General Biology II Finals

Which of the following technique is used to identify the location of specific mRNAs in an intact organism?

in situ hybridization

A scientist is trying to identify the function of a novel gene. What would be the most accurate method to analyze how much this gene is expressed during different stages of development?

RT-PCR

Which of the following descriptions about genetically engineered agricultural products is not correct?

CRISPR-Cas9 is commonly used to introduce foreign genes into crop plants

Which of the following description ab out iPS cells is not correct?

Diseased cells are isolated from patients and converted to ‘cured’ iPS cells.

What is one of the major reasons eukaryotic cells are used to express some human genes in place of bacterial cells?"

Some eukaryotic proteins do not fold correctly in bacterial cells.

Which of the following descriptions about RNA-seq is not correct?

All types of RNA expressed in the cell can be identified using oligo dT primers for RNA-seq

Which of the following descriptions about microarray is not correct?

The oligonucleotides on the DNA chip are labeled with specific colors prior to hybridization

Which of the following descriptions about DNA cloning is not correct?

Restriction enzymes often make sticky ends such that DNA ligase is not required for cloning.

Which of the following cells is pluripotent but not totipotent?

embryonic stem cells

Which of the following description is correct?

STR and SNP are both examples of polymorphism

Which of the following prevents the expression of specific genes?

RNA interference

In a certain type of high-throughout, next-generation sequencing method, cycles of sequentially adding the four DNA nucleotides to all templates are repeated. Here, a flash of lights is detected when the nucleotide joins to the growing new strand, and if the nucleotide added next is not complementary, no light would be detected. What is the main reason light is detected in this method when a complementary nucleotide is added on?

Because the pyrophosphate that is released when nucleotides attach is used to produce light.

Which of the following is involved in the nourishment, insulation, and support for neurons?

glial cells

Which most accurately explains how heat is produced through nonshivering thermogenesis in brown adipose tissue?

The mitochondria produce heat instead of generating ATP. 

What is a main difference between positive and negative feedback control in homeostasis?

Positive feedback responses are in the same direction as the initiating stimulus rather than opposite to it.

Which of the following descriptions about connective tissue is correct?

The rubbery texture of cartilage is largely due to chondroitin sulfate.

Which of the following correctly explains convergent evolution found in several marine animals?

During evolution, the body shape of many marine animals are optimized to reduce drag while swimming.

Which of the following descriptions about countercurrent heat exchange in animals is not correct?

In cold conditions, blood flow in the skin decreases and that in the core of the body increases.

Which of the following would least likely occur at very low external temperatures?

increase in saturated fatty acid membrane phospholipids

Which of the following is correct?

A regulator uses internal control mechanisms to moderate internal change in the face of environmental fluctuations.

Which most accurately explains heat loss when cold wind is blowing on your skin during the winter?

convection

Which type of epithelium is commonly found in surfaces subject to abrasion, such as the linings of the mouth?

stratified squamous epithelium

Which of the following best describes the purpose of vaccination?

generation memory B cells and T cells against antigen

Helper T cells trigger both humoral and cell-mediated immune responses. Which does not correctly describe how this is achieved?

B cells are activated by signaling molecules from activated helper T cells, and the direct binding of its receptors to antigens.

Which of the following descriptions about the complement system is correct?

It promotes lysis of pathogens and attracts phagocytes to the site of infection.

HIV infection can lead to acquired immunodeficiency syndrome (AIDS), where the acquired immune response to antigens is absent due to the lost of function of its host cells. Based on these facts, what would most likely be the host cell for HIV?

helper T cells

Which of the following descriptions about antigen presentation is not correct?

B cells can bind to a specific antigen and display this antigen on its surface via its receptor.

Which of the following descriptions about memory cells and effector cells is correct?

the effector cells of B cells are plasma cells

Which of the following would most likely be detected by Toll-like receptors in mammals?

flagellin

Which of the following cells are nonphagocytic cells that detect surface proteins of abnormal cells and release chemicals that cause cell death?

natural killer cells

Which of the following is not a type of innate immunity in vertebrates?

antibodies

Which of the following descriptions about B cell antigen receptors is not correct?

The antigen-binding site is composed of the variable regions of the 2 heavy chains.

Which of the following is most involved in how the host range of a virus is determined?

the proteins on the surface of the virus and host cell

Which of the following descriptions about viral diseases is not correct?

The Spanish flu was caused by a type of coronavirus.

Which of the following is least likely a reason why new viral diseases appear in humans?

injection of viral particles into host species

Which of the following is not a function of reverse transcriptase after HIV enters its host cell?

RNA-dependent RNA polymerase

What is the main purpose of vaccination?

Vaccination generates memory immune cells that carry the 'memory' of the substance that was introduced via vaccination.

Which of following descriptions about bacterial CRISPR-Cas is not correct?

CRISPR is a nuclease that is targeted to the foreign DNA.

Which of the following most accurately describes why certain vaccinations can prevent cancer?

Because certain viral DNA integrates into the host cell DNA and acts as oncogenes.

Which of the following descriptions of the lysogenic cycle in phages is incorrect?

A large number of phages are released at a time.

HSV-1 is a type of herpes virus that typically causes blisters or sores on or around the mouth. Why do people who have been infected by this virus have blisters reoccur upon stress or fatigue even though they have previously been free of symptoms for prolonged periods?

Herpes virus leaves copies of the viral DNA as mini-chromosomes in the host nuclei and remain latent until certain signals trigger new virus production.

Which of the following descriptions about RNA viruses is not correct?

RNA viruses with a double-stranded RNA genome are more common than those with a single-stranded RNA genome.

virus

a ___ is a very small infectious particle consisting of nucleic acid enclosed in a protein coat and, in some cases, a membranous envelope.

single

DNA viruses contain either double- or ____-stranded DNA

RNA

RNA viruses contain either double - or single-stranded ___

capsid

the protein shell that encloses the viral genome.

capsomeres

capsids are built from protein subunits called ___

viral envelope

viral accessory structure that helps host cell infection. Surrounds the capsid of influenza viruses and many other viruses found in animals. Derived from membranes of host cells and contains a combination of vial and host cell molecules.

Bacteriophages (phages)

viruses that infect bacteria. Their capsids are most complex among known viruses. Contain elongated capsid head that encloses their DNA.

obligate intracellular parasites

viruses are ___, which means they can replicated only within a host cell

host range

each virus has a ___, a limited number of host cells that it can infect

lock and key

____ fit between proteins on the outside of the virus and specific receptor molecules on the host’s surface.

enzymes

virus makes use of host ___, ribosomes, tRNAs, amino acids, ATP, and other molecules, and manufactures viral proteins.

unique polymerases

____ are often synthesized or carried in viral capsid.

self-assemble

viral nucleic acid molecules and capsomeres spontaneously ____ into new viruses and exit the cell.

The Lytic Cycle

produces new phages and lyses (breaks open) the host’s cell wall, releasing the progeny viruses.

virulent phage

a phage that reproduces only by the lytic cycle

The Lysogenic Cycle

replicates the phage genome without destroying the host.

prophage

viral DNA is incorporated into the host cell’s chromosome. in the ___ stage, one of the viral genes codes for a protein that represses most other ___ genes.

toxins

some prophages are expressed during lysogeny, and some cause the host bacteria to secrete ___ that are harmful to humans (food poisoning diphtheria, botulism, scarlet fever)

daughter cells

every time the host divides, it copies the phage DNA and passes the copies to ____

lytic mode

an environmental signal can trigger the virus genome to exit the bacterial chromosome and switch to the ____

temperate phages

phages that use both the lytic and lysogenic cycles ex) lambda phage

natural selection

____ favors bacterial mutants with surface proteins that cannot be recognized as receptors by a particular type of phage

restriction enzymes

foreign DNA can be identified as such and cut up by cellular enzymes called ____

methylated

the bacterium’s own DNA is protected from the restriction enzymes by being ____

CRISPR-Cas system

both bacteria and archaea can protect themselves from viral infection with the ____

two key variables used to classify viruses that infect animals

DNA or RNA? single-stranded or double-stranded? presence or absence of membranous envelope?

membranous envelope

many viruses that infect animals have a ____

glycoproteins

viral ____ on the envelope bind to specific receptor molecules on the surface of a host cell.

Golgi apparatus

some viral envelopes are formed from the host cell membrane as the viral capsids exit, other viral membranes form from the host’s nuclear envelope and are then replaced by an envelope made from ____ membrane.

herpesvirus

double-stranded DNA virus. envelope is derived form nuclear envelope of host. replicate within cell nucleus, and in some cases, copies of the ____ DNA remain behind as mini-chromosomes in the nuclei of certain nerve cells.

mini-chromosomes

____ remain for life until triggered by physical or emotional stress to leave the genome and initiate active viral production.

reverse transcriptase

retroviruses copy their RNA genome into DNA using ____

AIDS (acquired immunodeficiency syndrome)

HIV (human immunodeficiency virus) is a retrovirus that causes ____

provirus

the viral DNA that is integrated into the host genome is called a ___. function both as mRNA for synthesis of viral proteins and as genomes for new virus particles released from the cell.

permanent resident

unlike a prophage, a provirus remains a ______of the host cell

cellular nucleic acid

since viruses can replicate only within cells, they probably evolved as bits of _____

plasmids and transposons

candidates for the source of viral genomes include ___

mobile genetic elements

plasmids, transposons, and viruses are all ___

hydrolytic enzymes

viruses may damage or kill cells by causing the release of ____ from lysosomes, or by producing toxins or molecular components such as envelope proteins that are toxic.

vaccines

____ are harmless variants or derivatives of a pathogen that stimulate the immune system to mount defenses against the harmful pathogen. they can prevent certain viral illnesses.

antibiotics

viral infections cannot be treated by _____. antiviral drugs can help to treat, not cure, viral infections by inhibiting synthesis of viral nucleic acids and by interfering with viral assembly.

pandeminc

a global epidemic is called a ___

epidemic

in 2014, widespread outbreak (___) of Ebola virus: causes hemorrhagic fever, and often fatal illness.

nine RNA segments

influenza viruses have ___ in their genome, leading to many new genetic combinations and also have a high rate of mutation.

Spanis flu

the ___ was a pandemic caused by a new form of influenza H1N1 virus with an avian origin.

possible causes of rapidly emerging viral diseases in humans

mutations of existing viruses into new ones that can spread more easily. the spread of a viral disease from a small, isolated human population, the spread of existing viruses form other animals.

icosahedral capsids

most plant viruses are RNA viruses with helical or ____

horizontal transmission

entering through damaged cell walls

vertical transmission

inheriting the virus from a parent

plasmodesmata

viruses can spread throughout plants via___

prions

are infectious proteins that appear to cause degenerative brain diseases in animals. incorrectly folded proteins, can be transmitted in food, act slowly, and are virtually indestructible.

misfolded version

prions can convert a normal form of a protein into the ____. several prions aggregate into a complex that can convert more proteins to prions, which join the chain.

anatomy

the study of the biological form of an organism

physiology

the study of the biological functions an organism performs.

convergent evolution

the process by which unrelated or distantly related organisms evolve similar body forms, coloration, organs, and adaptations.

surface area, volume

rate of exchange is proportional to a cell’s ____ while amount of exchange material is proportional to a cell’s _____

hydra

saclike body of two cell layers facilitates diffusion of materials

interstitial fluid

in animals, the space between cells is filled with ____, which links exchange surfaces to body cells