GENETICS VOCABULARY WITH K.I.M.

1. GENETICS VOCABULARY WITH K.I.M. Common pea plant, Pisumsativum.

2. MENDELIAN GENETICS • Mendel’s experiments that were used to create two laws (law of segregation and law of independent assortment) still used to describe basic genetic inheritance today. • Law of segregation: For any particular trait, the pair of alleles of each parent separate and only one allele passes from each parent to an offspring. • Law of independent assortment: Alleles for different traits will be passed on from each parent independently of each other, which could result in completely new combinations of traits than seen in parents.

3. heredity • The passing of traits from parents to offspring.

4. trait • The different forms of a characteristic. • Examples: • Characteristic: Seed Shape • Trait: Round or Wrinkled

5. GENETICS • The study of heredity!

6. phenotype • An organism’s appearance. • Example: purple flowers, white flowers, yellow seeds, green seeds

7. genotype • The entire genetic makeup of an organism. Also, the combination of genes for one or more specific traits. • Example: PP or pp or Pp

8. heterozygous • One dominant and one recessive allele. • Example: Pp

9. HOMOZYGOUS • Two dominant or two recessive alleles. • Example: PP or pp

10. monohybrid • The offspring of two individual that differ in respect of a single gene. Crossing only one trait! • Memory Clue: Mono = one • Sentence: I created a monohybrid cross in order to calculate the probability of the pea plant having wrinkled or round seeds.

11. dihybrid • The offspring of two individuals that differ in respect to two traits. • Crossing two traits. • Memory Clue: di = two • Sentence: A dihybrid cross is used to test for dominant and recessive genes, which has a variety of uses in Mendelian genetics.

13. karyotype • An organized profile of a persons chromosomes. Chromosomes are arranged and numbered by size, from largest to smallest. • Chromosomes are isolated, stained and examined under the microscope. • Most often, this is done using the chromosomes in the white blood cells. • Picture of the chromosomes is taken through the microscope. • Then, the picture is cut up and rearranged by the chromosome’s size and lined up from largest to smallest. • There are 22 pairs of chromosomes (autosomes) • 23 pair are the sex chromosomes; used to determine an individual’s gender. • Females have two X chromosomes; males have an X and a Y chromosome. • Sentence: Trained cytogeneticists use karyotypes to look for missing or extra pieces of chromosome.

15. PUNNETT SQUARE • Used to organize all the possible combinations of offspring from particular parents.

16. probability • The likelihood that a possible future event will occur in any given instance of the event.

17. Dominant allele • The trait observed in the first generation when parents that have different traits are bred.

18. RECESSIVE ALLELE • A trait that is apparent only when two recessive alleles for the same characteristic are inherited. • Recede means “to go away” or “back off”

19. Co-dominance • The “dominant” and “recessive” traits appear together in the phenotype of hybrid organisms. • “Co” = “together” • Example: Roan fur in cattle Cattle can be red (RR = all red hairs), white (WW = all w hite hairs), or roan (RW = red and white hairs together). • Another example: Human blood type AB, in which two types of protein (“A” & “B”) appear together on the surface of blood cells.

20. Link to pics of roan • http://homepage.usask.ca/~schmutz/CowPatterns.html

21. Incomplete dominance • One trait does not completely dominant over another. These traits do not blend together, but each allele has its own degree of influence. • Example: Snapdragon flower • True breeding red crossed with true breeding white results in pink flowers!

22. SNAPDRAGONS!