Ch. 11 & 12 Review

vector

gene carrier

primers

short chemically synthesized single-stranded DNA molecules with sequences that are complementary to sequences at each end of the target sequence

HGP (Human Genome Project)

had the goals of determining the nucleotide sequence of all DNA in the human genome and identifying the location and sequence of every gene.

embryonic stem cells

harvested from the blastocyst

gene cloning

the production of multiple identical copies of a gene-carrying piece of DNA

reverse transcriptase

the researcher isolates the mRNA and makes single-stranded DNA transcripts from it using enzymes

gene regulation

the turning on and off of genes

RFLP (restriction fragment length polymorphism) analysis

a sequence variation of this type

genetically modified organism (GMO)

organisms that have acquired one or more genes by artificial means.

differentiation

process in which cells become specialized in structure and function with each type of cell fulfilling a certain role

therapeutic cloning

produce embryonic stem cells for therapeutic treatments

Place where RNA polymerase begins transcription:

promoter

plasmids

small circular DNA molecules that replicate separately from the bacterial chromosome

A short sequence of DNA nucleotides that repeats one after the next is known as which of the following? a. STR b. PCR c. CODIS d. DNA

a. STR

DNA ligase

joins the two DNA molecules by colvalent bonds

activators

proteins that turn operons on by binding to DNA

Forensics

scientific study of crime scene evidence

Ti plasmid

the most common vector used to introduce new genes into plant cells is a plasmid from the soil bacterium

alternative RNA splicing

An organism can produce more than one type of polypeptide from a single gene

proteomics

study of the structure and function of proteins in the human body

epigenetic inheritance

Inheritance of traits transmitted by mechanisms not directly involving the nucleotide sequence.

regeneration

regrowth of lost body parts

vaccine

A harmless variant or derivative of a pathogen that stimulates a host's immune system to mount defenses against the pathogen

Whole-genome shotgun method

A method for determining the DNA sequence of an entire genome. After a genome is cut into small fragments, each fragment is sequenced and then placed in the proper order.

restriction fragments

In this case the restriction enzyme cuts each DNA strand between the bases A and G within sequence producing pieces of DNA

gel electrophoresis

Procedure used to separate and analyze DNA fragments by placing a mixture of DNA fragments at one end of a porous gel and applying an electrical voltage to the gel

short tandem repeat (STR)

a DNA sequence consisting of a short sequence of nucleotides (usually 2 to 5 nucleotides in length) repeated multiple times, with all of the repetitions side by side on a chromosome; variations in the number of repeats of a standardized set of 13 STRs produce DNA profiles used to identify people by their DNA

STR analysis

a method of DNA profiling that compares the lengths of STR sequences at specific sites in the genome

SNP (single nucleotide polymorphism)

a single base-pair site where variation is found in at least 1% of the population

polymerase chain reaction (PCR)

a technique by which a specific segment of a DNA molecule can be targeted and quickly amplified in the labratory

gene therapy

alteration of an afflicted individual's genes for therapeutic purposes.

repetitive DNA

consits of nucleotide sequences that are present in multiple copies in the genome

nucleic acid probe

it is used to find a specific gene or other nucleotide sequence within a mass of DNA

complementary DNA (cDNA)

represents only the subset of genes that had been transcribed into mRNA in the starting cells

genomics

study of whole genomes, including genes and their functions

restriction site

the DNA sequence recognized by a particular restriction enzyme

DNA profilling

the analysis of DNA samples to determine whether they came from the same individual

restriction enzymes

the cutting tools are bacterial enzymes

geonmic library

the entire collection of all the cloned DNA fragments from a genome

repressor

transcription is turned off by a protein called

A corn plant that has a gene from a bacterium inserted into it would be considered a(n)...

transgenic organism.

List two concerns that GMO critics have of GMO products.

1. GMO crops could pass their new genes to close relatives in nearby wild areas. It could create a super weed that is hard to control. 2. If GMO crops become less naturally genetic then die-offs could happen from environmental changes.

List the key events of a signal transduction pathway.

1. Signaling cell secretes a signaling molecule 2. The molecule binds to a receptor protein embedded in the target cell's plasma membrane 3. The binding activates the first in a series of relay proteins within the target cell 4. The last relay molecule in the series activates a transcription factor 5. Triggers transcription of a specific gene 6. Translation of the mRNA produces a protein.

STR analysis used for DNA profiling in the pursuit of a criminal or legal matter requires that... STR sites be compared.

13 predetermined

A segment of DNA is known to have three restriction sites for a particular restriction enzyme. An SNP has occurred in the middle restriction site that causes it to no longer be recognized by the restriction enzyme. When the DNA is separated by gel electrophoresis, there will be ... bands of DNA visible.

3

What percentage of the human genome consists of repetitive sequences of DNA? Refer to Figure 12.18 on page 248 of your textbook.

44% is repetitive DNA that includes transposable elements and related sequences. 15% is repetitive DNA unrelated to transposable elements. Together 59% of the human genome consists of repetitive sequences.

signal transduction pathway

A series of molecular changes that converts a signal on a target cell's surface to a specific response inside the cell.

Adult stem cells

Able to give rise to many but not all cell types in the organism.

Refer to Figure 12.12 on page 243 of your textbook. How many DNA sequences are there after five cycles? How long did that take if each cycle took 30 minutes?

After 5 cycles there will be 32 DNA sequences. It took 150 minutes or 2.5 hours for 5 cycles to happen.

A sieve is a device used to separate solids from liquids. On page 243 of your textbook, module 12.13, the authors state, "Because agarose contains a tangle of cable-like threads, it can act as a molecular sieve." Briefly explain this analogy.

Agarose is like a sieve because it filters the DNA. It separates the DNA by size. The smaller fragments can travel faster and the larger travel slowly through the agarose.

Briefly explain what is meant by the following statement: All transgenic organisms are GMOs, but not all GMOs are transgenic organisms.

All transgenic organisms are GMOs because their DNA is altered by a different species gene. Not all GMOs are transgenic organisms because their DNA is not altered by a different species gene.

clone

An organism that is genetically identical to the organism from which it was produced asexual

The use of organisms or their products for human purposes:

Biotechnology

A molecule that facilitates the formation of covalent bonds between nucleotides:

DNA ligase

A set of techniques for manipulating DNA:

DNA technology

True or false: A mutation in a homeotic gene does not affect which end of the fly becomes the head. If false, make it a correct statement.

False, does affect.

True or false: miRNAs are small sequences of RNA that bind to complementary sequences of DNA to inactivate a gene. If false, make it a correct statement.

False, miRNAs are small RNA molecules that bind to complementary sequences on mRNA molecules. It degrades the target mRNA and blocks its translation.

True or false: The expression of genes can be turned on or off. If false, make it a correct statement.

False, the process in which genes can be turned on or off is gene regulation.

Purposefully altering genes for human purposes:

Genetic engineering

Briefly state what the purposes of the Human Genome Project (HGP) were.

HGP purpose was to find the nucleotide sequence of all DNA in the human genome and identify the location and sequence of every gene. THe benefits from this can help identify diseases and help with the making of medicine.

Embryonic stem cells

Harvested from the blastocyst. Give rise to all the different kinds of specialized cells of the body.

...determines which end of the fruit fly becomes the head.

Homeotic gene

What would you expect to be true about the genomes of two species that evolved away from each other a million years ago?

If two species evolved away from each other a million years ago some DNA would be similar. It would help us understand more ancient evolutionary history.

List the steps of nuclear transplantation.

Involves replacing the nucleus of an egg cell or a zygote with the nucleus of an adult somatic cell. The recipient cell begins to divide. About 5 days later the repeated cell divisions form a blastocyst. Then the blastocyst can be used for different purposes.

Briefly explain why control valves on a water pipe are a good analogy for control of gene expression in eukaryotes.

It is a good analogy because gene regulation occurs in many different places. Also the more you turn a valve the more water comes out like the methyl group. It turns on the gene. But if you shut off the valve the water stops, like the methyl group not being added.

Ideally, a person would get ES cells made from one of his or her own donated somatic cells. Briefly explain why this is so advantageous.

It is advantageous because they are your cells so the DNA matches. The organ you created would not be rejected.

What does the fact that many organisms on earth share similar mechanisms of signal transduction mean with respect to evolution?

It means that cell signaling evolved early in the history of life.

A scientist trying to clone a Bengal tiger via nuclear transplantation obtains the donor nucleus from a gametic cell rather than a somatic cell. Briefly explain why this is not going to work.

It will not work because gametic cells contain a haploid set of chromosomes.

People usually assume that the human genome is the largest in terms of size and number of genes. Is this true? Cite specific examples in your answer. Refer to Table 12.17 on page 247 of your textbook.

No, humans do not have the largest genome. According to the chart four other organisms have more genes than humans. The chart shows that Xenopus tropicalis (frog) have the most genes.

The human genome consists of about 21,000 genes spread across 24 different chromosomes. Do men and women have the same number of different genes? Briefly explain your answer.

No, men and women don't have the same number of different genes. Women have more genes because the X chromosome has more genes than the Y chromosome.

A graduate student working in a molecular biology laboratory sets up an agarose gel so that the wells that contain the DNA are at the positive end of the power source. Did she load the gel correctly? Briefly explain what will happen.

No, she loaded the gel incorrectly. If she does this the DNA won't go anywhere. It is attracted to the positive side because of its negative charge.

A round bacterial chromosome:

Plasmid

DNA combined from two different sources:

Recombinant DNA

Briefly explain why scientists may not want to eliminate disease-causing alleles from the human population.

Scientists may not want to eliminate disease-causing alleles because it could backfire. It can cause more problems and those alleles could be beneficial in the future.

Protein activation

Some polypeptides require alterations before they become functional. EX: Hormone insulin is a protein. Insulin is synthesised in the cells of the pancreas as one long polypeptide that has no hormonal activity. After translation the form of insulin that functions as a hormone.

Briefly explain how the inactivation of the X chromosome in human females is an example of epigenetics.

The X chromosome will be inactivated and all cellular descendants will have the same inactivated chromosome. This shows that it is epigenetics because it is inheritance not directly involving nucleotide sequence.

genetic engineering

The direct manipulation of genes for practical purposes.

A geneticist working for the National Institutes of Health (NIH) discovers a rare mutation of a human gene that leads to a high degree of methylation on the male Y chromosome. Briefly explain what effect this might have on gene expression on the Y chromosome.

The effect of this mutation on the Y chromosome would mean the genes are less likely to be expressed.

Protein breakdown

The final control mechanism operating after translation is the selective breakdown of proteins. EX: Some of the proteins that trigger metabolic changes in cells are broken down within a few minutes or hours. This regulation allows a cell to adjust the kinds and amounts of its proteins in response to changes in its environment.

biotechnology

The manipulation of living organisms or their components to produce useful products.

List three reasons why bacteria are great organisms for the mass production of desirable protein products.

The plasmids and phages available for use as gene-cloning vectors. The fact that bacteria can be grown rapidly and cheaply in large tanks. Bacteria can be engineered to produce large amounts of particular proteins and sometimes secrete the proteins directly into the growth medium, simplifying the tasks.

Initiation of translation

The process of translating an mRNA into a polypeptide also offers opportunities for regulation. EX: Red blood cells have an inhibitory protein that prevents translation of hemoglobin mRNA unless the cell has a supply of heme.

Briefly explain the genetic relationship between the two carrot plants in Figure 11.12 on page 221 in your textbook.

The relationship between the carrot plants was through asexual reproduction, a clone was produced.

A cell has a mutation that causes a shape change in a cell-surface receptor protein that binds a signaling molecule. What effect is this likely to have on that particular signal transduction pathway?

The signaling molecule won't bind with the receptor protein and the pathway will be blocked.

A crime scene technician obtains a single hair from the scene of a bank robbery. What will the technician do in order to get enough DNA from the hair to analyze?

The technician will use the method of polymerase chain reaction to get more DNA.

True or false: An SNP can occur in either a gene or noncoding sequence of the human genome. If false, make it a correct statement.

True

True or false: DNA profiling involves the analysis of two separate DNA samples to determine whether or not they came from the same person. If false, make it a correct statement.

True

True or false: Genes that are unexpressed retain the ability to be expressed. If false, make it a correct statement.

True

True or false: Plasmids are crucial in gene cloning because they can carry almost any gene. If false, make it a correct statement.

True

Table 12.6 on page 237 of your textbook lists numerous protein products and the organisms that produce them. Tissue plasminogen activator (TPA) is not made by E. coli or S. cerevisiae. What are you able to infer about TPA?

You can infer the TPA needs sugar chains added to it to work and E. coli and S. cerevisiae can't do that. So mammalian cells are able to do the job.

operon

a cluster of genes with related functions along with the control sequence

histones

a crucial aspect of DNA packing is the association of the DNA with small proteins

promoter

a site where the transcription enzyme, RNA polymerase, attaches and initiates transcription

Which of the following is a sequence of DNA that resides far away from the gene it helps to control? a. Enhancer b. Barr body c. Transcription factor d. Promoter

a. enhancer

cD it does affect.NA is made from ____________ using reverse transcriptase. a. mRNA b. DNA c. cDNA d. miRNA

a. mRNA

adult stem cells

able to give rise to many but not all cell types in the organism

A protein that binds to DNA and stimulates transcription:

activator

nuclear transplantation

animal cloning can be achieved through a procedure called

Which of the following explains why mammalian cells are sometimes needed to produce protein products? a. E. coli cannot make certain genes because the DNA language of certain human genes is different. b. Certain mammalian proteins need sugar chains added to them and only mammalian cells can do this. c. Many human genes require a special ribosome found only in mammalian cells. d. Simple organisms, like bacteria, lack the ability to synthesize complex human genes.

b. Certain mammalian proteins need sugar chains added to them and only mammalian cells can do this.

Which of the following explains why DNA from two different sources can be joined together as long as they were cut with the same restriction enzyme? a. The restriction enzyme forms hydrogen bonds with the DNA. b. The bases at the sticky ends will be complementary to each other. c. DNA ligase recognizes that the two sources of DNA were cut with the same enzyme and joins the fragments. d. The restriction fragments will be the exact same length, which allows the two fragments to join

b. The bases at the sticky ends will be complementary to each other.

operator

between the promoter and the enzyme genes a DNA control sequence (acts as a switch)

Which of the following results in stem cells that can be used in treating medical ailments? a. Reproductive cloning b. Regeneration c. Therapeutic cloning d. None of the above

c. Therapeutic cloning

microRNA

can bind to comlementary sequences on mRNA molecules

An organism produced from a single parent is referred to as a(n)...

clone

nucleosome

consists of DNA wound around a protein core of eight histone molecules.

Which of the following is a use of DNA technology? a. Pinpoint viral infections b. Develop vaccines c. Produce products for therapy d. All of the above

d. All of the above

Which of the following does not occur in the nucleus of a eukaryotic cell? a. Methylation b. Alternative RNA splicing c. Regulation of transcription d. RNA interference

d. RNA interference

The process by which a cell becomes specialized in structure and function is called...

differentiation.

mRNA breakdown

enzymes in the cytoplasm eventually break them down. The timing helps with regulating the amounts of various proteins that are produced in the cell. EX: Long lived mRNA is found in vertebrate red blood cells.

Recombinant DNA

formed when scientists combine nucleotide sequences from two different sources, often different spieces, to form a single DNA molecule

The replacement of a person's disease-causing genes with functional genes is known as...

gene therapy.

Rather than comparing the genomes of two samples, researchers can compare ... which are sequences within the human genome that vary from person to person.

genetic markers

An entire collection of cloned DNA pieces that consists of an organism's genome is known as a(n)...

genomic library.

The study of entire sets of genes and their interactions is referred to as ...

genomics.

RNA interference

injecting miRNA into a cell can turn off expression of a gene with a sequence that matches the miRNA the procedure is called

DNA microarray

is a glass slide with tiny amounts of thousands of different kinds of single stranded DNA fragments fixed to it in tiny wells in a tightly spaced array or grid.

X chromosome inactivation

is initiated early in embryonic development, when one of the two X chromosomes in each cell is inactivated at random.

regulatory gene

located on the operon, codes for the repressor

DNA technology

modern laboratory techniques for studying and manipulating genetic material

The default state of most eukaryotic genes is...

off

DNA sequence that determines whether RNA polymerase binds the promoter:

operator

Genes that serve a related function and the sequences that control them:

operon

A research biologist assembles a list of all the proteins produced by a certain spider found in the Amazon. He uses this list to study the interactions of certain proteins of interest. This scientist is using an approach called ...

proteomics.

Protein that blocks the RNA polymerase from binding the DNA:

repressor

reproductive cloning

results in the birth of a new living individual

gene expression

the overall process by which genetic information flows from genes to proteins