ANSWER KEY FOR PROBLEM SET #1

1.Metaphase: 3; microtubules (spindle fibers) bind to the centromere; migration of the centromere to the equatorial plate; shortest stageTelophase: 5; cytokinesis (cytoplasmic division) occurs; nuclear envelopes being to reform; chromosomes elongateInterphase: 1; cell growth; replication of the DNA in each chromosome; longest stageProphase: 2; nuclear envelope disappears; chromatin condenses which causes the chromosomes to appear; spindle fibers formAnaphase: 4; sister chromatids separate and migrate to opposite poles in the cell; shortest stage

NOTE: Other characteristics may be acceptable

2.egg, 130, sperm, 23, 10-15 hours, 48-72 hours, upper 1/3 of the oviduct, zygote, fertilization, uterus, placenta

3.Amniocentesis: A procedure where a sample of amniotic fluid and cells is removed from a woman who has been pregnant for 14-18 weeks. The purpose of the test is to identify genetic, chromosomal, and biochemical abnormalities in a developing fetus.

Chorionic Villi Sampling (CVS): A procedure involving the collection of a sample of cells from the outer of the two birth membranes (the chorion) and analyzed for potential genetic and chromosomal defects in the embryo/fetus. The sample is obtained at 6-10 weeks after fertilization

Ultrasound: The fetus can be “seen” in the mother’s womb. This procedure is used to detect multiples, physical defects and the position of the developing fetus and placenta. The procedure has no specific time limitations.

Endoamnioscopy: A technique permitting direct visualization of the developing fetus. This procedure is used to detect abnormalities such as spina bifida and cleft lip. It has no specific time limitations.

4.diploid- A condition where each cell has two of each kind of chromosome; 2n=46. Body (somatic) cells are examples of cells that each contain a diploid number of chromosomes.

Haploid- A condition where each cell has only one of each kind of chromosome; n=23. An example of a haploid cell is an egg or sperm.

5.46 chromosomes x 2 chromatids per chromosome = 92 chromatids.

6.23 = 8 .

7.metacentric, submetacentric, acrocentric.

8.total length, centromere position, secondary constrictions and differential staining bands; S phase portion of Interphase.

9.DNA is the genetic material. DNA is a triplet code, has punctuation, is anon-overlapping code, and is redundant or degenerate.

10.bases, phosphate, deoxyribose.

11.Adenine - purine, Cytosine - pyrimidine, Thymine - pyrimidine, Guanine - purine, Uracil - pyrimidine

Thymine is found only in DNA; Uracil only in RNAA & T are bound by double hydrogen bonds.C & G are bound by triple hydrogen bonds.

12.Transcription, Translation.

13.messenger RNA - contains the coded information of a specific gene.transfer RNA- carries specific amino acids to the sites of protein synthesis as a result of the tRNA’s anticodons matching the codons of the mRNA.ribosomal RNA- located in the ribosomes. . .the sites of the protein synthesis.

14.DNA template: CTATCTACAGGTmRNA: GAUAGAUGUCCAamino acid sequence: Asp-Arg-Cys-Pro

15.A mutation is any transmissible change in the genetic material. Chromosomal mutations are microscopically visible changes in the chromosome number or structure; e.g. an extra chromosome #21. . .the cause of Down syndrome. A point mutation usually involves a single nucleotide (base) pair, e.g. a substitution of one base pair for another, a deletion or addition of a base pair.

ANSWER KEYS FOR TESTS #1

TEST #1 KEY FEBRUARY 5, 1999

1.a. Regulatory Protein - A class of proteins (gene products) involved in regulating various activities in the body, e.g., insulin helps to control blood sugar levels, testosterone . . . a hormone influences “masculinizing” traits, phenylalanine hydrolase catalyzes the conversion of phenylalanine to tyrosine.

b.Carey H. Bostian - Former NCSU Chancellor and geneticist. Created GN 301 40 years ago and contributed extensively to the development of “Genetics in Human Affairs” in the early years.

c.AID - Artificial Insemination by Donor. Using sperm from someone other than spouse/significant other to achieve fertilization and pregnancy. In so doing, sterility, risk of transferring a known undesirable gene, Rh incompatibility, etc. can be avoided.

d.S Phase - “Middle” part of Interphase where/ when DNA is replicated. S= Synthesis . . . of DNA. Chromosomes become double, i.e., with sister chromatids as a result of completing S.

e.t RNA - Transfer RNA. tRNA molecules carry specific amino needs to specific locations on the surface of ribosomes, bond momentarily to specific mRNA codons and transfer their amino acids to the growing chain of amino acids.

f.Thymine - One of the 4 DNA bases or nucleotides. A pyrimidine. Parts with Adenine double hydrogen bonds to it. Not found in RNA.

2a. A 2f. B2b. B 2g. A2c. D 2h. A2d. E 2i. B2e. A

3a. D3b. B3c. C3d. A

4a. F - haploid (or monoploid)4b. F - cytoplasm4c. T4d. F - oviducts (Fallopian Tubes) false part of statement4e. F- Thymine (or Deoxyribose)4f. T4g. F - the zygote (or embryo, or Blastocyst)4h. T4i. T4j. T4k. 1 ½ for T; ½ for F, 1 for correcting False part of statement

5.Diagram to be made for answers.

6a. Up to 4 points for each of two well communicated and documented responses.6b. Each must be reasonably well explained/elaborated. The two should be quite different from each other.

7.a. UGA

7b. STOPPunction, period, comma, etc . . . meaning no covering acid is add/inserted into the gene product/protein for the mRNA codon. Instead, this signals the end of the gene’s message . . .the translation of the code should STOP here.

7c. AUG, UGG7d. 50%, 50%

8a. 2003 (or 2004, or 2005)8b. 80,000 (60,000 - 100,000 = OK)8c. 3 Billion8d. NIH and DOE (or vice versa)8e. Either Good or Bad (zero points for “GOOD” or “BAD” Two points for quality of explanation/documentation of why it is “Good” or “Bad”.)

9.5 points on Class Attendance Record.

10.Signature

TEST #1 KEY May 26, 1999

1.a. Amniocentesis - Method for obtaining fetal cells at 14-18 weeks prenatal to analyze for any of > 100s of genetic and chromosomal problems, e.g., Down Syndrome in females > age 35, family history of cystic fibrosis, etc.

b.Polar Body - Small cell produced in Meiosis (sex cell formation) containing a haploid set of chromosomes. Contains little cytoplasm, this will not survive even if fertilized. Its production permits the other haploid daughter product (the egg) to have an enormous cytoplasm.

c.Genetic Engineering (Gene Therapy) - Procedure/technique for altering (changing) DNA for therapeutic reasons, e.g., supplying the DNA to a person with Sickle Cell Anemia to alleviate the health consequence.

d.AIH - Artificial Insemination by Husband. May be used to overcome a low sperm count, a physical or emotional problem preventing fertilization via sexual intercourse.

e.Human Genome Project - Mammoth effort to map and sequence all of the DNA in human’s 24 chromosomes (22 autosomes, X, Y). i.e. to determine the location of each of our ~ 80,000 genes and to identify the DNA stair step sequence of each.

f.Phenylketonuria (PKU) - Recessively inherited condition resulting from a block in the normal conversion of phenylalanine to tyrosine. Toxic to CNS. Prenatal screening to identify PKU individuals and to provide a diet low in phenylalanine spares them from mental retardation.

2a. F - two 2f. F - haploid (or monoploid)2b. T 2g. F - Fertilization2c. T 2h. F - anaphase2d. F - implantation2e. F - galactose (to glucose)

3a. B3b. C3c. D3d. A

4a. Sperm, Zygote, Blastocyst, Fetus, Newborn4b. Uracil, Codon, Gene, Chromosome, Umbilical Cord

5a. C 5e. A5b. D 5f. B5c. A 5g. B5d. E 5h. F

6.Up to 6 points for a well thought-out and elaborated response. 0 points for only YES/NO answers. All 6 points for their discussion, explanation . . .and the genetic sense it makes.

7.Up to 9 points total for two different well-discussed and explained reasons.

8a. D8b. PKU (or Phenylketonuria)8c. F

9a. UCA, Ser9b. UAG9c. UGG, AUG9d. 35

10. 5 points on Class Attendance Record

11.Signature

TEST #1 KEY FEBRUARY 14, 2000

1.a. STOP Codon - Any of 3 different 3-letter mRNA or DNA codons which signal the end of a gene’s message. No amino acid is added here. This always terminates the translation process.

b.G C - Three hydrogen bonds held/attract Guanine and cystosine to each other in DNA. One of the 4 base pairs/stair steps found in our genetic code.

c.Replication - Occurs in the S phase of the cell cycle. DNA is doubled, resulting in sister chromatids being formed, each with identical DNA molecules.

d.Sister Chromatids - The two longitudinal (left and right) identical halves of a replicated chromosome. Contain identical DNA.

e.Fetoscopy (Endoamnioscopy) - Procedure whereby structures in the body/fetus can be viewed. Utilizes a fiber optics light system to illuminate what one wants to observe. Can detect, e.g. spina bifida.

2a. 200,000,000 (100,000,000 - 300,000,000)2b. 50 (25-100)2c. 1) Acidic vagina

2) sperm “seen” as foreigners . . . attacked by female antibodies3) long distance to swim4) many male sperm are defective.5) sperm may try to fertilize any round object, not necessarily egg6) swim up the wrong Fallopian tube7) other reasons

3a. F - cytoplasm 3d. F - thymine (or uracil)3b. T 3e. T3c. F - protein 3f. F - Proteins are

4a. F - oviducts/Fallopian tubes4b. T4c. F - less4d. F - implantation4e. F - haploid (or monoploid)4f. T

5a. A 5e. D5b. A 5f. C5c. C 5g. B5d. C

6a.1)map all of our genes to specific chromosome, arm, band, etc.2)determine DNA stair step sequence for each gene . . . all of the DNA.

6b.2005 (possibly earlier, say, 2002-2003)

7a-7b. YES/NO is 1 point. 3 points for quality of reasoning . . . and explanation/elaboration. (Must include genetic perspective.)

8a. Albinism8b. F8c. D

9a. C9b. B9c. E9d. D

10a. rRNA, Ribosome, Cell, Tissue, Organ10b. DNA Base Pair, Codon, Gene, X chromosome, Chromosome #1

11a. CUA, Leu11b. AGU11c. 28

12.Signature

TEST #1 KEY SEPTEMBER 25, 2000

1.a. Sperm Cell - Haploid; n=23; gamete; capable of fertilizing egg; product of meiosis; little cytoplasm; motile/mobile; each one is unique genetically; 85,000 times smaller than egg.

b.Autosome - A non sex chromosome; #1 - #22; Not X or Y

c.Galactosemia - Due to a block in the conversion of galactose to glucose, galactose accumulates and is toxic to CNS development, the result: mental retardation. Inherited as an autosomal recessive (gg) gene. Dietary limitations of galactose eliminate the consequences.

d.U:A - Uracil double hydrogen bonds to adenine when given the opportunity, e.g., in mRNA/tRNA attraction in translation. Uracil is a pyrimidine, Adenine is a purine.

e.Carey H. Bostian - Former NC State Chancellor created GN 301; Dr. McKenzie’s mentor; Bostian Hall named for him, recently died.

f.Cousin Marriages - Increases the risk of children having genetic defects since all of us have (are carriers for) several “bad” genes, and some cousins share many genes (being 1/8 identical); the chance that a child would receive a double dose is increased.

2a. B 2d. C2b. D 2e. A2c. A

3a. 250,000,000 (+/- 100,000,000)3b. 50 (+/- 25)3c.

1)many sperm are defective2)hostile, acid uterine/vaginal environment3)attacked by antibodies4)swim up the “wrong” oviduct/Fallopian tube5)fertilize any round object6)it’s a long distance to swim7)others?

4a. C 4d. B4b. D 4e. E4c. B 4f. A

5a. No, no need for carrier testing, i.e. your “affected” child proved that both you and your mate are carriers . . . unless you have reason to suspect that the husband is not the father.

5b. Either YES or NO. Up to 3 points for why/why not. Be fairly generous here, but must make sense in a GN 301 context.

6a. E6b. PKU (Phenylketonuria)6c. C

7a.1)Map . . . to determine the specific chromosomal locations of each of our ~

80,000 genes.2)Sequence . . . to identify all of the DNA base pairs, their order, arrangement . .

for all 3+ billion stair steps.7b. ~ 2003 - 2005, although a rough draft is already finished (early 2000)7c.

1)human health/medical applications2)better understanding of our nature3)more accurate studies of evolutionary relationships

7d.1)genetic discrimination by insurance companies, employers, or governments.2)Money/cost3)Moral, religious, etc. objections, i.e. “playing God”

8a. Sperm, Zygote, Embryo, Fetus, Newborn8b. Ribose, mRNA Molecule, Chromosome #22, Chromosome # 2, Nucleus

9a. AUG, Met9b. AGU9c. UGG UAU (or UGG UAC)

9d. 31 %9e. No, 21 code words would be needed; 20 for 20 amino acids plus 1 for STOP. A doublet code would yield 4x4 = 16 code word . . . NOT enough to code for 21 things.

10a. F - and 10d. T10b. F - protein 10e. T10c. F - anaphase 10f. F - cytosine, three

11.Up to 5 points for Class Attendance Record.

12.Signature

TEST #1 KEY FEBRUARY 9, 2001

1.a. Human Genome Project - Mammoth effort to map and sequence all human genes/DNA, i.e. to identify the specific chromosomal location of each of the 75,000 genes +/- genes and to determine the stair step sequence of each. A rough draft is already completed.

b.Carey H. Bostian - Founder/creator of GN 301 . . . 40+ years ago; former NC State Chancellor, Bells in Bell Tower and Bostian Hall are both named for him, noted geneticist, Dr. McKenzie’s mentor.

c.Amniocentesis - Procedure used during 14 - 18 weeks of pregnancy to obtain fetal cells for a DNA genetic/chromosomal analysis. Hypodermic syringe/needle used to collect cells from amniotic cavity. Can identify, e.g. Down Syndrome and Cystic Fibrosis.

d.Diploid - 2n = 46. Chromosomal content of zygote and all cells that descend from it mitotically . . . thus we are diploid individuals; and a diploid species.

e.Anaphase - Stage of mitosis where chromosomes are being pulled by spindle fibers from the center of the cell toward the poles/sides of the cell.

f.Hypotonic Treatment - Used to swell cells and consequently spread out chromosomes so they can be seen easily/individually when examined under a microscope.

2a. F - 2n = 46 2f. T2b. F - uterus (or endometrium) 2g. T2c. F - preventing ovulation 2h. T2d. F - cytoplasm2e. F - telophase

3a. Sperm, Egg, Embryo, Fetus3b. Codon, Gene, Chromosome #11, Chromosome # 7

4a. D 4e. B4b. C 4f. D4c. B 4g. A4d. A

5a. A5b. B5c. C5d. A

6.a. YES or NO. Testing (DNA, gene, chromosomal) at some stage prior to implantation: e.g. egg or sperm. Zygote, at 8 cell stage, etc . . . OK, if they indicate testing of parents preconceptionally. NOT OK if they are testing by amniocentesis or CVS. Response must make sense in a GN 301 context.

b.Modifying genes/DNA of zygote (fertilized egg) . . . or up to 8 cell stage. YES or NO. Response must make sense in a GN 301 context.

7a-7b. Up to 4 points for each of two well documented “aspects” which clearly show they saw/experienced the “Miracle of Life” video.

8a. D8b. B8c. Albinism

9a. UCA, Ser9b. CAU9c. AUG UGG9d. 399e. No, a triplet code allows for 43 = 64 codons. A doubt code allows for 42 = 16

codons. 21 codons are needed: 20 for the amino acids and 1 for the STOP codon. Therefore, a doublet code would not have been sufficient.

10.Up to 5 points for Class Attendance Record.

11.Signature

TEST #1 KEY SEPTEMBER 24, 2001

1. a. Mapping and Sequencing - Goals of the Human Genome Project: to identify the location of each gene specific to chromosome and chromosome region (mapping), and to identify the DNA base pair/stair step ordering of all 3 billion steps (sequencing).

b. Placenta - Organ made by both fetus and mom through which nutrients, gases, wastes, etc. traffic to and from embryo/fetus from Mom. c. Chromosome #1 - Our biggest (longest) chromosome/autosome. Lots of important genes; metacentric. d. Blastocyst - The ball of cells post zygote -> to embryo stage. By 7-10 days after fertilization,the blastocyst will be approximately 27-10 (or approximately 100-1000) cells that implants in the uterine wall. After that, more specific tissues to organs begin to form, i.e. the embryo begins to develop. e. Amniocentesis - Means of testing the DNA, genes, chromosomes, biochemicals by 14-18 week fetus. Needle is inserted transabdominally in mom and 30+/- 10 cc of amniotic fluid and cells are removed. Ultrasound is used to guide the needle. f. Tyrosinemia - Very rare ailment due to a block in the degradation of tyrosine. Autosomal recessive, e.g., tt genotype, causes it. Joshua (Raleigh 4 year old) is the only living NC individual who has it!

2. a. F, interfering with sperm being deposited in vagina at intercourse. b. F, adenine c. F, phenylalanine to tyrosine d. F, oviducts (Fallopian tubes) e. F, metaphase f. T g. F, S (S Phase, replication) h. T

3. a. A b. E c. C d. D

4. a. E b. D c. A d. B e. B f. C (only half credit for A or B) g. F (only half credit for B or C) h. D

5. a.Sperm, Zygote, Embryo, Fetus b.Codon, Gene, Y Chromosome, Chromosome #11

6a-6b. Up to 4.5 points for each of two different aspects of the "Miracle of Life" video which clearlycommunicate having gained from watching it and remembering it.

7a-7b. Up to 4 points for a well thought out, well communicated response that makes GN 301 sense giventhe scenario. Either "Yes" or "No" is fine. It's the quality of the thinking behind it that can earn up to 4points.

8. a. albinism b. D c. F

9. a. AUG, Met b. AGU c. UGG UAU (or UGG UAC) d. 27

10. Up to 4 points for Class Attendance Record.

11. Signature, Student ID Number

TEST #1 KEY FEBRUARY 8, 2002

1. a. Carey H. Bostian - Former NC State Chancellor and Genetics Professor. Originated GN301 and taught it initially more than 4 decades ago. Bostian Hall is named after him. b. Genetic Discrimination - Concerns regarding the possible use of genetic test results to make decisions by employers, insurance companies, governments, and others on their employees or applicants, health/life insurance policy holders, tax benefits or deductions, etc. Federal and State laws are being enacted to prevent such. c. Fetoscopy or Endoamnioscopy - Procedure used to look at fetus and potentially detect developmental problems. Seldom used, except for research and photography educational purposes. d. PKU - Phenylketonuria. Due to a block in conversion of phenylalanine to tyrosine. Inherited as a recessive, i.e. it takes a pp (double dose of p) to not make the necessary P enzyme which catalyzes the conversion. Newborns are screened for it, and can prevent problems by dietary modifications. e. DNA, the Universal Language - All of life. . .from the simplest forms to humans have DNA as their genetic code. We all use the same chemical hereditary language, rules, and all. f. Autosome - Any of the non sex chromosomes, i.e. the numbered ones, 1-22.

2. a. F, keeping sperm from being deposited in vagina during sexual intercourse. b. F, tyrosine to melanin c. T d. T e. T f. F, adenine,two g. T h. T

3. a. B b. D c. A d. C

4. a. D b. F (half credit for B or C) c. C d. E e. D f. C (half credit for A or B) g. D h. A

5. a.Gene, Chromosome, Sperm, Egg b.Amino Acid, Enzyme, Ribosome, Cytoplasm

6a-6b. Up to 4.5 points for each of two different, reasonably well elaborated aspects that draw from the "Miracle of Life" video.

7a. Response needs to at least imply that "Preimplantation". . .loosely defined. . .as any time before theblastocyst/ball of cells reaches the uterus, e.g. could be testing of egg, sperm, zygote, one of the cells atapproximately the 8 cell stage, or even testing of potential parents before sexual intercourse leading toconception. 7b. Responses need to address testing for part a, therapy/genetic alteration for part b. Yes or No doesn't matter. What matters is that it makes GN301 sense and is reasonably well elaborated.

8.

a.6 b.4 c.PKU

9. a.CAU, His b.CAT, 3+2+2=7 c.AUG UGG d.18

10. 5 points for completing the survey.

11. Signature

TEST #1 KEY                              September 20, 2002

1.

a. AIH - Artificial Insemination by Husband. Used, e.g., when husband has low sperm count. By collecting semen from several ejaculations and inserting the combined collections into the vagina via artifical insemination. This way the couple may be able to overcome infertility.

b. Sister Chromatids - Sister chromatids are the two longitudinal identical halves of a replicated chromosome. They contain identical DNAs.

c. Spindle Fibers - During mitosis spindle fibers attach to each side of each chromosome's centromere and pull the chromosomes to the proper places. They enable chromosomes to move.

d. Diploid - 2n = 46. Diploid cells have chromosomes represented in pairs, e.g., two #1s, two #2s, etc. The zygote is diploid as are all the somatic cells that descend via mitosis from it.

e. Human Genome Project - The monumental NIH and DOE (federal) and private research effort to map and sequence all of the genetic information (DNA) in humans. . .all 3+ billion stairsteps, 30,000+ genes. As a consequence, the location of and spelling of all our DNA is now known and was completed in 2000.

f. Carey H. Bostian - Former NC State Chancellor. Originated GN 301 over 40 years ago. Bostian Hall and Bell Tower bells named for him. Dr. McKenzie's mentor.

2.a. Tb. F, uterus or endometriumc. Td. F, preventing sperm from reaching an egg

e. F, haploid or monoploidf. F, acrocentricg. F, metaphaseh. F, Deoxyribose to Ribose

3.a. Ab. Cc. Bd. E

4.a. F (half credit for B or C)b. Ac. C (half credit for A or B)d. Ae. Df. Ag. Eh. B

5.a. Sperm, Egg, Embryo, Fetusb. Codon, Gene, X Chromosome, Chromosome #1

6.a. 1. They have the same salt concentration.

2. Cilia that line the female reproductive tract are identical to those of single-cell organisms in the sea.

b. 1. Males produce low/slow amounts of regularly/uniformly. It's at a constant level.2. Females produce bursts of hormones cyclically/monthly.

c. 1. Adverse acidic environment of female reproductive tract.2. Attacked by white blood cells of female's immune system.3. Downward current which sperm must swim against.4. Many sperm are defective: two tails, etc.5. Some sperm fertilize other round objects/cells and don't make it to the egg.6. Some sperm swim up the wrong oviduct/Fallopian tube.

7.a. Db. Ec. PKU or Phenylketonuria

8.a. AGU, Ser

b. GUAc. AUG UGGd. 34%e. No. A doublet code (assuming the code uses the 4 bases A,G,C, and T) would

enable/generate 42 = 16 code words. 21 are needed; 20 for the 20 amino acids (one each) and 1 for punctuation (STOP). Such a system would not be sufficient

9. Up to 7 points for a well thought out, well supported statement reflecting a GN 301 perspective. Either YES or NO is fine. Grading/score is based on the quality of thinking (and communication of it) which supports the "answer".

10.a. Tb. F, Blue (or Gray)c. Td. Corrections e. Up to 2 points for a clear communication that indicates you actually saw and

learned from this exhibit.

11.Signature