BIO 121 chapter 18 Genome

Vertebrates have more noncoding DNA sequences.

What factor accounts most for the difference in genome size between vertebrates and prokaryotes?

Replacing the FOX2P gene in mice with a humanized version of the gene had no negative effects on the mice but did lead to the development of brain cells in neural circuits that are associated with speech development in humans.

Which of the following best describes the experimental evidence that the FOXP2 gene is vital to the normal development of vocalization in vertebrates and yet has evolved among different vertebrate lineages?

90% of the region was transcribed into different types of RNA

Which of the following best describes the findings of the ENCODE pilot study that thoroughly studied the makeup of a 1% region of the human genome?

Barbara McClintock

Who discovered "jumping genes" (transposons)?

genetic variation between breeds may be linked to phenotypic variation

Why might a dog genome sequencing project prove particularly informative, compared to other mammalian genomes?

Individuals with active transposons are usually eliminated by natural selection, because transposition events usually produce harmful mutations.

Why might active transposons be rare in natural populations?

create knockout mice to determine their phenotype.

A gene family has been identified that has undergone extensive duplication in humans, but is present in only one or a few copies in other primates or other mammals. What experimental approaches could be used to determine the function of this gene and its significance in human evolution?

what genetic differences may be responsible for the superior abilities of modern humans to communicate and make more sophisticated tools

A group of scientists is attempting to sequence the Neanderthal genome with DNA extracted from Neanderthal bones. Information from this project might reveal __________.

exon duplication and shuffling

A rapid way for natural evolution to alter a protein-coding gene so it encodes a protein with a different structure and function is __________.

Alternate splicing of RNA transcripts, post-translational cleavage of a polypeptide into active forms, regulation of gene expression by miRNA's, post-translation addition of carbohydrates to polypeptides...all of the listed responses are correct.

Although containing the same number of genes as the nematode genome, the human genome is thought to bear greater phenotypic diversity by means of __________.

are derived from or related to transposable elements.

Alu elements __________.

determine how insulin resistance affects transcription of thousands of other genes in the genome

An example of a systems biology experiment might be __________.

evolved from a common globing gene ancestor that gave rise to both alpha and beta globing genes, as well as myoglobin and plant leghemoglobin.

The molecular data indicate that the globin gene family __________.

of the common ancestry of different life-forms

The similarity of the homeobox in many different kinds of organisms is evidence __________.

using molecular biology to combine DNA from two different sources in a test tube

Bioinformatics includes all of the following EXCEPT __________.

chromosome rearrangements lead to gene duplication, thus generating a "spare" copy of the gene that is free to evolve and acquire a new function.

Chromosomal rearrangements may be important in evolution because __________.

most differences are in the form of chromosomal rearrangements

Detailed comparison of the human and chimpanzee genomes has revealed that __________.

40,000 base pairs

Given that about 25% of the mammalian genome is associated with genes, including introns and regulatory sequence, what would be the approximate average length of DNA per gene, if the genome contained 20,000 genes?

a. encode transcription factors that control the expression of genes responsible for specific anatomical structures.

Homeotic genes __________.

errors during DNA replication and recombination

Multigene families arise as a result of __________.

BLAST, a database of protein structures, genbank...all of the following are correct

NCBI provides __________.

they code for an enzyme that synthesizes DNA using an RNA template.

One of the characteristics of retrotransposons is that __________.

Retrotransposons

Segments of eukaryotic DNA that can move from one site to another in the genome by means of an RNA intermediate are called __________.

occupy much longer stretches of DNA than SNPs, and are likely to have greater phenotypic consequences

The advantage of copy-number variants (CNVs) over SNPs in human genomic studies is that CNVs __________.

homoeobox

The highly conserved sequence element present within homeotic genes is called the

20,000-25,000 genes

The human genome is thought to contain about how many genes?

alternative splicing

Two eukaryotic proteins are identical except for one domain in each protein, and these two domains are completely different from each other. Which of the following processes is most likely to have contributed to this difference?

exon shuffling

Two eukaryotic proteins have one domain in common but are otherwise very different. Which of the following processes is most likely to have contributed to this similarity?

Conserved genes provide insight into their evolutionary relationships.

What can be learned from comparing the genomes of distantly related species, such as yeast and humans, or plants and fruit flies?

Many genes undergo alternative splicing, so that different proteins with different exon combinations are produced from the same gene

Why might the number of genes in the genome underestimate the number of different proteins that an organism makes?