1. AP Biology Test Return/Lab return/Study guide return Chapter 13-15
Next test December 6 
Study guide Corrections too

2. Chapter 13- Meiosis
Heredity- or inheritance transmission of traits from one generation to the next
Genes- coded information with traits, segments of DNA
Gametes- reproductive cells (sperm and egg)

3. Somatic cells- cells other than reproductive cells
Locus- a specific location on a chromosome
Asexual reproduction vs Sexual reproduction
Life cycle- generation to generation sequence of stages in reproductive history

4. Chromosomes 46 human chromosomes (somatic) 2n (2 sets) Karyotype
Autosomes vs sex chromosomes
Haploid (n) – cells with a single chromosome set

5. Fertilization- union of gametes (sperm and egg) zygote is formed
Zygote- fertilized egg, diploid because it contains 2 haploid sets from each parent
Meiosis- process to form gametes, reducing chromosome number by half

7. Meiosis Interphase Meiosis I Meiosis II
Separates homologous chromosomes
Meiosis II
Separates sister chromatids

8. Meiosis I Prophase I Metaphase I Anaphase I Telophase I, Cytokinesis
Crossing over occurs
Metaphase I
Homologous chromosome PAIRS line up at middle
Anaphase I
Duplicated homologous chromosomes separate
Telophase I, Cytokinesis
2 cells result

10. Meiosis II Prophase II Metaphase II Anaphase II
Homologous chromosomes (sister chromatids) line up at center
Anaphase II
Sister chromatids separate
Telophase II, Cytokinesis

12. Mendel and Gene Idea Chapter 14
Blending hypothesis- genetic material mixes in a manner which blends traits
Mendel- peas
Traits- characteristic inherited
True-breeding – plants self-pollinate to have same traits as parents
Hybridize- cross (or cross-pollinate)

13. P generation – parent
F1 = Offspring of P
F2 = offspring of F1

14. Genotype –
Phenotype –
Alleles- alternative forms of traits
Dominant-
Recessive-

15. AP Biology

16. Mendel’s laws Law of segregation- Law of independent assortment-
2 alleles for a heritable character separate during gamete production (end up in different gametes)
Law of independent assortment-
Each pair of alleles segregates independently during gamete formation.

17. Problem: Homozygous black rabbit mates with a homozygous white rabbit
Phenotypic ratio:
Genotypic ratio:

18. Problem: Carry out a cross for the F1 generation: Phenotypic ratio:
Genotypic ratio:

19. Problem:
A brown tall rabbit is mated with a white short rabbit. Brown and tall are dominant. Construct a punnett square

20. Problem:
Use F1 to determine the F2 generation

21. Laws of probability govern Mendelian inheritance
Probability of tossing heads with normal coin:
Probability of rolling a 3 with a 6 sided die:

22. Law of multiplication
Used to determine probability of two or more independent events.
Probability that 2 girls are born in a row to a family:
Probability that 6 girls are born in a row to a family:

23. Law of addition:
The probability of an event that can occur in two or more mutually exclusive ways
The probability of producing an F2 heterozygote:

24. Mendel genetics = simple genetics
Incomplete dominance – intermediate offspring
Codominance – both traits are shown

25. Many genes exist in populations in more than two allelic forms:
ABO blood groups:
IA, IB, i

26. Pleiotrophic- when genes affect more than one phenotypic characteristic
Polygenic inheritance- additive effects of two or more genes on a single phenotypic character.

27. Pedigrees

28. AP BIO
Finish Chapter 15
Lab Tuesday
Test Thursday

29. AP Biology Thomas Morgan Worked with Drosophila (fruit flies)
Discovered wild type – characteristic found in nature
Mutants were alternatives to the wild type
Fruit flies- carry eye color on X chromosome
White eyes – w
Red eyes – w+

30. Not All organisms are XX and XY

31. SRY gene on Y
SRY (sex-determining region of Y) gene was discovered in 1990.
Individuals with the SRY gene embryonic gonads develop into testes
Individuals without the SRY gene develop ovaries

32. Genes located on Sex Chromosomes
Sex-linked genes
On Y = Y-linked genes
On X = X-linked genes
Color blindness
Hemophilia
Duchenne muscular dystrophy

33. Problem: Mother heterozygous for color blindness
Father is not colorblind
Results:

34. Barr body
Females inherit 2 X chromosomes, only 1 X chromosome is active.
Barr body- during development 1 X chromosome per cell condenses into a compact Barr body.
Barr bodies are not expressed.

35. Linked genes
Linked genes – genes located near each other on the same chromosome and tend to be inherited together.

36. Crossing over Accounts for recombination of linked genes
Occurs in prophase I meiosis I
New combinations result in varied offspring

37. Alterations of chromosome number
Nondisjunction –
members of a pair of homologous chromosomes do not separate properly during meiosis I
Or sister chromatids fail to separate during meiosis II.
Trisomic, monosomic cells
Polyploid – organisms with more than two complete sets of chromosomes

38. Breakage of chromosome structure
Deletion – when a chromosomal fragment is lost
Duplication- occurs when a fragent becomes attached as an extra segment to a sister chromatid.
Inversion – When chromosome fragment reattaches to the original chromosome in the reverse direction
Translocation- fragment joins a non homologous chromosome