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1. Who is named the “Father of Genetics?”
Gregor Mendel
2. Why did he use pea plants? To study the inheritance of traits
What results when the offspring (F1) of true breeding parents self-pollinate (breed with themselves)?
Genotype Ratio: 1 PP: 2 Pp: 1 ppPhenotype Ratio: 3 Purple: 1 White
Pp Pp
Pp Pp
PP Pp
Pp pp
More times you flip a penny, the more likely you are to
get the “expected” outcome (probability).
½ heads, ½ tails
½ x ½ x ½ x ½ x ½ x ½
1/64
If you toss a coin 6 times in a row, what is the probability it will land heads for all 6 tosses?
Independent AssortmentDuring gamete formation, genes for different traits
separate without influencing the other.Foil each parentto get 4 gametes
G g Y y GYGygYgy
Complete Dominance
The dominant trait (G) over shadows the recessive trait (g) and only the dominant trait shows up in the phenotype.
Incomplete Dominance
Neither trait is dominant over the other and a new trait is displayed. BLENDING!!!Red flowers crossed with white flowers make pink flowers.
Co-Dominance
Both traits are equally displayed and neither is dominant over the other.ABO blood types: A blood x B blood = AB blood
Describe the genotypes and phenotypes of each blood type:
AB has same Genotype & Phenotype
Co-Dominance
What are polygenic traits?Traits that have a wide variety of color ranges such as eye colors, hair color, skin color and
height.
First determine how many different letters are there for each letter type
then multiply!
A A B b C c D d E E F F G g H h 1 x 2 x 2 x 2 x 1 x 1 x 2 x 2 =
32 gametes
How many different gametes?
Can this parent AaBBccDdeeFfGgHH have a child with the following genotype? Why or why not?
NO, because the parent would need to have a big E in their genotype in order for the child to have an E.
A A B b C c D d E E F F G g H h
Know what forms from the sex cells in females and males!
4 Sperm are produced
1 Egg and 3 polar bodies are produced
FemaleMale
The paired, Homologous Chromosomes
come together during Meiosis I to make Tetrads
The chromatids pull apart during Meiosis I I
4 genetically different cells result at the end of MeiosisHaploid = 1None set of chromosomes
Know the stages of Meiosis I & II
Mitosis Meiosis
Somatic Cells - all body cells except sex cells
Sex Cells – Gametes(Egg or Sperm)
2 genetically identical cells 4 genetically different cells
Diploid – “2N”2 sets of Chromosomes
Haploid – “N”1 set of Chromosomes
No Genetic Diversity GENETIC DIVERSITY!
Goes through PMAT once(Prophase, Meta, Ana, Telo)
Goes through PMAT twice(Prophase I, Meta I, Ana I, Telo I)
then(Prophase II, Meta II, Ana II, Telo II)
VS
Karyotype
Shows:• Autosomes = all chromosomes # 1 - 22 chromosome
pairs (not sex chromosomes)• Sex Chromosomes
XX= female or XY= male (# 23 pair)• Homologous Chromosomes = chromosomes that
code for the same traits and pair up with each other• Inherited Disorders (ex: Down’s, Turner’s,
Kleinfelter’s, Super males/females)
46 Chromosomes
23 Pairs
Non-disjunction –When chromosome pairs don’t separate properly during Meiosis I
Can involve all chromosomes (sex, autosomes
Fatherdetermines
sex of offspring
Father provides either an X or a
Y to pair up with the
mother’s X to make a boy or
girl50% chance of Boy XY 50% chance of Girl XX
Pedigree Chart •shows how a trait is passed from one generation to the next•Shows male or female•Shows “no trait” “carries trait” or “has trait”
3 Generations shown
Normal Male
Normal Female
Female with Trait
Carrier Female
Male with Trait
Line = Marriage
Know the term Sex-linked genes/traits and how the key and Punnett square would look. What chromosome carries these types of traits?
XB Xb
Xb XBXb XbXb
Y XBY XbY
XBXb x XbY female carrier x male color blind
Phenotypes: 1 Female/Carrier 1 Female/Color blind1 Male/Normal 1 Male/Color blind
Sex-linked traits only carried on X Y doesn’t carry traits
Sex-linked gene/trait – Traits linked to sex chromosomes such as hemophilia or colorblindness
Know how to do the following types of crosses:
•Monohybrid Cross (1 Trait; Complete Dominance)•Dihybrid Cross (2 traits)
•Incomplete Dominance Cross (Red, Pink, and White Flowers)
• Co-Dominance Cross (Blood Groups)
• Sex-linked Cross (XᴴX P & X PY)
(key, parents’ genotypes, possible gametes, Punnett square, genotypes and phenotypes of offspring)
•Allele- Different forms of a gene•Gametes- Sex Cells (egg & sperm – Haploid)•Gene- Part of a chromosome; codes for traits•Genetics- Study of how traits are passed generation to generation• Karyotype- Picture of all paired chromosomes
Autosomes and Sex Cells•Pedigree- Family tree (picture) shows passing of trait from one generation to the next generation•Probability - Chance of something happening•Punnett Square- Chart showing offspring’s trait probabilities
•Dominant – Gene whose effect masks the partner (recessive) trait•Recessive – Gene whose effect is masked by partner (dominant) trait•Genotype – Genetic makeup of organism (letters)•Phenotype – Trait expressed “physical” looks•Heterozygous – Pair of different alleles (Rr)•Homozygous – Pair of same kind of alleles (RR) (rr)
•Trait – Inherited characteristic (feature)•Homologous – Pair of same kind of chromosomes
•Co-dominance – Both alleles expressed EQUALLY•Incomplete dominance – Blending of traits•Diploid – Having 2 sets of chromosomes “2N”•Haploid – Having 1 set of chromosomes “N”•Independent Assortment – Genes that separate have no effect on the other’s inheritance•Non-disjunction – When chromosomes don’t separate•Segregation – Separation of alleles