Download So you say you want extra credit…

So you say you want extra credit…..
For points you will need to write, and write, and write some more! Each time you write the following definitions
you will receive 4 bonus points. Do it twice and you get 4 bonus points. All copies must be turned in by the 7:15
AM tardy bell on December 20th, 2016.
Rules:
1. You must hand write each copy.
2. One copy of #1 – 40 should be stapled together for submission. Do not finish
one copy half way down a page and start another on that same page.
3. No working on it in any class until all other assignments are completed.
4. All assignments for the nine weeks must be turned in for the bonus points to count.
5. How many copies can you do:
Enough to raise your grade one letter grade: Ex. 74% to an 84%
Be sure and write the entire definition!
1. Allele — alternative forms of a gene for each variation of a trait of an organism
co-dominant alleles-Two different alleles at a locus are responsible for different phenotypes, and
both alleles affect the phenotype of the heterozygote. For example, consider the situation where
there are three alleles A,B, and O that determine human blood type.
 autosomal- A locus on any chromosome but a sex chromosome. Not sex-linked. Three possible
genotypes are AA, BB, OO that correspond to the phenotypes of blood type A, B, and O
respectively;
2. complete linkage - Complete linkage describes the inheritance patterns for 2 genes on the same
chromosome when the observed frequency for crossover between the loci is zero.
3. Crossing over — exchange of genetic material between non-sister chromatids from homologous
chromosome during prophase I of meiosis; results in new allele combinations
4. Diploid — cell with two of each kind of chromosome; is said to contain a diploid, or 2n, number
of chromosomes
5. Dominant — observed trait of an organism that mask the recessive form of a trait
6. Egg — haploid female sex cell produced by meiosis
7. Fertilization — fusion of male and female gametes
8. Gamete — male and female sex cells, sperm and eggs
9. Genetic recombination — major source of genetic variation among organisms caused by reassortment or crossing over during meiosis
10. Genetics — branch of biology that studies heredity
11. Genotype — combination of genes in an organism
12. Haploid — cell with one of each kind of chromosome; is said to contain a haploid or n, number
of chromosomes.
13. Heredity — passing on of characteristics from parents to offspring
14. Heterozygous — when there are two different alleles for a trait
15. Homologous chromosome — paired chromosomes with genes fro the same traits arranged in
the same order.
16.Homozygous — when there are two identical alleles for a trait
17.Hybrid — offspring formed by parents having different forms of a specific trait.
18. Law of independent assortment — Mendelian principal stating that genes for different traits
are inherited independently of each other.

19. Law of segregation — Mendelian principal explaining that because each plant has two different
alleles, it can produce two different types of gametes. During fertilization, male and female gametes
randomly pair to produce four combinations of alleles
20. Meiosis — type of cell division where one body cell produces for gametes, each containing half
the number of chromosomes in a parent’s body.
21. Nondisjunction — failure of homologous chromosomes to separate properly during meiosis;
results in gametes with too many or too few chromosomes
22. Phenotype — outward appearance of an organism, regardless of its genes.
23. Pollination — transfer of male pollen grains to the pistil of a flower
24. Recessive — trait of an organism that can be masked by the dominant form of a trait
25. Sexual reproduction- pattern of reproduction that involves the production of subsequent fusion
of haploid cells.
26. Sperm — haploid male sex cells produced by meiosis
27. Trait — characteristic that is inherited; can be either dominant or recessive
28. Zygote — diploid cell formed when a sperm fertilizes an egg.
29. hemizygous - If there is only one copy of a gene for a particular trait In a diploid organism, the
organism is hemizygous for the trait, and will display a recessive phenotype. X-linked genes in fly or
human males are hemizygous.
30. F1 generation - Offspring of a cross between true breeding plants, homozygous for the trait of
interest.
31. F2 generation - Offspring of a cross involving the F1 generation.
32. genotype- The genetic constitution of an organism with respect to a trait. For a single trait on an
autosome, an individual can be homozygous for the dominant trait, heterozygous, or homozygous for the
recessive trait. Yellow seeds are dominant, but yellow seeded plants could have a genotype of either YY
or Yy.
33. incomplete dominance - Intermediate phenotype in F1, parental phenotypes reappear in F2. The
flowers of the snapdragon plant can be red, pink, or white. Color is determined at a single locus. The
genotype RR results in red flowers and rr results in white flowers. The heterozygote genotype of Rr
results in pink flowers. When the heterozygote has a different, intermediate phenotype compared to the
homozygous dominant or homozygous recessive individuals, this is said to be incomplete dominance.
34. lethal alleles -Mutated genes that are capable of causing death.
35. true-breeding - Homozygous for the true-breeding trait.
36. linkage - genes that are inherited together on the same chromosome. Three inheritance patterns are
possible: non-linkage, Partial linkage, and complete linkage.
37. monoecious- Organisms produce both male and female gametes; i.e. garden pea.
38. monohybrid cross - Cross involving parents differing in only one trait.
39. mutation - Change in the DNA sequence of a gene to some new, heritable form. Generally, but now
always a recessive allele.
40. phenotype - The physical appearance of an organism with respect to a trait, i.e. yellow (Y) or green
(y) seeds in garden peas. The dominant trait is normally represented with a capital letter, and the recessive
trait with the same lower case letter.