Biology Module 6

sympatric speciation

evolution of a new species from a surviving ancestral species while both continue to inhabit the same geographic region.

Darwin called the ability of an organism to survive and reproduce

fitness

Which of the following is not required for a population to be in Hardy-Weinberg equilibrium?

gene flow

In the early part of the Mesozoic the ________ plants replaced the ________ plants as the dominant plant group on Earth

seed; non-seed

The operation of natural selection depends upon the fact that ____.

some individuals have a better chance to produce more offspring

In seed plants, the gametophyte plant remains enclosed within the

spore

The average human birth weight is about seven pounds. Babies which are too large or too small have a reduced rate of survival. What type of natural selection would explain favoring of the average-sized birth weight?

stabilizing selection

The oldest proposed cell microfossils come from structures called _____.

stromatolites

Individuals in a population that have a variation which gives them an advantage in their environment are more likely to

survive and reproduce

The process of a new species arising within the range of the parent species is called

sympatric speciation

The newest rank used by many biologist is

domain

The spark discharge in the accompanying figure represents ____.

electrical energy in the environment.

Evidence which supports the theory of evolution is found in the study of

embryos geology biogeography

The ____ hypothesis states that mitochondria and chloroplasts evolved from bacteria.

endosymbiont

The first cells were likely _____.

anaerobic prokaryotes

The above illustration, A are the wings of a butterfly, B are the wings of a bat. These wings are said to be

analogous structures

What is the strongest evidence for the idea that present-day eukaryotic aerobes are the descendants of the successful symbiotic association of anaerobes and aerobes?

A mitochondrion has its own set of DNA molecules.

Darwin's exposure to Lyell gave him insight on the ____.

enormous lengths of time required for geologic events

In the population genetics simulation, simulation 1 where no mutation occurred, after 200 generations, what was the final A1 allele frequency for a population of infinite size (modeled by black line)?

0.5

In the population genetics simulation, simulation 2 where A2 to A1 mutations occurred, after 200 generations, which value best approximates the final A1 allele frequency for a population of infinite size (modeled by black line)?

0.9

How many species of marsupials are native to the United States?

1

The fossil record indicates that flowering plants first appeared about _______ million years ago.

140 to 150

When was "Origin of Species" first published?

1859

About ____ years ago, oxygen released by cyanobacteria began to rise significantly in the Earth's atmosphere and waters.

2.5 billion

From the fossil record it appears that plants probably move onto land about _______ million years ago.

450

From the fossil record it appears that arthropod-like animals probably move onto land about _______ million years ago.

530

The endosymbiont theory explains the origin of

eukaryotic cells

Which scenario would be a modern example of Lamarckianism?

A son is born with a portion of his right index finger missing—the same portion that was severed from his father's hand in an accident.

A second individual who, like Darwin, suggested that natural selection could drive evolution was

Alfred Wallace

Which statement about gene mutations is FALSE?

All mutations are transmitted to the next generation

In Miller and Urey's reaction chamber experiment, what was the source of the nitrogen for the organic molecules that formed?

Ammonia

Which is the first eon for which there is evidence of life?

Archean eon

On which ship did Charles Darwin sail around the world?

Beagle

DNA is believed to have replaced RNA as the main information molecule because _____.

DNA is double-stranded and breaks less easily.

Which step in the evolution of life is the most complex and probably occurred last?

Formation of membrane-bound protocells

It is thought that by the mid-Cambrian, two supercontinents were present on Earth. These were

Gonwana and Laurentia

Four the following statements are true about the mitochondrion. Which statement is false?

It evolved from chloroplasts

Which is not a characteristic of LUCA?

It was the first cellular life.

Which of the following was not an advantage for an organism moving to land?

It's easier to support the body's mass without having to cope with water pressure.

Which of the following is a period within the Mesozoic Era?

Jurassic Cretaceous Triassic

The oldest fossils ____.

are buried deeper in the ground than newer forms

Darwin's ideas regarding evolution incorporated the ideas of many who came before him. The concept of a very old Earth shaped by gradual geologic forces derived from

NOT Thomas Malthus

In seed plants, an immature seed is called a(n)

NOT pollen grain

At the beginning of the Mesozoic Era Earth's landmasses are thought to have formed one supercontinent called

Pangea

The evolutionary line that has given rise to the mammals separated from the reptilian no later than the

Permian

Which of the following was an advantage for an organism moving to land?

Photosynthetic organisms were exposed to more light for their energy. There was less competition living on land. There were fewer predators on land. More oxygen was available in the air than in the water.

The study of the distribution of animals and plants around the world is ____.

biogeography

No convincing fossil evidence exists for ____.

catastrophism

The hypothesis that RNA served as the genetic information of early life is called _________________.

RNA world hypothesis

The outermost extraembryonic membrane that lies next to the shell is the

chorion

A taxonomist who only uses shared, derived characteristics could be considered to use a

cladistic approach

In a scientific context what does the term 'survival of the fittest' mean?

The organisms which are best adapted to their environment will survive the longest and have a greater number of offspring who are likely to inherit their advantageous traits

Darwin's ideas regarding evolution incorporated the ideas of many who came before him. The concept of populations sizes being limited by environmental capacity derived from

Thomas Malthus

Scientists began to question the perfection of the "great chain of being" partially because of their studies in ____.

comparative morphology

During the first portion of the Mesozoic, the forests of northern Pangea were largely composed of

conifers, ginkgoes and cycads

The organism known as Anomalocaris was

a large predator during the Cambrian

What event marks the beginning of the Mesozoic Era?

a mass extinction in which an estimated 95% of the species on Earth went extinct

The formation of amino acids under abiotic conditions was important because they serve as ____.

a supply of structural units for proteins

Which of the following is not an condition for the process of natural selection?

all individuals have an equal likelihood of survival

allopatric speciation

also known as geographic speciation, is speciation that occurs when biological populations of the same species become isolated due to geographical changes such as mountain building or social changes such as emigration.

The above illustration is of the bones in a human arm and the front leg of an elephant. These are called homologous structures because

although they serve different functions, they evolved from a common origin.

The above illustration is of the forelimbs of a cat, whale and bat. The bones in these limbs are called homologous structures because

although they serve different functions, they evolved from a common origin.

Trilobites are

an extinct group of arthropods

The first cells were ____.

anaerobic

There are two lakes 20 miles apart. Both lakes have a population of small plants called duckweed. Occasionally birds get the duckweed stuck to their feathers or feet and carry it to the other lake. This is an example of

gene flow between the two populations

A small population of individuals leaves the parent population and colonizes a new habitat. In this small population, traits which were not common in the parent population are frequently seen. This is probably the result of

genetic drift

In 2468, a shuttle containing 2 males and 3 females from the Enterprise crashed on a uninhabited class M planet. The colonists were not rescued by Picard. The colonists and their offspring randomly mated for many generations until the Enterprise-J rescued them several centuries later. All of the original colonists had free ear lobes (a dominant trait, the recessive trait is attached ear lobes). The genotypes for the original colonists were FF, FF, FF, Ff, and Ff. If two of the original colonists died before they produced offspring the ratios of genotypes could be quite different in the subsequent generations. This is an example of

genetic drift

During the first major divergence of life, the atmosphere was ____.

high in hydrogen, low in oxygen

The situation in which an embryo produced as a result of a mating between individuals of different species is incompatible with the mother and is subsequently aborted is an example of ____.

hybrid inviability

At the beginning of the Mesozoic, immediately after the Permian extinction, the land's surface was

largely prairie-like ecosystems composed of clubmosses and horsetails

All vertebrate tetrapods appear to have evolved from

lobe-fined fish

One key feature of Darwin's theory of natural selection was that

members of the same species show variability within a population

During the first portion of the Mesozoic, the forests of southern Pangea were largely composed of

now extinct plants known as seed ferns

Most consider that flowers with _______ floral parts represent the most primitive condition.

numerous

parapatric speciation

occurs when a smaller population is isolated, usually at the periphery of a larger group, and becomes differentiated to the point of becoming a new species.

Where are the Galapagos Islands located?

off the west coast of South America

Life probably would never have emerged on Earth if the ancient atmosphere had been the same as the present one in regard to the content of ____.

oxygen

A taxonomist who only uses the number of shared characteristics to classify organisms (sometimes called a numerical taxonomist) could be considered to use a

phenetic approach

Which group of mammals gives birth to the most developed offspring?

placental

Which animal group did not first evolve during the Cambrian Period?

placental mammals

What can result in speciation within a few generations?

polyploidy arising in a plant species

Chance events which may randomly alter allele frequencies are most likely to occur when

population size is small

adaptive radiation

process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, creates new challenges, or opens new environmental niches.

A membranous sac that contains interacting organic molecules, hypothesized to have formed prior to the earliest life-forms:

protocell.

In terms of natural selection, genetic variation is important in that it may

provide alternative phenotypes which may respond to the environment in different ways

Which of the following contribute to variation between individuals?

radiation, viruses, mutagenic chemicals, & transposons

In the population genetics simulation, simulation 1 where no mutation occurred, through 200 generations, how did the A1 allele frequency change in the populations of 800 (the lines of color)?

the A1 allele frequencies varied due to the size of the population

When determining where to place an organism in taxonomic ranks above the species level, biologists use

the best judgment of phylogenetic history

The sharp reduction of the gene pool and the numbers of a population through a severe epidemic is an example of ____.

the bottleneck effect

Phylogeny refers to

the evolutionary lineage of an organism

Aerobic respiration became established as a result of the evolution of ____.

the oxygen-producing pathway of photosynthesis

The idea that the same geologic processes, occurring over millions of years, have formed Earth's surface is known as ____.

uniformitarianism

The Hardy-Weinberg law is

useful in determining the extent to which a sexually reproducing population is evolving.

Differences among individuals of the same species are referred to as

variation

According to Darwin's theory of natural selection, the individuals that tend to survive are those that have

variations best suited to the environment

Which of the following is required for a population to be in Hardy-Weinberg equilibrium?

very large population, random mating, no mutation

The accumulation of free oxygen in the atmosphere ____.

was a result of the accumulation of a by-product of a type of photosynthesis

When would the effects of genetic drift be greatest?

when the population is small

Land plants are able to transport water from the roots in the soil to the above ground portions of the plant using

xylem vascular tissue.

The extraembryonic membrane that provides nutrition to the developing embryo is the

yolk sac