulfide
In places called ______, cold ocean water mixes with minerals from Earth's interior under high temperatures, and these may have been the sites of simple organic molecule synthesis on early Earth.
hydrothermal vents
In general, the size of reptiles ______ from the Triassic to the Jurassic period of the Mesozoic era.
increased
Select all the advantages that may have led to the evolution of bipedalism in early hominins living on African savannas.
increased ability to carry objects freed hands to use tools
Multicellularity arose
independently in multiple lineages.
Extensive deposits of ______ provide evidence that Earth's atmosphere began to contain oxygen released from photosynthesis beginning about 2 billion years ago.
iron
In deep-sea hydrothermal vents, what may have acted as a catalyst for the reactions that formed simple organic compounds?
iron
Dark skin pigmentation is more common near the equator because it
is more protective against UV radiation.
Some types of primates have skeletal adaptations for ______, which is running along the ground with the weight resting on the knuckles.
knuckle-walking
Select all the characteristics of the amphibians of the Carboniferous period.
laid eggs in water life cycle still tied to water
Select all the organic molecules that Miller and other researchers were able to create using different mixtures of chemicals in early Earth prebiotic simulation experiments.
lipids nucleotides amino acids carbohydrates ATP
Using the figure, select all the correct statements about the diversity of life.
liposome.
The earliest cells probably all
lived in the absence of oxygen.
What type of fishes evolved during the Devonian period and had fleshy, powerful fins that could be used as feet?
lobe-finned fishes
Select all of the skeletal adaptations in a primate fossil that might indicate locomotion by knuckle-walking.
longer arms than legs foramen magnum opening at the back of the skull
Select all of the following that are prosimians.
lorises lemurs tarsiers aye-ayes
Lobe-finned fishes and early amphibians could obtain oxygen from the environment from both gills and
lunglike structures.
The very large asteroid impact on Earth at the end of the Mesozoic era opened up many habitats previously occupied, and the ______ underwent an adaptive radiation during the Cenozoic era.
mammals
What occurred at the end of the Cretaceous period?
mass extinction of dinosaurs that opened up habitats
Select all of the following that occurred at the end of the Triassic period of the Mesozoic era.
mass extinction that affected many aquatic and land animals rise of the large dinosaurs
The term "RNA world" describes the possibility that self-replicating RNA
may have been present in multiple forms, forming a pre-life community of molecules.
Under the right temperature and pH, phospholipids may have formed from precursors and assembled into
membrane-like structures.
Some evidence indicates that clays may have played an important role in the formation of early macromolecules. What component of clay may have acted as a catalyst to speed chemical reactions?
minerals, such as iron pyrite
Chloroplasts and mitochondria both developed in eukaryotic cells through endosymbiosis, though were probably the first of the two organelles to develop because they are found in all eukaryotes.
mitochondria
The endosymbiont theory explains the origin of which two eukaryotic organelles?
mitochondrion chloroplast
The Permian period ended with a mass extinction event in which
more than 90% of marine species in shallow water areas died; on land many insects, amphibians, and reptiles also died.
What may have allowed different metabolic pathways to arise in progenotes?
mutation of nucleic acids
Select the major gases found in Earth's present-day atmosphere.
nitrogen carbon dioxide oxygen water vapor
Chromosomes of humans and chimpanzees are extremely similar; one main difference is that humans have ______ due to the fusion of two smaller chromosomes early in the lineage that led to humans.
one less chromosome pair
What did the earliest cells likely use as a source of carbon and energy?
organic molecules
Use the diagram to place the following events of early Earth in order, from the earliest event at the top to the most recent at the bottom. Instructions
origin of life -origin of photosynthesis -oxygen beginning to accumulate in the atmosphere -oldest eukaryotic fossil
According to Oparin's book The Origin of Life, the atmosphere of early Earth did not contain ______ gas.
oxygen
The atmosphere of Earth today primarily contains the following gases: carbon dioxide, water vapor, nitrogen, and .
oxygen
The right temperature, pH, and precursor molecules could have allowed ______ molecules to form membrane-like structures.
phospholipid
What pathway evolved that allowed some types of early cells to use carbon dioxide as a source of carbon and sunlight as a source of energy to synthesize their own food molecules?
photosynthesis
Liposomes are formed when
pieces of a phospholipid membrane assemble into a bubble.
While land animals were largely spared, many marine organisms, such as jawed fishes called ______, became extinct at the end of the Devonian period.
placoderms
During the Silurian period of the Paleozoic era, the first with vascular tissues evolved.
plants
The name Carboniferous means "coal bearing." During the Carboniferous period, ______ dominated the landscape in tremendous areas of swamps and forests and were preserved as coal over millions of years after they died.
plants
As the figure proposes, sunlight may have provided the energy and iron pyrite in clays could have acted as a catalyst for the
polymerization of nucleotides.
The arrangement of minerals in sheets within clays may have provided a surface in which chemical building blocks could have been linked to form
polymers.
Miller's experiment was the first ______, and it showed how ______ could form from the simple molecules that were likely present on early Earth.
prebiotic simulation; biological molecules
Progenote, protocell, and protobiont are terms that describe
precursors of cells.
Monkeys, apes, and humans all belong to a group of mammals called ______ and share a suite of physical characteristics.
primates
An ancient aggregate of RNA, DNA, proteins, and lipids is called a
progenote.
The first cells on the Earth were
prokaryotic.
About 4 billion years ago, clays may have been the sites of RNA synthesis because their surfaces
promote the formation of covalent bonds.
Lemurs, lorises, tarsiers, and bush babies are all examples of a group of primates called
prosimians
The primate lineage contains three groups: the ______ (lemurs, lorises, and tarsiers), the monkeys, and the ______ (apes, including humans).
prosimians; hominoids
In the "RNA world," RNA may have begun to encode ______ that act as enzymes, and when the enzyme reverse transcriptase arose, a more stable informational molecule called ______ could have been made from RNA.
proteins; DNA
In the evolution of eukaryotic cells, the endosymbiosis of a ______ is thought to have given rise to mitochondria, and later, the endosymbiosis of a ______ bacterium is thought to have given rise to chloroplasts.
proteobacterium; photosynthetic
During Earth's early history, chemical aggregations may have formed and been destroyed by _______, but by around 4 billion years ago, the first ______ were able to survive, reproduce, and diversify.
radiation and space debris; cells
The earliest multicellular fossil was a ______ that lived about 1 billion years ago.
red alga
Select all the proposed reasons for the mass extinction that occurred at the end of the Permian period.
release of toxic hydrogen sulfide by decomposing bacteria volcanic eruptions, causing climate change decreased sea levels increase in carbon dioxide in the atmosphere, thus decreasing available oxygen
Scientists propose that the Golgi apparatus, endoplasmic reticulum, and nuclear envelope may have arisen by
repeated infoldings of the outer cell membrane.
What vertebrate group was the most diverse during the Jurassic period of the Mesozoic era?
reptiles
During the Carboniferous period, some amphibians arose that could lay eggs with hard shells on land. These amphibians gave rise to the first
reptiles.
Select all the conditions present in deep-sea hydrothermal vents that may have favored prebiotic formation of molecules.
rich mineral content dissolved CO2 high pressures extremely hot water meeting cold ocean water
Some researchers suggest that ______ molecules were the first information molecules formed on early Earth.
rna
In photosynthetic protists whose chloroplasts have three or four membranes, the chloroplasts are thought to have arisen by
secondary endosymbiosis
Select all of the global environmental changes that have affected speciation and extinction on Earth.
shifting continents over the Earth's surface advancing and retreating glaciers changing temperatures increased atmospheric oxygen
shoulder joint that allows 360-degree movement
shoulder joint that allows 360-degree movement
Select all of the following that are important features of primate skulls that a paleontologist might study.
size of the jaw bones prominence of the ridge of bone above the eyes shape of the tooth row presence of a sagittal crest
Scientists examining evolutionary relationships of prehistoric humans have most often used comparisons of
skeletal features of fossils.
The oldest known fossils are about 3.7 billion-year-old and resemble formations called ______ made by prokaryotes called ______.
stromatolites; cyanobacteria
What was likely released into the environment by Earth's first photosynthetic organisms, which used H2S as an electron donor?
sulfur
The Miller experiment, also called the first prebiotic simulation, was an attempt to
test whether organic molecules could form from the chemical conditions on early Earth.
What region was last to be colonized by Homo sapiens about 20,000 years ago?
the Americas
Select all of the vertebrates that were present in the Jurassic period of the Mesozoic era.
the first birds the first small mammals marine reptiles pterosaurs, apatosaurs, and stegosaurs sharks and rays giant reptiles
Scientists can determine the type of locomotion used by animals through examination of the foramen magnum,
the hole in the skull where the spinal cord leaves the brain.
The image shows how membrane infolding may have given rise to
the nuclear envelope and endoplasmic reticulum.
Eons, eras, and periods are terms used to define major geological or biological events within Earth's geological .
timesclae
Select all of the following that large teeth with many ridges indicate in a primate fossil.
tough diet grinding function
True or false: Cells do not assemble mitochondria and chloroplasts, which instead divide like bacterial cells.
true
True or false: Earth's surface was frequently exposed to ultraviolet radiation and meteorites during its first 500 to 600 million years.
true
What could a scientist know about a primate's life if its fossil skull had a prominent sagittal crest?
type of diet and strength of the jaws
Select all of the characteristics that may relate to the evolution of a large brain in humans.
use of language living in social groups tool use
The first fossils of ______ are known from the Ordovician period of the Paleozoic era.
vertebrates
The first ______, which were jawless fishes called ostracoderms, arose during the ______ period of the Paleozoic era.
vertebrates; Ordovician
When photosynthetic bacteria began to use ______ as an electron donor in photosynthesis, ______ began to be released and to accumulate in Earth's atmosphere, as evidenced by iron-rich sediments in oceans.
water; oxygen
During the Carboniferous period of the Paleozoic era, the bony fish and sharks that arose during the Devonian
were beginning to resemble modern forms.
The first organisms on Earth
were simpler than any cell known today.
