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Which of the following is true about the harm done by teratogens? a. Passive smoking is rarely harmful to the developing fetus b. The genetic makeup of the mother and the developing organism plays an important role c. The negative impact of teratogens is usually reversible d. The most serious defects occurs in the period of the zygote

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Nestor Rutherford
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4 Feb 2019

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Related questions

1. Diseases are those abnormal conditionsin which the bodys defensive cells fail to make the self versus thenonself distinction correctly, and attack the body's owntissues.
A. Cancerous
B. Septic
C. Autoimmune
D. Nondiscrete

2. Which of the following determinesgenetic sex (male or female) in mammals?
A. the acrosome of the sperm
B. the temperature of the developing fetus
C. the SRY gene on the Y chromosome
D. the genetic makeup of the parents
E. the Y chromosome contained in the egg

3. Which of the following regardingantigens is true?
A. Antigens can only be recognized by their specificity.
B. An antigen is a molecule which promotes a general immuneresponse.
C. A large antigen is likely to have many different epitopes, eachof which can stimulate a distinct immune response.
D. The most effective antigen are small simple amino acidcomplexes.
E. Bacteria do not contain antigens.

4. All of the following are defensemechanism employed by vertebrates except

A. negative test, as in, not findingself-markers.

B. change in chromosomal composition

C. positive test to recognize presence ofnonself-markers

D. specific antibodies.

E. skin and mucous membranes asbarriers.

5. The immune system depends on thefunction of ______, which include several types of phagocytic cellsand two kinds of lymphocytes.

A. platelets

B. leukocytes

C. target cells

D. erythrocytes

6. In comparing the kidneys of marine andfreshwater fish, which of the following is not true?

A. Freshwater fish fluids have a greaterosmotic concentration.

B. Marine fish excrete many of the divalentcations through the anus.

C. The flow of the filtrate is faster inmarine fish.

D. The urine is less concentrated infreshwater fish.

E. Marine fish drink greater quantities ofwater.

7. The kidneys of which one of thefollowing are so highly efficient that it never has to drink waterand can obtain all of its water from its food?

A. desert lizard

B. camel

C. pocket moue Perognathus

D. kangaroo rat

E. gerbil

8. Select the incorrect statement regardingthe temperature of the immune system.

A. Interleukin-1 is a pyrogen, which cancause the neurons in the hypothalamus to raise the body'stemperature, producing a fever.

B. Fevers cause the liver and spleen tostore sodium and potassium which bacteria need for their growth andmetabolism.

C. Fevers above 105 ° F can be fatal.

D. Fever contributes to the body's defensesby stimulating phagocytosis.

E. When macrophages encounter invadingcells, they release interleukin-1, which is carried to the brain bythe circulatory system.

9. Which of the following is not amechanism to prevent polyspermy?

A. change in membrane otential of egg

B. vitelline envelopes lift off surface ofegg

C. sperm nuclei degraded inside eggallowing one to fuse

D. cortical granule enzymes remove spermreceptors from egg

E. altering composition of exterior eggcoat

10. Which of the following cells have anincorrect function?

A. neutrophil---important antigenpresenting cell

B. eosinophil---important to theelimination of parasites

C. mast cell---releases histamine

D. macrophage---phagocytic cell

E. monocyte---precursor of macrophage

11. Which part of the antibody moleculedetermines its role in the immune response?

A. disulfide chains

B. the entire molecule

C. the stem of the Y

D. the heavy chains

E. two arms of the Y

12. Select the incorrectly matchedimmunoglobin (Ig)subclass and a fact about it.

A. IgG---found in the plasma and secretedin secondary response

B. IgM---first secreted during primaryresponse

C. IgE----promotes the release ofhistamine

D. IgA----found in saliva and mother’smilk

E. IgD----serve as receptors on thesurfaces of T cells

13. _______ are the source ofantibody-producing cells.

A. B cells

B. Plasma cells

C. Monocytes

D. Macrophages

E. T cells

14. Select the incorrect statementregarding the inflammatory response.

A. The alarm signals can be histamines orprostaglandins.

B. The inflammation response is a localizedspecific response to infection or injury.

C. Neutrophils spill chemical in the areaof injury or infection that kills bacteria, tissues, andthemselves.

D. Tissue can exhibit edema from thedilation of the blood vessels in the area of injury orinfection.

E. If a cell is injured or infected, itreleases chemical alarm signals that promote dilation of bloodvessels at the injury site.

15. Reproduction in reptiles compares toreproduction in birds in that

A. both newly hatched birds and reptilesrequire parental care.

B. the eggs of both birds and reptiles haveprotective shells.

C. birds are oviparous, reptiles areovoviviparous.

D. both exhibit external fertilization.

E. male or female reptiles reproduceasexually; birds do not.

16. ______diseases are those abnormalconditions in which the body’s defensive cells fail to make theself versus the nonself distinction correctly, and attack thebody’s own tissues.

A. Cancerous

B. Septic

C. Autoimmune

D. Nondiscrete

17. Most marine invertebrates areosmoconformers. This means that

A. the osmolality of their body fluids isequal to that of the osmoregulators who inhabit the sameenvironments.

B. the osmolality of their body fluidsfluctuates between being hypertonic to hyportonic depending on theseason and the tides.

C. the osmolality of their body fluids isnot the same as their seawater environment

D. the osmolality of their body fluids isthe same as their seawater environment and that their bodiescontain the same solutes as their surroundings

E. the osmolality of their body fluids isthe same as their seawater environment

18. Which of the following determinesgenetic (male or female) in mammals?

A. the acrosome of the sperm

B. the temperature of the developingfetus

C. the SRY gene on the Y chromosome

D. the genetic makeup of the parents

E. the Y chromosome contained in theegg





If you can please explain why and how yougot the answer. 5 star rating for correct answers only, I have theanswer sheet, and just want to double check.

Expression vectors inprokaryotes do not make functional eukaryotic gene products inbacteria very well because

Answer Not sure which one ?!

· the codon sequence for prokaryotes is differentthan the codon sequence in eukaryotes

· there are no disulfide bridges formed in proteinsnormally made in prokaryotes

· prokaryotic expression vectors cannot translateeukarytic sequences

· eukaryotic genes have introns, and prokaryotesdon't

· eukaryotic genes have exons and prokaryotesdon't


I create a knockout mouseusing the agouti/black fur system \. When I cross the agoutioffspring of the originally engineered mouse, I find a ratio of 2agouti mice to 1 black furred mouse. What is the bestexplanation?

Answer not sure which one?!

· The gene knocked out was recessive.

· The gene knocked out was dominant.

· The gene knocked out was a lethalgene.

· The knockput was integrated into a random spot,and did not knockput the original gene.

A restriction enzyme cuts DNAand leaves the following end

xxCTGCA
xxG

Which of the following could be the sequence of the correspondingend of the other end of the cut DNA?

Answer

· xxG
xxCTGCA

· xxC
xxGTGCA

· xxCCGAT
xxG

· xxGGCTA
xxC


An SNP always occurs dueto

Answer

· a one base-pair change.

· a three base-pair change.

· a single restriction site change.

· a single amino acid change.

· None of these.


I PCR out a mutated gene in apatient with Lisenbee chorea (the inability to dance in acoordinated fashion) and I compare it to another patient with thatsame disease phenotype. One subject had a mutation on chromosome 4,and the other subject couldn't rock it because of a mutation onchromosome 5. This is an exampe of

Answer

· pleitropy

· locus heterogeneity

· allelic heterogeneity

· dominant negative mutation

· penetrance

In his experiments, Mendelnoted that when two traits are involved in a genetic cross, theyare inherited independently of each other. Though Mendel didn'tknow about chromosomes, this still holds true (mostly)because

Answer

· genes on the same chromosome are often mixedthrough meiotic crossover during the formation ofgametes.

· variant alleles of the same gene do not interferewith the phenotypic expression of the gentoype in different geneticloci.

· most higher organisms are diploid, making only twoalleles available for every genetic locus, and there is a 50/50chance of geting either allele from a single parent.

· expression of phenotypes can vary from thegenotypes because of encironmantal influences.

· chromosomes often recombine

Anticipation is caused by amutation that increases in expressivity over subsequentgenerations.

Answer

· True

· False

Question 44

I have a genotype that shouldproduce a specific phenotype, but some of the individuals with thegenotype do not demonstrate any evidence of the phenotype. I wouldconsider this an example of

Answer

· allelic heterogeneity.

· locus heterogeneity.

· penetrance.

· expressitivity.

· sheer luck.

Question

Which of the following doesnot occur during the PCR reactions?

Answer

· Changes in the reaction temperature by athermocycler

· Denaturation at high temperatures

· Synthesis of oligonucleotide primers

· Extension of primers by DNA polymerase

· Annealing of oligonucleotide primers

Question

DNA markers, or variantnon-coding regions of DNA, are DNA polymorphisms that are usefulfor genetic mapping.

Answer

· True

· False

A mosaic is an organismwith

Answer

· multiple genotypes within one organism

· multiple alleles within one genotype

· more than one color of fur

· transgenes added to the zygote beforedevelopement

· a wt phenotype but a mutated genotype

Question

Genotype causesphenotype.

Answer

· No, gentoype just influences phenotype.

· Yes, genotype is the DNA sequence that createsphenotype.

Question

A true genetic chimera can becreated by

Answer

· mutating a gene early on in the development of anorganism resulting in different alleles being present in theadult

· multiple fertilized eggs or zygotes fusing to formone embryo

· adding a transgene to the genome of an organismduring fetal development only

· adding cells of a different species to an adultorganism

· adding a transgene to the genome of an animal atany stage in development

Question

The ABO blood group can bestbe explained by the concept of _______.

Answer

· dominant traits

· recessive traits

· allelic heterogeneity

· locus heterogeneity

· vampirism

If a loss of functionmutation creates a dominant phenotype, it may be becauseof

Answer

· haploinsufficiency

· penetrance

· expressivity

· allelic heterogeneity

· locus heterogeneity

Please select the best matchfor each.

Answer

· PCR: Technique used to generatecopies of a DNA fragment

· Southern blot : Screeningprocedure used to assay DNA fragments

· RFLPs : DNA fragments generatedby restriction enzymes that vary in length betweenindividuals

· Northern blot : Screeningprocedure used to assay mRNA fragments

· Electrophoresis Movement ofmacromolecules in an electrical field

Answer

A.

Screening procedure used toassay DNA fragments

B.

Movement ofmacromolecules in an electrical field

C.

Screening procedure used toassay mRNA fragments

D.

DNA fragments generated byrestriction enzymes that vary in length betweenindividuals

E.

Technique used to generatecopies of a DNA fragment

A gene mutates, and theprotein produced has a novel way of interacting with the cell, andcreates a new phenotype because of this new functionality. This iscalled

Answer

· pleitropy

· locus heterogeneity

· allelic heterogeneity

· dominant negative mutation

· gain of function dominant mutation

Question 62

Mutations in the somaticchromosomes may be inherited by the next generation.

Answer

· True

· False


A degenerate PCR primer withmany variant sequences must be used to make multiple copies of agene

Answer

· if only the protein sequence of the gene productis known to construct the primers

· if the DNA you are using is cDNA to constructthe primers

· if the DNA you are using is genomic DNA to becopied

· if the DNA you are trying to copy iscDNA

· if the vector is prokaryotic and the transformedcell is eukarytotic

Question

Please select the best matchfor each term.

Answer

· Restriction enzyme


· PCR C

· Plasmid

· YAC A

· Dideoxynucleotide

Answer

A.

Endonuclease isolated frombacteria

B.

Eukaryotic cloningvector

C.

Method for amplification ofDNA sequences

D.

Small circular fragment ofDNA

E.

Molecule used in DNAsequencing

Question

A couple goes on MauryPovitch, and the results are in: you are not the father. But noother man impregnated the female (granted, unlikely for a MauryPovitch guest, but work with me here) and he must be the father.DNA analysis claims otherwise, though the child definitely wasmom's (poor thing). What may be going on here?

Answer

· the child is parthenogenic because the motheractually impregnated herself like a shark, and the child's DNA isall mom's

· the child had a mutation that changed the genethat is used to trace paternity

· the child is a mosaic because he is actually a setof twins fused early during fetal development, and therefore camefrom 2 eggs and 2 sperm

· the dad may have germ-line mosaicism, meaning thatthe genotype of his sperm is different from his somaticgenotype

· mitochondrial DNA only comes from mom, so there isno way to tell whobthe baby's father is




1.

__________ are fairly small organelles that provide a safe place within the cell to carry out certain biochemical reactions that generate harmful, highly reactive oxygen species. These chemicals are both generated and broken down in the same location.

Lysosomes
Endosomes
Peroxisomes

Nucleosomes

2.

Biologists cannot possibly study all living species. Instead, they try to understand cell behavior by studying a select subset of them. Which of the following characteristics are useful in an organism chosen for use as a model in laboratory studies?

rapid rate of reproduction
all of the above
ability to grow under controlled conditions

amenability to genetic manipulation

3.

By definition, prokaryotic cells do not possess __________.

ribosomes.
a nucleus.
membrane bilayers.

replication machinery.

4.

Cell biologists employ targeted fluorescent dyes or modified fluorescent proteins in both standard fluorescence microscopy and confocal microscopy to observe specific details in the cell. Even though fluorescence permits better visualization, the resolving power is essentially the same as that of a standard light microscope because the resolving power of a microscope is limited by the __________ of light.

intensity
absorption
wavelength

filtering

5.

Choose the phrase that best completes this sentence: Microtubules ____________ and are required to pull duplicated chromosomes to opposite poles of dividing cells.

generate contractile forces
can rapidly reorganize
are found in especially large numbers in muscle cells

are intermediate in thickness

6.

Despite the differences between eukaryotic and prokaryotic cells, prokaryotes have proteins that are distantly related to eukaryotic actin filaments and microtubules. What is likely to be the most ancient function of the cytoskeleton?

cell division
cell motility
vesicle transport

membrane support

7.

DNA and RNA are different types of nucleic acid polymer. Which of the following is true of DNA but not true of RNA?

It contains thymine.
It has 5'-to-3' directionality.
It is single-stranded.

It contains uracil.

8.

Double covalent bonds are both shorter and stronger than single covalent bonds, but they also limit the geometry of the molecule because they ____________________.

prevent additional bonds from being formed with the bonded atoms.
limit the rotation of the bonded atoms.
create a new arrangement of electron shells.

change the reactivity of the bonded atoms.

9.

Drosophila melanogaster is a/an __________. This type of animal is the most abundant of all animal species, making it an appropriate choice as an experimental model.

mammal
amphibian
bird

insect

10.

If the isotope 32S has 16 protons and 16 neutrons, how many protons, neutrons, and electrons will the isotope 35S have, respectively?

16, 19, 17
16, 19, 15
16, 19, 16

16, 20, 15

11.

Living systems are incredibly diverse in size, shape, environment, and behavior. It is estimated that there are between 10 million and 100 million different species. Despite this wide variety of organisms, it remains difficult to define what it means to say something is alive. Which of the following can be described as the smallest living unit?

cell
organelle
protein

DNA

12.

Macromolecules in the cell can often interact transiently as a result of noncovalent interactions. These weak interactions also produce stable, highly specific interactions between molecules. Which of the factors below is the most significant in determining whether the interaction will be transient or stable?

the concentration of each molecule
the size of each molecule
surface complementarity between molecules

the rate of synthesis

13.

Many of the mechanisms that cells use for maintenance and reproduction were first studied at the molecular level in bacteria. Which bacterial species had a central role in advancing the field of molecular biology?

E. coli
S. pombe
C. elegans

D. melanogaster

14.

Many types of cells have stores of lipids in their cytoplasm, usually seen as fat droplets. What is the lipid most commonly found in these droplets?

cholesterol
isoprene
triacylglycerol

palmitic acid

15.

Mitochondria contain their own genome, are able to duplicate, and actually divide on a different time line from the rest of the cell. Nevertheless, mitochondria cannot function for long when isolated from the cell because they are __________________.

anaerobes.
viruses.
parasites.

endosymbionts.

16.

Mitochondria perform cellular respiration, a process that uses oxygen, generates carbon dioxide, and produces chemical energy for the cell. Which answer below indicates a correct pairing of material “burned” and the form of energy produced during cellular respiration?

fat, protein
sugar, fat
sugar, ATP
fat, ADP

17.

Polar covalent bonds are formed when the electrons in the bond are not shared equally between the two nuclei. Which one of these molecules contains polar bonds?

propane
methane
molecular oxygen
water

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