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While on Safari in the wild jungles of Africa, Professor Claudia woke one morning and felt something in the pocket of her pajamas. It had a head and a tail, but no legs. When Claudia got up she could feel it move inside of her pocket. However, Claudia showed little concern and went about her morning activities. Why wasn't she concerned?
What is incomplete dominance?
What is genotype? What is heterozygous? What is phenotype?
A cross between a blue blahblah bird & a white blahblah bird produces offspring that are silver.
A. What are the genotypes of the parent blahblah birds in the original cross?
B. What is/are the genotype(s) of the silver offspring?
C. What would be the phenotypic ratios of offspring produced by two silver blahblah birds?
There are more than _2_alleles for a trait
Blood type in humans Blood Types?
Type A, Type B, Type AB, Type O
Blood Alleles?A, B, O (in book – IA, IB, i)
A and B are codominantAA = Type ABB = Type BAB = Type AB
A and B are dominant over OAO = type ABO = type BOO = type O
TYPE _A_ Allele = IA
Blood cells have small antigens on the surface.
TYPE _B_ Allele = IB
Cells coated with type B antigens
TYPE _AB_ genotype = IAIB
Blood cells contain both types of antigens
Known as universal recipient
TYPE _O Allele = i No antigens on
the surface of the blood cells
Known as universal donor
Table 14.2
Multiple alleles
ABO blood groups
There are _3_ different alleles, IA, IB, and i
Allele IA makes a cell surface antigen, symbolized with a triangle
IB makes a different antigen, symbolized as a circle
i makes no antigen
Blood Typing 14. Use the results shown
to determine the blood type for each sample.
- = No Clumps
+ = Clump
A
B
Rh
Blood Type: ___
To determine a person’s blood type, we add three different serums to blood samples and see if clumps form.
Clumps = Positive (+)No Clumps = Negative (-)
What would the blood type be for this sample?
#13
The Human ABO Blood Group System
Multiple alleles
ABO blood groups
A
B
Rh
Blood Type: ___
A
B
Rh
Blood Type: ___
A
B
Rh
Blood Type: ___
A
B
Rh
Blood Type: ___
A
B
Rh
Blood Type: ___
Blood Typing Use the results shown to determine the blood type for each sample.
- = absent
+ = present
Show the cross between a mother who has type O blood and a father who has type AB blood.
- AO (2) BO (2)- ratio 1:1
- type A (2); type B (2)- ratio 1:1
GENOTYPES:
PHENOTYPES:
O O
A
B
AO
BO
AO
BO
Show the cross between a mother who is heterozygous for type B blood and a father who is heterozygous for type A blood.
-AB (1); BO (1); AO (1); OO (1)- ratio 1:1:1:1
-type AB (1); type B (1) type A (1); type O (1)- ratio 1:1:1:1
GENOTYPES:
PHENOTYPES:
A O
B
O
AB
OO
BO
AO
Traits controlled by two or more _genes_.
Examples:Human height,eye and skin color
The greatest difference between individual members of the same species is their sex.
In humans, females have two “X” chromosomes in the 23rd pair.
In humans, males have an “X” and a “Y” chromosome on the 23rd pair.
If females have the XX combination, then all eggs will contain an X chromosome.
XX
X
X
If males contain the XY combination then the sperm can contain either the X or the Y chromosome.
XY
X
Y
The male always determines the sex of the offspring--if he passes the X chromosome the result is a female offspring.
If he passes the Y chromosome the result is a male offspring.
The study of the fruit fly by Thomas Hunt Morgan led to the discovery of sex determination and sex linkage.
Most flies had red eyes. Morgan noticed a male with white eyes. He performed an experimental cross.
RED EYEDFEMALE
WHITE EYEDMALEP1
?????????????????
A red eyed female crossed with a red eyed male?
75% had red eyes, 25% had white eyes.
50% were male, 50% were female All of the white eyed flies were MALE.
A trait that is carried on the X chromosome.
Almost always expressed in males.
Hemophilia Duchenne Muscular Dystrophy Red/Green Color Blindness
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