Biology Principles of evolution
How can morphological traits be used to explain evolution?
The more traits animals share, the more closely they are related.
What will be the frequency of the dominant allele in a population of 100 tigers if there are 90 dominant alleles?
0.45
If a population is in Hardy-Weinberg equilibrium and the A allele has a frequency of 0.7, what will be the frequency of homozygous dominant individuals?
0.49
If you have a population of 30 frogs and they have 40 A alleles for a gene, what is the frequency of the A allele?
0.67
Animals can be divided into groups that have different numbers of tissue during embryonic development. Most animals have how many layers?
3
How many total, non-unique alleles are there for each gene in a population of 400 humans?
800
natural selection
A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
How does speciation occur via natural selection?
A species is split into multiple groups that are shaped by different environments.
Homo sapiens
A species of the creatures Hominid who have larger brains and to which humans belong, dependent of language and usage of tools.
The oldest fossils of hominids and Homo sapiens were found in what continent?
Africa
What is one of the four main points of Darwin's theory of evolution by natural selection?
Animals compete.
deuterostomes
Animals in which the mouth forms 2nd during development and the opening becomes the anus.
How are the number of embryonic tissue layers used to divide animals into groups?
Animals that have tissues are divided into two groups: those that have two tissue layers and those that have three.
Which statement correctly compares radial and bilateral symmetry?
Animals with radial symmetry have symmetry around a central axis, while animals with bilateral symmetry can be divided into half equally.
During which era did mammals diversify and occupy almost every available niche?
Cenozoic
Which time period is called the "Age of Mammals?"
Cenozoic Era
Evolution
Change over time
biosphere
Earth's life zone, a closed system that regulates itself, Scientists hypothesize the biosphere evolved at least 3.5 billion years ago
The best index fossils are of organisms that were long-lived.
False
Trilobites are useful index fossils because they lived in the sea.
False
Which 16th century scientist's work led to the concepts of extinction and the age of Earth?
Georges Cuvier
Which scientist's ideas eventually lead to the theory that Earth is several billion years old?
Georges Cuvier
Which species was the first to exhibit body proportions similar to ours?
Homo erectus
Which species of hominid means "handy man" referring to its use of stone tools?
Homo habilis
What is the difference between protostomes and deuterostomes?
In deuterostomes, the mouth forms second during development.
Which of the following statements is true about the theory of plate tectonics?
It explains how the continents moved and fossil findings are evidence that they were once a supercontinent.
What was the dominant life form during the Mesozoic era?
It was called the "age of reptiles" mainly due to the presence of dinosaurs.
What makes one animal less adapted than another?
Its phenotype is less suited to its environment.
Why do you think our ancestors began to migrate out of Africa?
Many scientists believe that climate change led to food and water shortages. They went in search of "greener pastures."
Which era began and ended with mass extinctions?
Mesozoic
Which hominid species is our closest extinct relative?
Neanderthal
In general, how would you compare Neanderthals to Cro-Magnons?
Neanderthals were stronger and stockier than Cro-Magnons with slightly smaller brains and a prominent brow ridge. They both used tools, language, fires, and buried their dead. Cro-Magnons were more sophisticated and are the same as modern humans.
molecular evidence
Our genetics provide evidence of how closely we are related to one another and to all other species. evidence in DNA that shows evolution has occurred. Like the similarity in DNA between Chimpanzees and humans.
Which era of the Phanerozoic Eon included the most rapid and widespread diversification of life in Earth's history?
Paleozoic Era
In what era do trilobite fossils belong?
Proterozoic
If you have the frequency of the dominant allele for a gene, how do you get the frequency of the recessive allele?
Subtract the frequency of the dominant allele from 1.
Cro-Magnon
The 1st Homo sapiens. More modern sophisticated humans. Had complex social organizations, modern language capabilities, and lived by hunting. These humans spread across Siberia to North America. By about 12,500 years ago, humans had reached all the way down to South America.
Morphology
The branch of science that deals with studying structures and features of organisms
What was the early Palezoic era most known for?
There was rapid diversification of life forms during this era. This is true until the mass extinction that ended the era.
Why did the Neanderthals evolve to have shorter and stockier bodies than other humans did?
They lived in Europe which had a colder climate.
Homo erectus
This early human lived between 1.89 million and 143,000 years ago. possessed modern human-like body proportions with relatively elongated legs and shorter arms compared to the size of the torso. These features are considered adaptations to a life lived on the ground and the ability to run long distances. This species was the first to migrate out of Africa into Europe and Asia.
Neanderthals
This early human. He lived in Europe 200,000 to 40,000 years ago. Our closest extinct human relative. They were stockier and shorter than us, but their brains were almost as large. They made and used sophisticated tools, used fire, lived in shelters, and buried the dead.
Homo habilis
This species, one of the earliest members of the genus Homo, lived 2.4-1.4 million years ago. It has a slightly larger brain case and smaller face and teeth than in Australopithecus or older hominid species. But it still retains some ape-like features, including long arms and a moderately protruding face. The name means "handy man," referring to its use of stone tools.
Hardy-Weinberg equilibrium
When a population is not evolving and its allele proportions are staying the same from generation to generation
What is relative dating?
a method of dating geological layers based on layer depth
stratigraphy
a method of studying geological (rock) layers.
geologic time scale
a way of dividing Earth's long history into distinct chunks of time and representing them graphically.
When did Homo sapiens first appear?
about 34,000 years ago
protostomes
animal in which the mouth forms 1st during development.
Which animals are most closely related?
animals that are closest together on a phylogenetic tree
symmetry
as called "body plan" means that an animal has the same body parts around a specific axis. (morphological trait)
Neanderthals had a wide, stocky body. Why did they evolve to have this characteristic?
because they migrated to Europe with a colder climate
Why are bacteria necessary to life?
because they move and make biologically important elements available to the organisms that need them.
What does natural selection favor?
beneficial traits
coelom
body cavity, the coelom protects the important inner organs and holds them in place, while allowing some movement.
What are stromatolites?
colony of cyanobacteria, contributed to oxygenating the atmosphere.
Which of the following was the key point of Darwin and Wallace's theory of evolution by natural selection?
differential reproduction
Which of the following factors will not disrupt the Hardy-Weinberg equilibrium?
dominant alleles
tissue layers
ectoderm, mesoderm, endoderm, Endo- means "inner," ecto- means "outer," and meso- means "middle(Morphological trait)
What did Miller and Urey include in their experiment to simulate the effects of lightning?
electric charges
What word means how organisms change over time?
evolution
Darwin's theory of evolution
evolution occurs by natural selection. Has 4 parts, overproduction, variation, competition, differential reproduction
Early hominid fossils exhibited a physical characteristic that made them different from apes. What did they have?
exhibited bipedalism
Because brachiopods changed through time, they are not good index fossils.
false
Clues about early human behavior can be determined by looking at what piece of evidence?
footprints
Hominids
humans and their direct ancestors. ancestors include human like beings that belong to a genus other than homo, such as Australopithecus.
Which BEST identifies specific geologic eras throughout Earth's history?
index fossils
Our atmosphere is a mixture of gases that surrounds Earth. What are the two primary gases of our atmosphere?
is composed of approximately 78% nitrogen and 21% oxygen. The remaining 1% is a combination of other gases.
As early humans faced environmental changes and evolved larger bodies, what other human characteristic evolved?
larger, more complex brains
Which major event occurred during the Paleozoic era?
life began transitioning from ocean to land
What was simulated in the Miller-Urey experiment?
lightning bolts
Australopithecus
lived from 4.2-2 million years ago. Members had both ape-like and human characteristics with smaller brains and projecting lower jaws. They lived in Africa.
Cephalization
means that an animal has much of its nervous system centered in one end, which is usually called "the head."
molecular clocks
models that use mutation rates to measure evolutionary time
Primates
monkeys, apes, and humans. Have hands that contain 5 digits and can grasp things. They have flexible feet for walking or climbing.
Segmentation is an example of which of these?
morphological trait
Symmetry and cephalization are an example of which of these?
morphological trait
What are the three possible types of body cavity an animal may have?
no coelom, pseudocoelom, coelom
What kind of research did Darwin do that led to his theory of evolution?
observations of plants and animals in many places
Segmentation
occurs when parts of an animal are in repeated segments (pieces.) important because it allows animals to have special parts that do special things.
What is one of the four sections of Darwin's theory of evolution by natural selection?
overproduction
What was the MOST important gas contributed by stromatolites?
oxygen
What was the most important gas contributed by stromatolites?
oxygen
What is used by scientists to visualize how morphology explains evolution?
phylogenetic tree
morphological traits
physical characteristics used to compare and contrast living things.
What is the difference between continental drift and plate tectonics?
plate tectonics explains the process of the movement of the tectonic plates, while continental drift does not.
What evidence does banded iron in rocks provide?
presence of oxygen 2.7 billion years ago
Which scientific method provides the BEST evidence that life began 3.8 billion years ago?
radiometric dating
Which of the following are methods that result in sexual selection in animals? (Choose all that apply)
rutting, mate selection, mate competition
Morpholgical evidence
scientist have uncovered more than 6,000 hominid fossils. These fossils allow researchers to study changes that occurred in brain and body size, locomotion, diet and other aspects regarding they way of life of the early human species.
What BEST describes the first prokaryotes?
single-celled
Hardy-Weinberg Principle
states that in a particular population, the proportions of alleles for each gene do not change unless the population is evolving.
What structure exists as a fossilized mat of cyanobacteria today?
stromatolite
Which term describes how an animal's body can be equally divided around an axis?
symmetry
Bipedalism
the ability to walk upright on two legs
what do scientists compare at the molecular level to determine evolutionary relationships?
the base sequence in DNA and amino acid sequences in proteins are used for comparison.
What was one of Alfred Russel Wallace's major contributions to the study of evolution?
the mechanism of natural selection
human evolution
the study of how humans and their direct ancestors hanged over time into humans like us.
How do scientists use index fossils?
to identify specific geologic eras
How are animals divided into groups based on the morphological trait of the number of tissue layers during development?
two groups: those that have three tissue layers in their embryos and those that have two