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In a nutshell! http://www.athro.com/evo/inherit.html

Today we are going to learn about… Multiple Alleles and Polygenetic

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Today we are going to learn about… Multiple Alleles and Polygenetic. In a nutshell!. http://www.athro.com/evo/inherit.html. Brainteaser. - PowerPoint PPT Presentation

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In a nutshell!

http://www.athro.com/evo/inherit.html

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