CH 17: Part 1

AaLl x aall

1 Agouti (A), Long (L): 1 Agouti (A), short (l): 1 black (a), Long (L): 1 black (a), short (l)

PHENOtypic Ratio

tells the APPEARANCE of each class 3purple : 1white

Law of Independent Assortment

the INHERITANCE OF 1 TRAIT is INDEPENDENT OF the INHERITANCE OF ANOTHER trait ASSUME the GENES are NOT LINKED

Multiple Alleles

the trait is controlled by 1 GENE that has MORE THAN 2 FORMS

ABO Blood types have Multiple Alleles

there is 1 gene with 3 possible alleles -Type A: I^A allele -Type B: I^B allele -Type O: i allele Codominance with Multiple Alleles: can get EXPRESSION OF BOTH ALLELES, not blending

Laura (blood type A) has a child with blood type B and another child with blood type O. Who could have been the father of both of her children?

Laura. (type A): either I^AI^A or I^A i → IA ___ Child type B: I^BI^B or I^Bi, must receive I^B from dad Child type O: ii must receive i allele from mom & from dad Dad must be I^Bi (type B)

Mendel's Theory of Inheritance

Mendel was an Austrian monk in the 1860's he studied inheritance patterns of SIMPLE TRAITS = GENES in the garden pea these traits had easily distinguishable TYPES/ALLELES VISIBLE TYPE of a trait = PHENOTYPE

A person with blood type O has __________ Antigens on RBC

NO so they have ANTI-A & ANTI-B ANTIBODIES

Blood Type O

NO FUNCTIONAL ALLELES (i): -ii

Rh- Allele

NO Rh Antigen on red blood cells Genotype: Rh-Rh- ANTI-RH ANTIBODIES on blood serum

AntiBODY

PROTEIN in blood serum PRODUCED AGAINST the antiGEN of OPPOSITE BLOOD TYPE you DO NOT produce antibodies against your own antigens

What kind of GAMETES can the Red flowered plant (Rr = Red) produce?

R & r

Rh+ Allele

RH ANTIGEN on red blood cells Genotypes: Rh+Rh+ or Rh+Rh- NO ANTIBODIES in blood serum

The following cross was made: RR X rr What is the Phenotypic ratio of the offspring?

all Red (all Rr)

i Allele

codes for a NONfunctional ENZYME

I^A allele

codes for a functional ENZYME A Enzyme A (I^A allele) adds the A ANTIGEN to the RBC

I^B allele

codes for a functional ENZYME B Enzyme B (I^B allele) adds the B ANTIGEN to the RBC

Monohybrid Cross

study the inheritance of ONE TRAIT use TRUE-BREEDING = HOMOZYGOUS PARENTS for cross -PP = purple true-breeding -pp = white true-breeding -PP x pp = all Pp let the F1 plants self-pollinate: Pp x Pp -F2 generation: 3 purple & 1 white -Pp x Pp = 1/4PP + 2/4Pp + 1/4pp

In carnations R = Red & r = white. Heterozygotes are pink (Rr). A Red (RR) flowering plant is crossed with a pink (Rr) flowering plant. What is the Phenotypic ratio of the offspring?

1Red (RR): 1pink (Rr)

Dihybrid Cross Phenotypic Ratio for F2 generation when Alleles assort independently

9: 3: 3: 1 9 will be DOMINANT for BOTH trait 3 will be DOMINANT for 1 trait 3 will be DOMINANT for the OTHER trait 1 will be RECCESSIVE

A person with blood type A has the __________ Antigen on RBC

A so they have ANTI-B ANTIBODIES

A person with blood type AB has __________ Antigens on RBC

A & B so they have NO ANTIBODIES

A person with blood type B has the __________ Antigen on RBC

B so they have ANTI-A ANTIBODIES

Type AB+ Blood

Antigens on RBC: A, B, Rh+ possible Genotypes: I^AI^B Rh+Rh+ or I^AI^B Rh+Rh- What blood types can he receive? -ALL blood types = universal RECEIVER

Type O- Blood

Antigens on RBC: none = universal DONOR possible Genotypes: ii & Rh-Rh- What blood types can he receive? -ONLY O-

Codominance in Roan Cattle

C^wC^w = white C^RC^R = Red C^RC^w = Roan C^wC^w X C^RC^R → all C^RC^w (Roan)

Each Trait is controlled by 2 Alleles

DOMINANT allele: can mask the expression of the recessive allele need ONLY 1 DOMINANT ALLELE to see the DOMINANT PHENOTYPE Alleles for a Gene occur at the same GENE LOCUS = POSITION ON HOMOLOGOUS CHROMOSOMES HOMOzygous: organism has 2 of the SAME alleles HETEROzygous: organism has 2 DIFFERENT alleles

In fruit flies, Tan body-color (E) is Dominant over ebony (e). Suppose a cross between flies produced 120 Tan and 117 ebony F1 flies. The genotypes of the parents are:

Ee x ee Phenotypic ratio = 1tan : 1ebony the only cross that will give this ratio is Ee x ee

GENOtype

GENETIC COMPOSITION of an organism

AA x Aa or Aa x AA

GENOtypic ratio: 1AA : 1Aa PHENOtypic ratio: all Dominant

*Aa x Aa

GENOtypic ratio: 1AA : 2Aa : 1aa PHENOtypic ratio: 3 Dominant : 1 Recessive

*Aa x aa or aa x Aa

GENOtypic ratio: 1Aa : 1aa PHENOtypic ratio: 1 Dominant : 1 Recessive

AA x AA

GENOtypic ratio: all AA PHENOtypic ratio: all Dominant

*aa x AA or AA x aa

GENOtypic ratio: all Aa PHENOtypic ratio: all Dominant

aa x aa

GENOtypic ratio: all aa PHENOtypic ratio: all Recessive

Genotype & Phenotype

HOMOzygous DOMINANT = PP DOMIANT Phenotype HETEROzygous = Pp DOMINANT Phenotype HOMOzygous RECESSIVE = pp RECESSIVE Phenotype

ABO Blood types

I^A allele: codes for a functional enzyme A -Enzyme A (I^A allele) adds the A ANTIGEN to the RBC I^B allele: codes for a functional enzyme B -Enzyme B (I^B allele) adds the B ANTIGEN to the RBC i allele: codes for a NONFUNCTIONAL enzyme Enzyme X adds the CORE OLIGOSACCAHRIDE to a surface protein on the RBC the A antigen & B antigen are sugars located on the surface of the red blood cells (RBC) Type A: need 1 functional ALLELE A; possible genotypes = I^AI^A or I^Ai Type B: need 1 functional ALLELE B; possible genotypes = I^BI^B or I^Bi Type AB: need 1 functional ALLELE A & need 1 functional ALLELE B; possible genotypes = I^AI^B Type O: NO FUNCTIONAL ALLELES; possible genotypes = ii

Testcross

If TT X tt: -expect all Tall = Tt offspring If Tt X tt: -expect 1/2 Tall & 1/2 short offspring a TALL plant is crossed with a SHORT plant. There are 3 Tall and 1 short plants in the offspring what is the GENOTYPE of the TALL parent? -if there is ANY SHORT OFFSPRING the GENOTYPE of the TALL parent must be Tt -if the Tall plant was TT there would be NO SHORT offspring

PHENOtype

VISUAL APPEARANCE of organism

A person with blood type B+ needs an emergency blood transfusion, but the hospital doesn't have any more B+ blood. What kind of blood can he safely receive? (Hint: what kind of antibodies are in the plasma of a person with type B+ blood?)

a person with B+ blood will have ANTI-A antibodies the person can accept B, O, Rh+ & Rh- blood B & D

A person with blood type B- needs an emergency blood transfusion, but the hospital doesn't have any more B- blood. What kind of blood can he safely receive? (Hint: what kind of antibodies are in the plasma of a person with type B- blood?)

a person with B- blood will have ANTI-A & ANTI-RH antibodies the person can accept B, O, & Rh- blood O-

Antigens & Antibodies

a person with Type A blood has the A Antigen on RBC -possible genotypes: I^AI^A or I^Ai -Antibodies in blood serum: Anti-B antibodies a person with Type B blood has the B antigen on RBC -possible genotypes: I^BI^B or I^Bi -Antibodies in blood serum: Anti-A antibodies a person with Type AB blood has the A & B Antigens on RBC -possible genotypes: I^AI^B -Antibodies in blood serum: NO antibodies a person with Type O blood has NO antigens on RBC -possible genotypes: ii -Antibodies in blood serum: Anti-A antibodies & Anti-B antibodies

Rh Factor

determined by a different gene than the gene for ABO blood types Rh+ allele: Rh antigen on RBC -a person with Rh+ blood has the Rh antigen on RBC -Possible Genotypes: Rh+Rh+ or Rh+Rh- -Antibodies in Blood Serum: NO antibodies Rh- allele: NO Rh antigen on RBC -a person with Rh- blood has NO Rh antigen on RBC -possible Genotypes: Rh-Rh- -Antibodies in Blood Serum: anti-Rh antibodies

Branching Method

do crosses mathematically what proportion of the offspring will be Tall & Round from the cross: Tt Rr x Tt rr -Gene 1: Tall (T) is dominant over short (t) -Gene 2: Round (R) is dominant over wrinkled (r) -Tt x Tt → 3/4 Tall -Rr x rr → 1/2 Round -3/4 + 1/2 = 3/8 Tall & Round

Blood Transfusions

during a blood transfusion a person receives RBC from donated blood a person can receive blood of a different blood type as long as the ANTIBODIES in his blood serum DO NOT REACT WITH the ANTIGENS on the RBC OF the DONATED BLOOD if a person has ANTIBODIES in his serum THAT REACT WITH the ANTIGENS on the RBC OF the DONATED BLOOD, then AGGLUTONATION (clumping) will occur

Agglutination

each ANTI-A ANTIBODY can bind to 2 A ANTIGENS on incompatible RBC, causing cells to clump (LETHAL)

Law of Segregation

each organism is DIPLOID: has 2 COPIES/ALLELES OF EACH GENE during Meiosis these alleles segregate so that EACH GAMETE contains ONLY 1 ALLELE FOR EACH GENE

RR x rr → Rr

for COMPLETE Dominance, the EXPECTED Phenotypic ratio is all RED the ACTUAL Phenotypic ratio is all PINK, meaning there is INcomplete Dominance

1 Trait Testcross

how do you know the GENOTYPE of an organism if HETEROzygotes & HOMOzygous DOMINANTS look the same? Testcross: cross an organism with the DOMINANT Phenotype with an organism with the RECESSIVE Phenotype the ratio of DOMINANT: RECESSIVE PHENOTYPE will tell you the GENOTYPE of the DOMINANT PARENT

Codominance

in Codominance, the Heterozygote SHOWS both the DOMINANT & RECESSIVE TRAITS -there is 1 gene with 2 alleles but BOTH ALLELES are EXPRESSED -C^BC^B = Black -C^BC^w = salt & pepper -C^wC^w = white Ex: Salt & Pepper Schnauzer fur is a mix of black & white hairs

Dihybrid Cross

study the inheritance of TWO TRAITS Ex: -seed Color = Yellow (Y) or green (y) -seed Shape = Round (R) or wrinkled (r)

Incomplete Dominance

in some Monohybrid Crosses, it is possible to get 3 phenotypes instead of the expected 2 phenotypes there is 1 gene with 2 alleles C^RC^R = Red C^RC^w = pink (intermediate phenotype) C^wC^w = white in Incomplete Dominance, the phenotype of the heterozygote is a BLENDING of the dominant & recessive traits C^BC^B = Black C^BC^w = gray (intermediate phenotype) C^wC^w = white if a PINK flower is crossed with another PINK flower, what is the GENOtypic & PHENOtypic ratio of the offspring? (C^RC^w X C^RC^w) -Genotypic Ratio = 1 C^RC^R: 2 C^RC^w: 1 C^wC^w -Phenotypic Ratio = 1Red: 2Pink: 1white

AntiGEN

located on the surface of RBC & DETERMINES BLOOD TYPE (self)

Blood Type A

need 1 functional ALLELE A (I^A): -I^AI^A -I^Ai

Blood Type B

need 1 functional ALLELE B (I^B): -I^BI^B -I^Bi

Blood Type AB

need a functional ALLELE A (I^A) & B (I^B): -I^AI^B

Dihybrid Cross: YyRr x YyRr

seed Color: Yellow (Y) or green (y) seed Shape: Round (R) or wrinkled (r) Parental cross: YYRR x yyrr -what kind of GAMETES can the YYRR parent make? only YR -what kind of GAMETES can the yyrr parent make? only yr -YyRr Cross: YyRr x YyRr -what is the GENOtypic ratio of the offspring? 9Y_R_ : 3Y_rr : 3yyR_ : 1yyrr -what is the PHENOtypic ratio of the offspring? 9YellowRound: 3Yellowwrinkled: 3greenRound: 1greenwrinkled a MONOhybrid cross between 2 HETEROzygotes produces a 3: 1 ratio -Yy x Yy → 3Y_: 1yy -Rr x Rr → 3R_: 1rr a DIhybrid cross can be split into 2 MONOhybrid crosses -Yy x Yy → 3Y_: 1yy 12Yellow: 4green 3Yellow: 1green -Rr x Rr → 3R_: 1rr 12Round: 4wrinkled 3Round: 1wrinkled

GENOtypic Ratio

shows exactly which combination of ALLELES is in each class 1PP : 2Pp : 1pp

Two-Trait Testcross

used to determine whether an individual is HETEROzygous or HOMOzygous DOMINANT for either of 2 traits -Body Color: Gray (G) is dominant over black (g) -Wing Length: Long (L) is dominant over short (l) what cross can you perform to determine the genotype of a fly with 2 dominant phenotypes? -Gray body: GG or Gg -Long wings: LL or Ll -Possible Genotypes: GGLL, GGLl, GgLL, GgLl cross the parent with the 2 DOMINANT phenotypes with an individual that is HOMOzygous RECESSIVE for both traits -G_L_ x ggll → GgLL x ggll a Long-winged (L), Gray bodied (G) fly is crossed with a short-winged (l), black-bodied (g) fly. What is the genotype of the Long-winged, Gray bodied parent if the phenotypic ratio of the offspring is -1 Long-winged, Gray bodied: GL -1 Long-winged, black-bodied: gL -write the GAMETES made by the BLACK, SHORT winged fly on the LEFT: gl -write the GAMETES made by the GRAY, LONG winged fly on the TOP: GL, G_, _L, _ _ → GL, GL, gL, gL Offspring: GgLl, GgLl, ggLl, & ggLl All of the offspring have Long wings -L_ x ll → LL x ll → Ll (all Long) G_ x gg → Gg x gg → 1/2 Gray (Gg) + 1/2 black (gg) Genotype of Gray, Long-winged fly: GgLL

Punnett Square: Tt x Tt

what kind of GAMETES can MOM make? Tt what kind of GAMETES can DAD make? Tt T = tall; t = short what is the GENOtype of each offspring? GENOtypic ratio: 1TT : 2Tt : 1tt identify the PHENOtype of each offspring -PHENOtypic ratio: 3tall : 1short

Punnett Square of Testcross

what kind of GAMETES can a DOMINANT parent make? -T & ? what kind of GAMETES can a RECESSIVE parent make? -only t if the DOMINANT parent is a HETEROzygote the ? = t -expected Phenotypic ratio from Tt X tt = 1 Tall: 1 short if the DOMINANT parent is HOMOzygous DOMINANT the ? = T -expected Phenotypic ratio from TT X tt = all Tall (& no short)