Module 4 Study Guide Bio 103

Why is only one strand of DNA transcribed into mRNA?

Because transcribing both DNA strands would produce different amino acid sequences

Beadle and Tatum irradiated Neurospora and initially grew the mutant strains on complete medium. How were they able to determine the type of mutation for each strain?

By growing the mold on minimal media supplemented with different combinations of amino acids and vitamins

Which statement about radioisotopes is FALSE?

Carbon-14 is typically used to date sedimentary rock.

In which group of islands Charles Darwin observed variation among organisms and compared these organisms to those found on the mainland?

Galapagos Islands

Adenine and thymine are held together by two hydrogen bonds in a double stranded DNA molecule. (T/F)

True

Membership in a clade cannot be established by shared ancestral traits alone. (T/F)

True

RNA interference is a process by which noncoding RNA molecules regulate gene expression. (T/F)

True

The poly-A tail is thought to facilitate the export of mRNA from the nucleus. (T/F)

True

The results in the accompanying figure support the conclusion that:

natural selection can occur in guppies within a few generations.

Beadle and Tatum began their studies with wild-type Neurospora. How is this organism best characterized?

A normal phenotype that will grow on minimal medium

Based on the accompanying figure, which two present day continents should have the most closely related plant and animal species?

Africa and South America

Whose findings of evolution by natural selection were presented with those of Darwin?

Alfred Wallace

Acquired variations that are favorable to the survival of an organism tend to be present in greater frequency in the next generation of those organisms.

False

An RNA primer is synthesized by RNA primase. (T/F)

False

One of the pyrimidine bases in a DNA molecule is adenine. (T/F)

False

Why is DNA able to store large amounts of information?

Its nucleotides can be arranged in many possible sequences.

What are special enzymes that recognize and remove the incorrectly paired nucleotides in DNA?

Mismatch repair

Which of the following consists of short, noncoding, guanine-rich DNA sequences that repeat many times?

Telomere

Fossil evidence shows that giraffes living 1000 years ago had much shorter necks than the giraffes seen today. Which statement best explains this observation?

The giraffes acquired longer necks through the continuing process of natural selection.

During protein synthesis, ribosomes:

attach to the mRNA molecule and travel along its length to produce a polypeptide

Table 18-1 Species Pairs Percent Divergence in a Selected DNA Sequence Human−chimpanzee 1.7 Human−gorilla 1.8 Human−orangutan 3.3 Human−gibbon 4.3 Human−rhesus monkey 7.0 Human−spider monkey 10.8 Human-tarsier 24.6 ​ Based on data in the accompanying table, which primate has the most recent common ancestor with humans?

chimpanzee

Phylogenetic systematics produce branching diagrams called:

cladograms

The genetic code is sometimes called "universal," meaning that all organisms share the same:

coding mechanism

What mechanism would explain how fossils of the same organism can be found in parts of Africa and South America?

continental drift

In DNA replication, the lagging strand

is synthesized as a series of Okazaki fragments.

tRNA molecules are able to act as adapters between amino acids and mRNA during translation because:

tRNA can bind to both mRNA and an amino acid.

The molecule that connects a growing polypeptide chain and mRNA is called:

tRNA.

Which classification level contains the greatest number of species?

Domain

The two strands of a DNA double helix can be described as running parallel to each other. (T/F)

False

What is the land mass labeled as 2 in the accompanying figure?

Gondwana

Which important finding from the fossil record supports the theory of evolution?

Life has evolved over time.

Who first confirmed that the replication of DNA was semiconservative?

Meselson and Stahl

How many different kinds of amino acids are known?

More than 20

How does the first nucleotide at the 5′ end of a new mRNA chain differ from the other nucleotides in the chain?

The first nucleotide retains its triphosphate group, while the others do not.

You have identified a new mammal species. You are surprised to find that it has a pelvis, but there is no evidence the species has legs. What can you conclude about this animal's structure?

The pelvis is a vestigial structure.

Choose the best match for the definition. Taxonomy Classification Cladogram Systematics Phylogeny

The science of naming, describing and classifying organisms The arrangement of organisms into groups based on similarities that show evolutionary relationships A group of organisms with a common ancestor The scientific study of the diversity of organisms and their evolutionary relationships The evolution of a group of organisms from a common ancestor

Two species have homologous structures. What can we infer?

The species are related by a common ancestry.

Who originally published the idea that food supplies, which sustain animal populations, have the capacity to increase arithmetically?

Thomas Malthus

How many domains form the three main branches of the tree of life?

Three

Signal-recognition particle RNA is involved in directing the ribosome-mRNA-polypeptide complex to the rough ER.

True

Which example illustrates how "maximum likelihood" is used by systematists?

Using probability to determine that the nucleotide sequences in DNA and RNA change at a constant rate over time

Scientists using evolutionary systematics to construct a phylogenetic tree would use:

a combination of ancestral and derived characters.

What is a cladogram?

a diagram showing lines of descent

The term "clade" most closely refers to:

a group of organisms that share common characteristics inherited from a common ancestor.

Which of the following would be least likely to form a fossil?

an organism in the tropical rain forest

An example of homologous structures is the wing of a bat and the:

arm of a human.

The rapid evolution of bacteria and fungi in certain environments is used in the field of:

bioremediation

MIT and Harvard have sequenced the genome of domestic _________.

dogs

In the late 1970s, Woese argued that there are two fundamentally different groups of prokaryotes by demonstrating:

gene codes of ribosomal RNA of different bacteria.

Which are evolutionary modifications that improve the survival and reproductive success of an organism?

homoplastic traits

Which of the following is made from DNA?

mRNA, tRNA, and rRNA

Primase is the enzyme responsible for

making short strands of RNA at the site of replication initiation.

A taxon that includes all the descendants of an ancestor is called:

monophyletic.

The differential distribution of wing length in Drosophila, with larger wings in northern areas and smaller wings in southern climates, provides evidence that:

natural selection is the most important agent in evolutionary change.

A ____ mutation results in the conversion of a codon specifying an amino acid to a termination codon.

nonsense

The information encoded by the DNA is specified by the

nucleotide sequence of the DNA molecule.

The evolutionary history of a group of organisms from a common ancestor is known as:

phylogeny.

RNA is ____ and contains the nitrogenous base ____, which is absent in DNA.

single stranded; uracil

The scientific study of the diversity of organisms and the evolutionary relationships between them is referred to as:

systematics

A study of the genomes of dogs from around the world indicated that:

the dogs' closest relative is the gray wolf.

Which is an example of convergent evolution?

the elongated snouts of aardvarks, anteaters, and pangolins

The experimental design in the accompanying figure was used to examine:

the relationship between genetic changes and metabolic enzymes.

The first scientists to use Griffith's transformation assay to identify genetic material were

Avery, MacLeod, and McCarty.

Which is the third kingdom to be established to accommodate bacteria and other microorganisms?

Cryptogamae

Refer to the accompanying figure. The average weight of a female guppy in the experimental group is:

190 mg

How long age was the time of Aristotle?

2200 years ago

A ribosome has one binding site for mRNA and two binding sites for tRNAs.

False

In eukaryotes, the initiator tRNA carries the amino acid leucine. (T/F)

False

Molecular chaperones assist in the folding of newly synthesized mRNAs. (T/F)

False

Okazaki fragments are complementary to the leading strand of DNA. (T/F)

False

Replication typically occurs at a single origin of replication in eukaryotic chromosomes. (T/F)

False

The decrease of carbon-12 in a fossil indicates the age of that fossil. (T/F)

False