Chapter 25 study question

How are conditions on the early Earth of more than 3 billion years ago different from those on today's Earth?

only early Earth was intensely bombarded by large space debris

An organism has a relatively large number of Hox genes in its genome. Which of the following is true of this organism?

organism has a genetic potential to have a relatively complex anatomy

The major evolutionary episode corresponding most closely in time with the formation of Pangaea was the

Permian Extinction

Which of the following factors weakened the hypothesis of abiotic synthesis of organic monomers in early Earth's atmosphere? 1 the relatively short time between intense meteor bombardment and the appearance of the first life forms 2 a lack of experimental evidence that organic monomers can form by abiotic synthesis 3 uncertainty about which gas has compromised early Earth's atmosphere

1 and 3

Which of the following characteristics should have been possessed by the first animals to colonize land? 1. we're probably herbivores 2. had four appendages 3. have the ability to resist dehydration 4. had lobe-finned fishes as ancestors 5. were invertebrates

1, 3, and 5

Which of the following is the correct sequence of events in the origin of life? 1. Formation of Protobionics 2. synthesis of organic monomers 3. synthesis of organic polymers 4. formation of DNA based genetic systems

2 ,3,1,4

The first terrestrial organisms probably were considered which of the following? 1. burrowers 2. photosynthetic 3. multicellular 4. prokaryotes 5. eukaryotes 6. plants and their Associated fungi

2 and 4

Is natural selection in a particular environment favored genetic systems that permitted the production of daughter "cells" that were genetically dissimilar from the mother "cells", then one should expect selection for which of the following? 1 polynucleotide polymerase with low mismatch error rates 2 polynucleotide polymerase without proofreading capability 3 batteries of efficient polynucleotide repair enzymes 4 polynucleotide polymerase with proofreading capability 5 polynucleotide polymerase with high mismatch error rates

2 and 5

If you half-life of carbon-14 is about 5730 years, in a fossil that has one-sixteenth the normal proportion of carbon-14 to carbon-12 should be about how many years old?

22,900

Approximately how far back in time does the fossil record extend?

3.5 billion years

What is thought to be the correct sequence of events, from earliest to most recent, in the evolution of life on Earth? 1. Origin of mitochondria 2. origin of multicellular eukaryotes 3. origin of chloroplasts 4. origin of cyanobacteria 5. origin of fungal plant symbiosis

4, 1, 3, 2, 5

First genes on Earth were probably

Auto catalytic RNA molecules

Which event is nearest in time to the end of the period known as snowball Earth?

Cambrian explosion

Several scientific Laboratories across the globe are involved in research concerning the origin of life on Earth. Which of these questions is currently the most problematic and would have the greatest impact on our understanding if we were able to answer it?

How did RNA sequences come to carry the code for amino acid sequences?

Bagworm moth caterpillars feed on evergreens and carry a silicon case or bag around with them and which eventually pupate. Adult female bagworm moth larvae in appearance; they lack the wings and other structures of the adult male and instead retain the appearance of a caterpillar even though they're sexually mature and can lay eggs with in the bag. This is a good example of

Paedomorphosis

What measurements would help determine absolute dates by radiometric means?

The accumulation of the daughter isotope & loss of parent isotopes

Which of these observations gives the most support to the endosymbiotic theory for the origin of eukaryotic cells?

The similarity in size between the cytosolic ribosomes of prokaryote and the ribosomes within mitochondria and chloroplasts

If two continents converge and are united, then the collision should cause

a net loss of intertidal zone in coastal habitat

An early consequence of the release of oxygen gas by plant and bacterial photosynthesis was to

cause iron in ocean water and terrestrial rocks to oxidize

If a fossil is encased in a stratum of sedimentary rock without any strata of igneous rock nearby then it should be

difficult to determine the absolute age of a fossil, because radiometric dating a sedimentary rock is less accurate than that of igneous rock

The snowball Earth hypothesis provides a possible explanation for the

diversification of animals during the late proterozoic era

The synthesis of new DNA requires the prior existence of oligonucleotides to serve as primers. on Earth, these primers are small RNA molecules. this latter observation is evidence in support of the hypothesized existence of

earlier genetic systems then those based on DNA

The existence of the phenomenon of exaptation is most closely associated with which of the following observations that natural selection cannot fashion perfect organisms

evolution is limited by historical constraints

One explanation for the evolution of insect wings just that wings began as lateral extensions of the body that uses heat dissipators for thermoregulation. When they had become sufficiently large, these extensions became useful for gliding through the air, and selection later refined them as flight producing wings. If this hypothesis is correct, modern insect wings could best be described as

exaptations

Fossil evidence indicates that several kinds of flightless dinosaurs possessed feathers. If some of these feather bearing dinosaurs incubated clutches of eggs and carefully constructed nests, this might be evidence supporting the claim that

feathers originally served as insulation, and only later becoming flight surfaces

On the basis of their morphologies, how might Linnaeus have classified the Hawaiian silverswords?

he would have placed them in more species than modern botanists do

The existence of evolutionary trends, such as increasing body sizes among horse species, is evidence that

in particular environments, similar adaptations can be beneficial in more than one species

What is true of the fossil record of mammalian organisms?

it includes transitional forms with progressively specialized teeth

Recent evidence indicates that the first major diversification of multicellular eukaryotes may have coincided in time with the

melting that ended the snowball Earth.

What is true of the Cambrian explosion?

recent evidence supports the contention that the Cambrian explosion may not have been as explosive as was once thought

The loss of ventral spines by modern freshwater sticklebacks is due to Natural Selection operating on the phenotypic effects of pixel 1 Gene

silencing( loss of expression)

In the five to seven million years that the hominid lineage has been diverging from its common ancestor with the great apes, dozens hominid species have arisen, often with several species coexisting in time and space. As recently as 30,000 years ago, Homo sapiens coexisted with homo neanderthalensis. Both species had large brains and advanced intellect. The fact that these traits were common to both species is most easily explained by which of the following?

species selection

Many species of snakes lay eggs. However, in the forests in northern Minnesota where growing seasons are short, only live bearing snakes species are present. This trend towards species that perform life birth in a particular environment is an example of

species selection

What is true of amino acids that might have been delivered the Earth Within carbonaceous chondrites?

there were more kinds of amino acids on the chondrites then are found in living organisms today

If one organ is an exaptation of another organ, then what must be true of these two organs?

they are both homologous organs

In order to properly interpret sediment cores, it is necessary to apply the principle of

superposition

Which of the following is a defining characteristic that all protobionts had in common?

surrounding membrane or membrane like structure

Which of the following statements provides the strongest evidence that prokaryotes evolved before eukaryotes?

the oldest fossilized cells resemble prokaryotes

Maggots express ubx gene in all of their segments, and thereby lack appendages. If this same gene continue to be expressed throughout subsequent developmental stages, except in the head region, and if the result was a fit, sexually mature organism that still strongly resembled a maggot, this would be an example of

two of the responses above are correct