Week 24Week 24 When Heredity When Heredity Follows Different Follows Different RulesRules

Ch. 12.2-3 pg 315Ch. 12.2-3 pg 315

complete complete dominancedominance

When the offsping show When the offsping show traits intermediatetraits intermediate between dominant between dominant and recessive,and recessive,

ex Black (BB) X White ex Black (BB) X White (bb) = Gray (Bb)(bb) = Gray (Bb)

incomplete incomplete dominancedominance

the offspring will show only the dominant trait in its phenotype

ex Black (BB) X White (bb) = White (Bb)

Click here for a

Gene E in a bottle

phenotype

genotype

100%heterozygous

allelealleleOne One form of a geneform of a gene, ,

Ex. there are three different Ex. there are three different ______s for blood – A, B, and O______s for blood – A, B, and O

Allele that is expressed Allele that is expressed equally with another equally with another dominant alleledominant allele, , coco-starring-starring

Ex. White (WW) X Black (BB) = Black and White Ex. White (WW) X Black (BB) = Black and White Spotted(BW)Spotted(BW)

WW BB

W

W

BW BW

BWBW

codominant allelecodominant allele

All heterozygous

multiple allelemultiple allele traittrait

Trait controlled Trait controlled by by more than more than two allelestwo alleles

Example: Example: Humans have three alleles for blood - A(IA), B(IB), and (IO)

See video

autosomeautosome

Non-sexNon-sex

chromosomchromosomeses

This is a human karyotype

sex chromosomesex chromosomeChromosomes that Chromosomes that

determine the determine the sexsex of an individual, of an individual, X and YX and Y

Male xy

Female xx

sex-linked sex-linked traittrait

Traits controlled byTraits controlled by genes on sex genes on sex chromosomeschromosomes

ex. ex. Female carrier for Hemophilia (XFemale carrier for Hemophilia (XHHXXhh), ), Hemophiliac male (XHemophiliac male (XHHY)Y)

Hemophiliac female (XHemophiliac female (XHHXXHH))

Male pattern baldingColor blindness – X-linked

4 Sex-Linked Traits: 

1. Normal Color Vision: A: 29,  B: 45,  C: ,  D: 26  

2. 2. Red-Green Color-Blind: A: 70,  B: ,  C: 5,  D:  

3. 3. Red Color-blind: A: 70,  B: -,  C: 5,  D: 6  

4. 4. Green Color-Blind: A: 70,  B: ,  C: 5,  D: 2Hairy earsFemale pattern balding

hemophilia

polygenic inheritancepolygenic inheritanceInheritance pattern of a trait Inheritance pattern of a trait

that is that is controlled by two or more controlled by two or more genes genes

ex. height, skin color, eye colorex. height, skin color, eye color

external external environmentenvironment

TemperatureTemperature, , nutrition, nutrition, light, light, chemicals, chemicals, infectious infectious agentsagents

internal internal environmentenvironmentSurvival based Survival based

on on gender, age,gender, age, interaction interaction with other with other organismsorganisms

sickle cell sickle cell diseasediseaseCauses defective Causes defective

hemoglobin which hemoglobin which changes changes shape of shape of blood cell into a blood cell into a sicklesickle, or half-moon, , or half-moon, blocking blood flowblocking blood flow

Name 4 Human blood types Name 4 Human blood types withwith their genotypes their genotypes

Phenotype Phenotype GenotypeGenotype

Type A Type A IIAAi or Ii or IAAIIAA

Type B Type B IIBBi or Ii or IBBIIBB

Type AB Type AB IIAAIIBB

Type O Type O iiii

Blood type animation

red-green color blindnessred-green color blindness

Caused by recessive genes Caused by recessive genes on X chromosome, affects on X chromosome, affects green and red green and red receptors in receptors in eyeseyes

hemophiliahemophilia

X-linked disorder X-linked disorder that causes that causes problem with the problem with the bloods ability to clotbloods ability to clot

skin colorskin colorA polygenic trait, A polygenic trait,

indicated by indicated by three or three or four genesfour genes

karyotypekaryotypeA chart showing A chart showing

chromosome pairschromosome pairs

Catfish

Down SyndromeDown Syndrome Results from Results from trisomy of trisomy of

chromosome 21chromosome 21, tri = 3, tri = 3

Protein SynthesisProtein Synthesis TranscriptionTranscription

TranslationTranslation

Here are some true/false Here are some true/false questions for youquestions for you

The The DNA DNA moleculemolecule

What determines What determines structure and structure and function of cellsfunction of cells??

OffspringOffspring receive receive genetic genetic information (DNA)information (DNA) from from theirtheir

parents.

Chromosomal Chromosomal mutationsmutations may lead to may lead to

genetic genetic variationvariation

Some Some mutationsmutations are good, and are good, and help an organism survive.help an organism survive. True or False?True or False? True, but not often

Plants reproduce Plants reproduce sexually sexually and asexuallyand asexually.. True or false?True or false?True

DNA in one organism (like a mouse) DNA in one organism (like a mouse) has many similarities with DNA in has many similarities with DNA in another organism (like you). True or another organism (like you). True or False? False?

HumanMouse

True

Every cell Every cell within an within an organismorganism has same DNA. has same DNA. True or False?True or False?

Liver cell Brain cell

True

www.scilinks.orgwww.scilinks.org www.go.hrw.comwww.go.hrw.com www.si.edu/hrwwww.si.edu/hrw

And now the quizzzzzzAnd now the quizzzzzz

_________ _________ dominancedominance

When the offsping show When the offsping show traits intermediatetraits intermediate between dominant between dominant and recessive,and recessive,

ex Black (BB) X White ex Black (BB) X White (bb) = Gray (Bb)(bb) = Gray (Bb)

_________ _________ dominancedominance

the offspring will show only the dominant trait in its phenotype

ex Black (BB) X White (bb) = White (Bb)

Click here for a

Gene E in a bottle

phenotype

genotype

100%heterozygous

_________ _________ One One form of a geneform of a gene

Ex. there are three different ______s for Ex. there are three different ______s for blood blood

A, B, and iA, B, and i

_________ allele_________ allele

Allele that is expressed Allele that is expressed equally with another equally with another dominant alleledominant allele, , coco-starring-starring

Ex. White (WW) X Black (BB) = Black and White Ex. White (WW) X Black (BB) = Black and White Spotted(BW)Spotted(BW)

WW BB

W

W

BW BW

BWBW

_________ allele_________ allele traittrait

Trait controlled Trait controlled by by more than more than two allelestwo alleles

Example: Example: Humans have three alleles for blood - A(IA), B(IB), and (IO)

See video

_________ _________

Non-sexNon-sex

chromosomchromosomeses

This is a human karyotype

____ _________ ____ _________ Chromosomes that Chromosomes that

determine the determine the sexsex of an individual, of an individual, X and YX and Y

Male xy

Female xx

_________ trait_________ traitTraits controlled byTraits controlled by genes on sex genes on sex

chromosomeschromosomes ex. ex. Female carrier for Hemophilia (XFemale carrier for Hemophilia (XHHXXhh), ),

Hemophiliac male (XHemophiliac male (XHHY)Y) Hemophiliac female (XHemophiliac female (XHHXXHH))

Male pattern baldingColor blindness – X-linked

4 Sex-Linked Traits: 

1. Normal Color Vision: A: 29,  B: 45,  C: ,  D: 26  

2. 2. Red-Green Color-Blind: A: 70,  B: ,  C: 5,  D:  

3. 3. Red Color-blind: A: 70,  B: -,  C: 5,  D: 6  

4. 4. Green Color-Blind: A: 70,  B: ,  C: 5,  D: 2Hairy earsFemale pattern balding

hemophilia

_________ _________ inheritanceinheritanceInheritance pattern of a trait Inheritance pattern of a trait

that is that is controlled by two or more controlled by two or more genes genes

ex. height, skin color, eye colorex. height, skin color, eye color

_________ _________ environmentenvironment

TemperatureTemperature, , nutrition, nutrition, light, light, chemicals, chemicals, infectious infectious agentsagents

_________ _________ environmentenvironmentSurvival based Survival based

on on gender, age,gender, age, interaction interaction with other with other organismsorganisms

________ ___ ________ ___ diseasediseaseCauses defective Causes defective

hemoglobin which hemoglobin which changes changes shape of shape of blood cell into a blood cell into a sicklesickle, or half-moon, , or half-moon, blocking blood flowblocking blood flow

4 Human ________ _______ 4 Human ________ _______ withwith their genotypes their genotypes

Phenotype Phenotype GenotypeGenotype

Type A Type A IIAAi or Ii or IAAIIAA

Type B Type B IIBBi or Ii or IBBIIBB

Type AB Type AB IIAAIIBB

Type O Type O iiii

Blood type animation

____ _____ _____ _________ ____ _____ _____ _________

Caused by recessive genes Caused by recessive genes on X chromosome, affects on X chromosome, affects green and red green and red receptors in receptors in eyeseyes

_________ _________

X-linked disorder X-linked disorder that causes that causes problem with the problem with the bloods ability to clotbloods ability to clot

_________ _________ A polygenic trait, A polygenic trait,

indicated by indicated by three or three or four genesfour genes

_________ _________ A chart showing A chart showing

chromosome pairschromosome pairs

Catfish

_________ Syndrome_________ Syndrome Results from Results from trisomy of trisomy of

chromosome 21chromosome 21, tri = 3, tri = 3

For homework:For homework: Draw Protein SynthesisDraw Protein Synthesis

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