Meiosis & Genetics Meiosis & Genetics Unit Review GuideUnit Review Guide

20112011

YMartinezYMartinez

1. Chromosome:1. Chromosome:

MEIOSIS

1. Chromosome1. Chromosome

threadlike strands threadlike strands made of made of

DNADNA and and PROTEINPROTEIN

2. Homologous 2. Homologous Chromosome:Chromosome:

2. Homologous 2. Homologous ChromosomChromosom

e:e:

chromosomes that each chromosomes that each have a matching have a matching

chromosome; one was chromosome; one was from mom and other from mom and other

from dadfrom dad

3. Diploid:3. Diploid:

3. Diploid:3. Diploid:

a cell that contains both sets a cell that contains both sets of homologous chromosomes of homologous chromosomes

(2n)(2n)

4. Haploid:4. Haploid:

4. Haploid:4. Haploid:

a cell that contains only a a cell that contains only a single set of genes (n)single set of genes (n)

5. Gamete:5. Gamete:

5. Gamete:5. Gamete:Is a sex cell. An egg or sperm. Is a sex cell. An egg or sperm.

(n)(n)

6. Meiosis:6. Meiosis:

6. Meiosis:6. Meiosis:form of cell division form of cell division

that halves the that halves the number of number of

chromosomes when chromosomes when forming gametesforming gametes

7. Which cells undergo 7. Which cells undergo Meiosis?Meiosis?

7. Which cells undergo 7. Which cells undergo Meiosis?Meiosis?

gametesgametes

8. 8. Describe what is Describe what is occurring in the occurring in the diagram to the diagram to the

right. right.

8. 8. Describe what is Describe what is occurring in the occurring in the diagram to the diagram to the

right. right.

Segregation Segregation

AndAnd

RecombinationRecombination

9. 9. What is the What is the difference difference

between somatic between somatic cells and sex cells?cells and sex cells?

9. 9. What is the What is the difference difference

between somatic between somatic cells and sex cells?cells and sex cells?

Somatic cells—ALL cells Somatic cells—ALL cells except sex cells.except sex cells.

Sex Cells—sperm and egg.Sex Cells—sperm and egg.

10. Describe the process of 10. Describe the process of fertilization (include number of fertilization (include number of chromosomes and cell types chromosomes and cell types

involved).involved).

10. Describe the process of 10. Describe the process of fertilization (include number of fertilization (include number of chromosomes and cell types chromosomes and cell types

involved).involved).n + n = 2nn + n = 2n

oror

23 + 23 = 4623 + 23 = 46

11. Autosome:11. Autosome:

KARYOTYPES ad Sex Chromosomes

11. 11. AutosomeAutosome

chromosome chromosome that is not a sex that is not a sex

chromosomechromosome

12. How many total 12. How many total chromosomes are chromosomes are found in a human found in a human diploid body cell?diploid body cell?

12. How many total 12. How many total chromosomes are chromosomes are found in a human found in a human diploid body cell?diploid body cell?

2n=2n=4646

13. How many 13. How many chromosomes are chromosomes are found in a human found in a human

haploid cell?haploid cell?

13. How many 13. How many chromosomes are chromosomes are found in a human found in a human

haploid cell?haploid cell?

n=n=2323

14. How many sex 14. How many sex chromosomes are chromosomes are

found in human body found in human body

cells?cells?In gametes?In gametes?

15. How pairs of 15. How pairs of autosomes are found autosomes are found

in FEMALE in FEMALE body/somaticbody/somatic

cells?cells?What are the sex What are the sex

chromosomes?chromosomes?

15. How pairs of 15. How pairs of autosomes are found autosomes are found

in FEMALE in FEMALE body/somaticbody/somatic

cells?cells? 2222What are the sex What are the sex

chromosomes?chromosomes? XXXX

16. How pairs of 16. How pairs of autosomes are found autosomes are found in MALE body/somaticin MALE body/somatic

cells?cells?What are the sex What are the sex

chromosomes?chromosomes?

16. How pairs of 16. How pairs of autosomes are found autosomes are found in MALE body/somaticin MALE body/somatic

cells?cells? 2222What are the sex What are the sex chromosomes? chromosomes? XYXY

17. Which parent 17. Which parent determines the determines the

gender of their baby, gender of their baby, why?why?

17. Which parent 17. Which parent determines the determines the gender of their gender of their

baby, why?baby, why?

Father.Father.

His Sperm have an His Sperm have an X or Y X or Y

Chromosome.Chromosome.

18. The diagram below 18. The diagram below is called a is called a

18. The diagram below 18. The diagram below is called a is called a

KaryotypeKaryotype

19. Draw a circle around 19. Draw a circle around the the sex sex

chromosomeschromosomes in the in the diagram above.diagram above.

19. Draw a circle around 19. Draw a circle around the the sex sex

chromosomeschromosomes in the in the diagram above.diagram above.

20. Draw 20. Draw squaressquares around the around the

autosomes in the autosomes in the diagram.diagram.

20. Draw 20. Draw squaressquares around the around the

autosomes in the autosomes in the diagram.diagram.

21. Is the diagram from 21. Is the diagram from a male or a female?a male or a female?

21. Is the diagram from 21. Is the diagram from a male or a female?a male or a female?

GUYGUY=X=XYY

22. What is another 22. What is another name for Trisomy 21 name for Trisomy 21 in a karyotype? What in a karyotype? What

causes it?causes it?

22. What is another 22. What is another name for Trisomy 21 name for Trisomy 21 in a karyotype? What in a karyotype? What

causes it?causes it?Down’s Down’s Syndrome Syndrome Caused byCaused by

Nondisjunction:Nondisjunction: when homologous when homologous chromosomes fail chromosomes fail to separate during to separate during

meiosismeiosis

23. Genetics: 23. Genetics:

Mendelian Genetics

23. Genetics: 23. Genetics:

scientific study of heredityscientific study of heredity

24. Heredity: 24. Heredity:

24. Heredity: 24. Heredity:

Is the passing of traits to Is the passing of traits to offspringoffspring

25. Gene: 25. Gene:

Mendelian Genetics

25. Gene: 25. Gene:

Segments of DNA that code Segments of DNA that code for a protein and determine a for a protein and determine a

traittrait

26. Allele: 26. Allele:

26. Allele: 26. Allele:

a different form of a genea different form of a gene

27. Genotype: 27. Genotype:

27. Genotype: 27. Genotype:

Genetic makeup of an Genetic makeup of an individualindividual

28. Homozygous: 28. Homozygous:

28. Homozygous: 28. Homozygous:

an organism that has two an organism that has two identical alleles for a identical alleles for a

particular traitparticular trait

Ex RR or rrEx RR or rr

29. Dominant: 29. Dominant:

29. Dominant: 29. Dominant: An allele for a particular form of a An allele for a particular form of a trait will always exhibit that form trait will always exhibit that form

of the trait.of the trait.

ex RR or Rrex RR or Rr

30. Hybrid: 30. Hybrid:

30. Hybrid: 30. Hybrid:

offspring of crosses between offspring of crosses between parents with different traitsparents with different traits

Ex RrEx Rr

31. Phenotype: 31. Phenotype:

31. Phenotype: 31. Phenotype:

Physical characteristic of an Physical characteristic of an individualindividual

32. Heterozygous: 32. Heterozygous:

32. Heterozygous: 32. Heterozygous:

an organism that has two an organism that has two different alleles for the same different alleles for the same

traittrait

Ex RrEx Rr

33. Recessive: 33. Recessive:

33. Recessive: 33. Recessive:

An allele for a particular form of a An allele for a particular form of a trait will exhibit that form only trait will exhibit that form only

when the dominant allele for the when the dominant allele for the trait is not present. trait is not present.

ex rrex rr

34. Pure-breed: 34. Pure-breed:

34. Pure-breed: 34. Pure-breed: term used to describe organisms term used to describe organisms that produce offspring identical to that produce offspring identical to

themselvesthemselvesEx RR or rrEx RR or rr

35. Sex-linked 35. Sex-linked

35. Sex-linked: 35. Sex-linked:

Genes on the X and Y Genes on the X and Y chromosomeschromosomes

36. If curly hair is dominant over straight hair.36. If curly hair is dominant over straight hair. DrawDraw a Punnett Square showing a cross a Punnett Square showing a cross between a homozygous dominant father between a homozygous dominant father

and a heterozygous mother. and a heterozygous mother. DescribeDescribe the the genotypes and phenotypes of the genotypes and phenotypes of the

offspring, including the percentages of offspring, including the percentages of each.each.

36. If curly hair is dominant over straight hair.36. If curly hair is dominant over straight hair. DrawDraw a Punnett Square showing a cross between a Punnett Square showing a cross between

a homozygous dominant father and a a homozygous dominant father and a heterozygous mother. heterozygous mother. DescribeDescribe the genotypes the genotypes and phenotypes of the offspring, including the and phenotypes of the offspring, including the

percentages of each.percentages of each.

CC x CcCC x CcGenotypes: CC and CcGenotypes: CC and Cc

Phenotypes:Phenotypes: CC, CurlyCC, Curly

and Cc, Curlyand Cc, Curly

CC Cc

CC Cc

C c

C

C

37. A plant has a genotype of 37. A plant has a genotype of TtPp, list all possible TtPp, list all possible genetic combinations genetic combinations found in the gametes found in the gametes

produced:produced:

37. A plant has a genotype of 37. A plant has a genotype of TtPp, list all possible TtPp, list all possible genetic combinations genetic combinations found in the gametes found in the gametes

produced:produced:

TPTPTpTptPtPtptp

38. What is the probability 38. What is the probability that a couple will have a that a couple will have a

female child?female child?A male child?A male child?

Why?Why?

38. What is the 38. What is the probability that a couple probability that a couple will have a will have a female child? female child? 1/2 or 50%1/2 or 50%A male child?A male child? 1/2 or 50%1/2 or 50%

Why?Why?

--All human egg cells carry a single X chromosome.

-Half of all sperm cells Half of all sperm cells carry an X chromosome carry an X chromosome and half carry a Y and half carry a Y chromosome.chromosome.

39. Describe the genetic 39. Describe the genetic reason that explains why reason that explains why colorblindness would be colorblindness would be found more commonly in found more commonly in males than in females?males than in females?

39. Describe the genetic 39. Describe the genetic reason that explains why reason that explains why colorblindness would be colorblindness would be found more commonly in found more commonly in males than in females?males than in females?

Since males have just one X Since males have just one X chromosome, all X-linked chromosome, all X-linked

alleles are expressed in males. alleles are expressed in males. Girls need 2 copies.Girls need 2 copies.

40. Use your knowledge 40. Use your knowledge of genetics and of genetics and colorblindness colorblindness

to describe the results to describe the results of the Punnett Square of the Punnett Square

below.below.

XC XC

X X XC X XC

Y XC Y XC Y

40. Use your knowledge 40. Use your knowledge of genetics and of genetics and colorblindness colorblindness

to describe the results to describe the results of the Punnett Square of the Punnett Square

below.below.

-All daughters are -All daughters are carriers carriers

(heterozygous)(heterozygous)

-All sons are -All sons are colorblindcolorblind

XC XC

X X XC X XC

Y XC Y XC Y

41. Describe 41. Describe incomplete incomplete dominancedominance. Give an . Give an

example.example.

41. Describe 41. Describe incomplete incomplete dominancedominance and and co-dominanceco-dominance. .

Give an example.Give an example.

Incomplete Dominance: Incomplete Dominance: Where one allele is not Where one allele is not completely dominant over completely dominant over another. another. The The heterozygous phenotype heterozygous phenotype is somewhere in between is somewhere in between the two homozygous the two homozygous phenotypes.phenotypes.

42. Describe 42. Describe co-dominanceco-dominance. Give . Give an example.an example.

42. Describe 42. Describe co-dominanceco-dominance. Give . Give an example.an example.

Co-dominance:Co-dominance:Both dominant and Both dominant and recessive allele recessive allele contribute to the contribute to the phenotypephenotype

ex Roan color in horses ex Roan color in horses has a gene for red and has a gene for red and white color--there are white color--there are equal numbers of both equal numbers of both colors evenly dispersed colors evenly dispersed within the coatwithin the coat

43. Law of 43. Law of Segregation: Segregation:

43. Law of 43. Law of Segregation:Segregation:

During gamete During gamete formation, alleles formation, alleles

segregate from each segregate from each other so that each other so that each

gamete carries only gamete carries only a single copy of each a single copy of each

gene.gene.

44. Law of Independent 44. Law of Independent Assortment:Assortment:

44. Law of Independent 44. Law of Independent Assortment:Assortment:

allele pairs separate allele pairs separate independently during the independently during the

formation of gametes, so they formation of gametes, so they have no effect on the inheritance have no effect on the inheritance

of each other.of each other.

45. Autosomal dominant 45. Autosomal dominant disorder: disorder:

(who will get it?)(who will get it?)

45. Autosomal dominant 45. Autosomal dominant disorder: disorder:

(who will get it?)(who will get it?)If you have one (Rr) or two dominant (RR) alleles If you have one (Rr) or two dominant (RR) alleles

for a genetic disorder, it will be expressed. for a genetic disorder, it will be expressed.

ex Achondroplasia, Huntington's disease (nervous ex Achondroplasia, Huntington's disease (nervous system disorder), Marfan Syndromesystem disorder), Marfan Syndrome

46. Autosomal recessive 46. Autosomal recessive disorder: disorder:

(who will get it?)(who will get it?)

46. Autosomal recessive 46. Autosomal recessive disorder: disorder:

(who will get it?)(who will get it?)If you have two recessive, rr, alleles for a If you have two recessive, rr, alleles for a

genetic disorder, it will be expressed.genetic disorder, it will be expressed.

ex PKU, Tay-Sachsex PKU, Tay-Sachs

47. What is genetic 47. What is genetic engineering?engineering?

Genetic Engineering

47. What is genetic 47. What is genetic engineering?engineering?

process of making changes in process of making changes in the DNA code of living the DNA code of living

organismsorganisms

48. A strand of DNA formed by 48. A strand of DNA formed by the splicing of DNA from two the splicing of DNA from two different species is called?different species is called?

48. A strand of 48. A strand of DNA formed DNA formed

by the by the splicing of splicing of DNA from DNA from

two different two different species is species is

called?called?

Recombinant DNARecombinant DNA

49. What is a restriction 49. What is a restriction enzyme?enzyme?

49. What is a restriction 49. What is a restriction enzyme?enzyme?

enzyme that enzyme that cuts DNA at a cuts DNA at a

specific specific sequence of sequence of nucleotidesnucleotides

50. If you were to inject 50. If you were to inject genetically engineered genetically engineered

DNA into an animal, into DNA into an animal, into which cells would you which cells would you

inject the DNA (inject the DNA (genesgenes) for ) for the best results?the best results?

50. If you were to inject 50. If you were to inject genetically engineered genetically engineered

DNA into an animal, into DNA into an animal, into which cells would you which cells would you

inject the DNA (inject the DNA (genesgenes) for ) for the best results?the best results?

Fertilized eggsFertilized eggs