Exam 1 Pp Slides

7/31/2019 Exam 1 Pp Slides

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Exam 1 Slide 1

Biology 221:Genetics, Development, and Evolution

I. Genetics Two major themes:

1. Heredity characteristics of parents arepassed on to offspring.

2. Molecular genetics inheritance based

on information encoded in DNA and themolecular machinery that controls its

expression and replication.


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Exam 1 Slide 2


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Exam 1 Slide 3

Genetics, Development, and Evolution(continued)

II. Development All multicellularorganisms grow and develop from a single

fertilized egg. How?


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Exam 1 Slide 4Fate Map of the nematode wormCaenorhabditis elegans(C. elegans)

Adults: 1.2 mm long

Made up ofexactly 959somatic cells


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Exam 1 Slide 5


II. Development All multicellularorganisms grow and develop from a single

fertilized egg. How?

1. Differentiation cells divide and take ondifferent characteristics.

2. Morphogenesis differentiated cells areorganized into tissues and organs, and

assume characteristic pattern, shape, and

form.


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Exam 1 Slide 6


III. Evolution Two fundamental problems ofevolutionary biology:

1. Adaptation and apparent design evident atall levels of biological organization.

2. Variation and biological diversity incredible(and chaotic!) variety of organisms.

Species living on earth: 5-100 million

Named and described species: 1.7 million

Insects: 1 million

Beetles: 600,000


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Exam 1 Slide 7

85 of the 183 species (!) of tyrant flycatchers(family Tyrannidae) of Colombia


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Exam 1 Slide 8

III. Evolution Two fundamental problems ofevolutionary biology (continued):

1. Adaptation and apparent design evident atall levels of biological organization.

2. Variation and biological diversity incredible

(and chaotic!) variety of organisms.

Solutions:

1. Adaptation and apparent design evolves

gradually by process ofnatural selection.

2. Biological diversity evolves gradually by

process ofspeciation.


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Exam 1 Slide 9

Biology 221: The Three Big Questions1. How is the genetic information encoded inDNA expressed, regulated, and passed onto subsequent generations?

2. How does genetic information orchestratethe growthand developmentof multicellularorganisms?

3. How does genetic information evolveovertime to produce both adaptationandbiological diversity?


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Exam 1 Slide 10

Two Aspects of Genetics

1. Heredity: the means by which traitsare passed from parents tooffspring.

2. Molecular genetics: replication ofgenetic material, transcription,translation, and regulation of gene

expression.


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Exam 1 Slide 11

Prokaryotic cellOrigin of replication

Prokaryotic

chromosome:Double-stranded DNA Replicationof DNA

Elongation of cell

Septation

Inward growth ofseptum

Cell pinches in two

Cell Division in

Prokaryotes


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Exam 1 Slide 12

Plasma membrane

Cytoplasm

Organelles

Nucleus

Nuclear envelope

Eukaryotic Cells

S


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Exam 1 Slide 13

Nucleo-some

DNA

Centralhistone

DNA double helix (duplex)

DNA

Chromosome

Rosettes ofchromatin loops

Scaffold proteinScaffoldprotein

Chromatin loop

Solenoid

Levels of ChromosomeOrganization in Eukaryotes

Nucleosome DNA coiled around histone proteins.Solenoid coil of nucleosomes.Chromatin loop looped string of solenoids.

E 1 Slid 14


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Exam 1 Slide 14

Homologous

chromosomes

Homologous chromosomes

Centromere

Sisterchromatids

Sisterchromatids

Replication

Homologous Chromosomes vs. SisterChromatids of Replicated Chromosomes

Maternal Paternal

Homologous chromosomes a pair ofchromosomes, one inherited from eachparent, that carry equivalent genes.

Sister chromatids the two replicates of a

duplicated chromosome, held together bya centromere.

Chromosomes are counted

by counting centromeres

E 1 Slid 15


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Exam 1 Slide 15

Karyotype of a Human Male

N= 46 chromosomes

23 homologouspairs (22 pairs ofautosomes and 1pair of sexchromosomes)

E 1 Slid 16


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Exam 1 Slide 16

G2

S G1

M

Metaphase

Prophase

Anaphase

Telophase

Interphase (G1, S, G2 phases)

Mitosis (M)

Cytokinesis (C)

C

The Eukaryotic Cell Cycle

G1 Primarygrowth phase

S Completereplica of genome

synthesized

G2 Secondarygrowth phase

M Nuclear (mitotic) division)

C Cytoplasmicdivision

E 1 Slid 17


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Exam 1 Slide 17

INTERPHASE (G2)

Nucleus

Nucleolus

Aster

Centrioles(replicated;

animalcells only)

Chromatin(replicated)

Nuclearmembrane

DNA already replicated(during S phase)

Centrioles, if present,replicate

Cell prepares for division

Prelude to Cell Division: Late Interphase

Exam 1 Slide 18


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Exam 1 Slide 18

MITOSIS

Prophase Metaphase

Nuclear membranedisintegrates, andnucleolus disappears

Chromosomes condense Mitotic spindle begins to

form and is complete at theend of prophase

Kinetochores begin tomature and attach to spindle

Kinetochores attachchromosomes to mitoticspindle and align them alongmetaphase plate at equatorof cell

Centromere and

kinetochore

Mitotic spindlebeginning to form

Polarmicrotubules

Kinetochoremicrotubules

Condensed chromosomes Chromosomesaligned on

metaphaseplate

Mitoticspindle

Mitosis: Prophase and Metaphase

Exam 1 Slide 19


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Exam 1 Slide 19

Metaphase chromosome(two sister chromatids)

Kinetochore

Kinetochoremicrotubules

Centromereregion of

chromosome

ChromatidChromosome Structure

During Metaphase

Exam 1 Slide 20


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Exam 1 Slide 20

MITOSISAnaphase Telophase

Polar

microtubules

Kinetochore microtubules

Nuclei

reforming

Kinetochore microtubulesshorten, separatingchromosomes to oppositepoles

Polar microtubules elongate,preparing cell for cytokinesis

Chromosomes reachpoles of cell

Kinetochores disappear Polar microtubules continue

to elongate, preparing cellfor cytokinesis

Nuclear membrane re-forms Nucleolus reappears

Chromosomes decondense

Chromo-somes

Polar

microtubules

Mitosis: Anaphase and Telophase

Exam 1 Slide 21


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Exam 1 Slide 21

CYTOKINESIS

Cell plate

Cleavage furrow

Plant cells: cell plateforms, dividingdaughter cells

Animal cells: cleavagefurrow forms at equatorof cell and pinchesinward until celldivides in two

Cytokinesis

PlantCells

AnimalCells

Exam 1 Slide 22


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Exam 1 Slide 22

Mitosis Quiz: Name That Stage!

Mitosis: The Take-Home Message

Two geneticallyidenticaldaughtercells are producedfrom a single

original cell!

Exam 1 Slide 23


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Exam 1 Slide 23

Summary of Mitosis Genetic material in Eukaryotes is organized into

chromosomes composed of chromatin (DNA and itsassociated packaging proteins).

Cell division in Eukaryotes is accomplished through acomplex process called mitosis.

Before mitosis begins, the cells entire genome isreplicated during the S phase of the cell cycle.

A replicated chromosome consists of two identicalsister chromatids connected by a centromere.

Mitosis orchestrates the separation of sister

chromatids into independent chromosomes in twoseparate daughter cells.

The final step of cell division is the physical separationof the daughter cells via cytokinesis.

Exam 1 Slide 24


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Exam 1 Slide 24

The Trouble With SexSexual reproductionFusion of specialized sex

cells (gametes) to form a fertilized zygote whichsubsequently divides, grows, and develops intoan adult.

Sexually reproducing

organisms must thereforehave a mechanism toreduce the number ofchromosomes by half

before forming gametes.

Meiosis!

Exam 1 Slide 25


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Exam 1 Slide 25

Sexual Life Cycle and Meiosis

Adult body cellsare diploidhave two copies(homologouspair) of eachchromosome.

Gametes arehaploid haveone copy of eachchromosome.

Exam 1 Slide 26


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Exam 1 Slide 26

Unique Features of Meiosis

Reduction division

Meiosis involves twosuccessive divisions, with noreplication of genetic materialbetween them.

Synapsis Homologous chromosomes

pair along their length.

Homologous recombination Genetic exchange (crossing

over) occurs betweenhomologous chromosomes

during first meiotic division.

Exam 1 Slide 27


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Exam 1 Slide 27

Synapsis, Crossing over, and Chiasmata

Identical sister

chromatids

Tetrad

Parental chromatid

Note: There can be

multiple Chiasmatabetween a pair of

homologous

chromosomes!

Red= Maternal

Blue = Paternal

Arrows point to

regions of crossing

over. Note that

sister chromatids

cannot be resolved

Identical sisterchromatids

Parental chromatid

Sisterchromatids arenow no longer

identical!

Exam 1 Slide 28

Mit i M i i I


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a S de 8

Chromosomereplication

Parent cell

(2n)

Prophase

Metaphase

AnaphaseTelophase

Prophase I

Metaphase I

Anaphase ITelophase I

Homologouschromosomes

do not pair.

Individualhomologuesalign onmetaphaseplate.

Sister chromatidsseparate, cytokinesisoccurs, and twocells result, eachcontaining theoriginal number of

homologues.Two daughtercells (each 2n)

Replicatedhomologue

Sisterchromatids

Paternal homologue

Maternal homologue

Homologous

chromosomes


pair; synapsisand crossingover occur.

Homologouschromosomesseparate; sisterchromatidsremain

together.

Paired homologouschromosomesalign at random onmetaphase plate.

MITOSIS MEIOSIS

MEIOSIS IChromosome

replication

Parent cell

(2n)

Mitosis vs. Meiosis I

Exam 1 Slide 29


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Metaphase and Anaphase: Mitosis vs. Meiosis I

Metaphase I

Anaphase I

Meiosis I

Chiasmata

Homologs are paired, heldtogether by chiasmata.

The kinetochores of sister

chromatids fuse and function asone. Microtubules can attach to only

one side of each centromere.

Microtubules pull the homologouschromosomes apart, but sisterchromatids are held together.

MitosisMetaphase

Anaphase

Homologues are not paired.

Kinetochores of sister

chromatids remain separate. Microtubules attach to bothkinetochores on opposite sidesof the centromere.

Microtubules pull sister

chromatids apart.

Exam 1 Slide 30


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Nonidenticalsisterchromatids

After Telophase of Meiosis I

1. Each chromosome consists of two non-identicalchromatids.

2. Chromosomes are no longer purely paternal ormaternal; they typically contain a mix of maternal and

paternal genes.

the two daughter cells

are now haploid! Daughter cells have only

one copy of each pair ofhomologous

chromosomes.

Because of crossing overduring Prophase I

Exam 1 Slide 31

Meiosis II


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Meiosis IIMetaphase II Anaphase II Telophase II

Meiosis II resembles normal mitotic division,but with half the normal diploid number ofchromosomes.

Final result four genetically non-identical

haploid cells!

Exam 1 Slide 32


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Summary of Meiosis Only germ-line cells that give rise to

haploid gametes undergo meiosis. Outcome of a meiotic cell division: four

non-identical haploid cells.

Daughter cells contain a mix of maternal

and paternal characteristics, because of: Crossing over and exchange of genetic

material (recombination) by homologouschromosomes during Prophase I.

Independent assortment of homologouschromosomes during Anaphase I.

Maternal and paternal chromosomesdo notstick together.


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Exam 1 Slide 34


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Mendels Experimental Design

allowed pea plants to self-fertilize forseveral generations.

assured pure-breeding traits.

performed crosses between varietiesexhibiting alternative character forms.

permitted hybrid offspring to self-

fertilize for several generations. counted the number of offspring

exhibiting particular traits.

Exam 1 Slide 35


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Mendels Experimental Results: F1

F1 Generation (first filial)All offspring had purpleflowers!

No blendinginheritance.

Parental Generation

Crossed two true-breeding varieties ofpeas, one with whiteflowers and one with

purple flowers: amonohybrid cross.

Mendels conclusion: purple isdominant, white is recessive!

Exam 1 Slide 36


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Mendels Experimental Results: F2

F2

Generation(second filial)

Mendel allowedpurple F1 to self-fertilize.

F2 offspringpurple:white in

an approximate3:1 ratio!

Exam 1 Slide 37

M d l E i t l


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Mendels ExperimentalResults: F3

All of the recessivewhite F2 plants weretrue-breeding!produced only white

offspring when self-fertilized.

However, only 1/3 of thedominantpurple F2plants were true-breeding!2/3 produced purple:

white offspring in a 3:1ratio when self-fertilized.

Exam 1 Slide 38


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The SevenTraits

Studied ByMendel

All showed the

same 3:1 ratio ofDominant:Recessive in theF2 Generation.

Exam 1 Slide 39

M d l M d l f H dit


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Mendels Model of Heredity Parents transmit discrete inheritance factors

(genes) to offspring.

Each individual receives two such factors foreach trait, one from the gamete of each parent.

The existence of alternative forms (alleles) ofthese factors means that some individuals have

two identical forms (homozygous) while otherindividuals have two different forms(heterozygous).

The two factors for a trait separate from each

other when gametes form:Mendels Law ofSegregation (or Mendels First Law).

Presence of a particular allele does not ensure itwill be expressed in a heterozygote: Mendels Law

of Dominance.

Exam 1 Slide 40


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Notational convention P - dominant allele (purple)

p - recessive allele (white)

PP - homozygous dominant

Pp - heterozygous

pp - homozygous recessive

MendelsMonohybrid

Cross

P PP x pp

F1 genotype: all Pp heterozygotes

phenotype: all Purple

F1 Pp x Pp

F2 genotype: 1:2:1 ratio

1 PP homozygote

2 Pp heterozygotes

1 pp homozygote

phenotype: 3:1 ratio ofPurple:White

Exam 1 Slide 41

Mendel and the Testcross


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Mendel and the TestcrossQ. How can we determine if an individual with the

dominant phenotype is homozygous or

heterozygous?A. The Testcross cross it with a homozygousrecessive!

Exam 1 Slide 42


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Independent Assortment and theDihybrid Cross

Mendels First Law Alternative alleles oftrait (gene) segregate independently.

Mendel then asked: Do alleles of twodifferent traits also segregateindependently?

Mendel tested this possibility with a seriesof dihybrid crosses.

Exam 1 Slide 43


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The Dihybrid Cross and Independent Assortment

Pure-breedingindividuals thatdiffer in twotraits arecrossed.

Round (R) is dominantto wrinkled (r)

Yellow (Y) is dominant togreen (y)

If alleles of the twotraits assortindependent,then F2 offspring

should showphenotype ratiosof 9:3:3:1.

Exam 1 Slide 44

M d l S d L


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Mendels Second Law:Independent Assortment

During gamete formation, thesegregation of the pair of alleles forone trait is independent of the

segregation of the pair of alleles foranother trait. *

* Strictly speaking, applies only when the

genes affecting the two traits are locatedon different chromosomes.

Exam 1 Slide 45

Mendels Laws and Behavior of Chromosomes During Meiosis


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Mendels 1st Law:Law of Segregation

Mendels 2nd Law:Independent Assortment

GenotypeSs

GenotypeSsYy

Random

alignment ofhomologous

pairs onMetaphase plate

Metaphaseof Meiosis I

Mendel s Laws and Behavior of Chromosomes During Meiosis

Exam 1 Slide 46

The Chromosomal Theory of


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The Chromosomal Theory ofInheritance

Following the rediscovery of Mendels work in

1900, researchers immediately saw parallelsbetween Mendels laws of inheritance andthe behavior of chromosomes duringmeiosis.

Walter Sutton (1902) formally proposed thechromosomal theory of inheritance; weregenes indeed located on chromosomes?

Confirmed by T. H. Morgan in 1910 with

demonstration of traits linked to sexchromosomes in fruit flies.

Exam 1 Slide 47

M E i t l R lt


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Morgans Experimental Results

White-eyed male Red-eyed female

XP

F1

Progeny all red-eyed

What the #$%^$#is going on here?

F2

Males about half white-

eyed, half red-eyed!

Females all

red-eyed!

?

F1 female White-eyed male

X

50% red, 50% white, both

males and females!

Exam 1 Slide 48

Morgans Experiment


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Morgans Experiment

R = Red eye (dominant

r = white eye (recessive)

XrY XRXR

XRY XRXr

Both males and femaleshave red eyes

XrY XRY XRXr XRXR

Males: 50% red eyes, 50%white eyes.

Females: all red eyes.

Exam 1 Slide 49

Basic Mendelian Genetics: Essential Terminology


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Basic Mendelian Genetics: Essential Terminology

GeneThe basic unit of heredity; asequence of DNA nucleotides that

encodes a protein or RNA molecule.

LocusSite on a chromosomeoccupied by a particular gene.

AlleleAn alternative form of aparticular gene.

Diploid

The condition in which twosets of chromosomes are present in

an individual (or cell); typically one

set is derived from an individuals

mother, the other from the father.

Haploid

The condition in which onlyone set of chromosomes is present

in an individual (or cell).

HomozygoteA diploid individual thatpossesses two copies of the same

allele at a particular gene locus.

HeterozygoteA diploid individualthat possesses two different

alleles at a particular gene locus.

DominantAn allele that hasphenotypic effects in both the

heterozygous and homozygous

condition.

RecessiveAn allele that hasphenotypic effects only in the

homozygous condition.

MeiosisThe two successivenuclear divisions in which a

single diploid cell forms four

haploid nuclei and allelic

segregation, crossing over, and

independent assortment of

homologous chromosomes

occur.

Exam 1 Slide 50

Summary of Basic Mendelian Genetics


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Mendels Laws:

1. Law of Segregation the two alleles of a gene

separateduring gamete formation.2. Law of Independent Assortment pairs of alleles for

different genes segregate independentlyof each other.

Other principles:

1. Dominance: heterozygous phenotype = homozygousdominant phenotype

2. Only two distinct phenotypic classes for each trait

(dominant and recessive).

3. One gene (one pair of alleles) controls one trait.

4. All genes are on chromosomes in the nucleus.

In many situations, one or more of these basic

principles do not apply!

Exam 1 Slide 51

Chromosomal Sex Determination Systems I


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ChromosomalSex Determination Systems I

X-Y System

Mammals, fruit flies, otheranimals.

Males heterogametic XY!

X-0 SystemGrasshoppers, crickets,cockroaches, otherinsects.Males hemizygous X0!

Exam 1 Slide 52


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ChromosomalSex Determination Systems II

Z-W System

Birds, butterflies, somefishes.Females heterogametic

ZW!

Haplo-diploid System

Bees, ants, wasps,

some other animals.Males haploidandhatch from unfertilizedeggs!

Exam 1 Slide 53

Sex-Linked Inheritance of Barred Plumage in Chickens


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Sex Linked Inheritance of Barred Plumage in Chickens

Exam 1 Slide 54

Environmental Sex Determination Systems


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EnvironmentalSex Determination Systems

Sequential hermaphroditism

Many fish, some shrimp.

Depending on environmentalconditions, individuals maychange sex during thecourse of their lifetime!

Temperature-dependent sexdetermination

Turtles, alligators, somefishes.Temperature duringdevelopment determines sex!

Exam 1 Slide 55



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Mendels Laws:




Other principles:

1. Dominance: heterozygous phenotype =homozygous dominant phenotype

2. Only two distinct phenotypic classes for each trait(dominant and recessive).





Exam 1 Slide 56

Incomplete Dominance in Four Oclock Flowers


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F1 generation

F2 generation 1 : 2 : 1

CRCR

All CR

CW

CWCW

Eggs

Sperm

CR

CW

CR CW

CR

CR

CR

CW

CRCW CWCW

1 CRCR Red2 CRCW Pink1 CWCW White

Incomplete Dominancein Four O clock Flowers

Exam 1 Slide 57

Codominance in M N and


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Codominancein M, N, andMNBlood Types of

HumansBlood

type M

Bloodtype MN

Bloodtype N

Two alleles in humanpopulation: LMand LN

Homozygotes(Both LMLMand LNLN) produce only onetype of glycoprotein onsurface of red blood cells

LMLNheterozygotesproducebothtypes of glycoproteinson surface of red blood

cells

Exam 1 Slide 58

Multiple Alleles in the Human ABO Blood Groups


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IAIA

IAIB

IAi

IAIB

IBIB

IBi

IAi

IBi

ii

IA

IA

or

IB

or

i

or IB or i

Possible alleles from female

A AB BBlood types O

Poss

iblealleles

fromm

ale

Multiple Alleles in the Human ABO Blood Groups

Three alleles presentin human population:

IA, IB, or i

IAand IBare

codominantwithrespect to eachother, butcompletely

dominantover i

Exam 1 Slide 59

Inheritance of Yellow Coat Color in Mice


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Yellow Pure-breeding WildType (Agouti)

Half Yellow Half Agouti

Parents

F1

x

Exam 1 Slide 60



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Y+ ++

Half Y+ Half ++

Parents

F1

x

1. Likely Interpretations:Yellow Coat Color Dominant to Wild Type.P and F1 Yellow Mice are Heterozygous Y+.

Exam 1 Slide 61



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Inheritance of Yellow Coat Color in MiceF1

x

2 1

F2

2. F2 results:Yellow:Wild Type ratio 2:1 (not 3:1)!Litter size only about 3/4 normal.

Test crosses show that Yellow F2 allheterozygous!

Conclusions:Yallele produces both a dominantphenotype(yellow coat) and a recessive

phenotype(early embryo mortality)!

Y+ Y+


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Exam 1 Slide 63

Epistasisand Anthocyanin Production in Corn


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F1 generation

All purple

XWhite

Strain B

White

Strain A

p s as s y

Exam 1 Slide 64

Epistasisand Anthocyanin Production in Corn


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AB

AB Ab aB ab

Ab

aB

ab

AABB

AABb

AaBB

AaBb

9/16 purple7/16 white

F1 generation

All purple(AaBb)

X

AABb

AAbb

AaBb

Aabb

AaBB

AaBb

aaBB

aaBb

AaBb

Aabb

aaBb

aabb

Eggs

Sperm

White

(aaBB)

White

(AAbb)

F2 generation

p y

Production of purple

pigment anthocyaninis the result of a two-

step process:

Starting molecule

Intermediate molecule

Anthocyanin

EnzymeCoded byGene A

EnzymeCoded byGene B

Exam 1 Slide 65Epistasis and Coat Coloration in Labrador Retrievers


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ee

No dark pigment in fur

eebb eeB_

Yellow fur;brown nose,lips, eye rims

Yellow fur;black nose,

lips, eye rims

Yellow Lab

E_

Dark pigment in fur

E_bb E_B_

Brown fur,nose, lips,eye rims

Black fur,nose, lips,eye rims

Chocolate Lab Black Lab

Two interacting loci: Elocus (pigment in fur)Blocus (darkness of pigment)

Exam 1 Slide 66



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y

Mendels Laws:




Other principles:








Exam 1 Slide 67

Maternal Effect


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Maternal-EffectInheritance of

Shell Coiling inSnails

Phenotype

(direction ofcoiling)reflects

genotype(notphenotype) of

mother!

Exam 1 Slide 68

C t l i (M t l) I h it


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Cytoplasmic (Maternal) Inheritance

Exam 1 Slide 69



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y

Mendels Laws:




Other principles:








Exam 1 Slide 70


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DihybridTest Cross

inDrosophilaUsing black

(b) andvestigial

wings(vg):

IndependentAssortment?

Not

1:1:1:1!

Exam 1 Slide 71


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Linkage and Production of RecombinantGametes by a Dihybrid Female

F1 Female(Heterozygote)

Exam 1 Slide 72


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Linkage and the Dihybrid Test Cross

Parental Gametes

(many)

Recombinant

Gametes (few)

Exam 1 Slide 73

Linkage and the Testcross Offspring


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Parental Gametes Recombinant Gametes

g p g

Exam 1 Slide 74


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Consequences

of Absence ofRecombination

in MaleDrosophila:

CompleteLinkage in the

ReciprocalCross! No

crossingover inmale fruitflies!

Male Female

Half Half None! None!

Exam 1 Slide 75

Linkage and the Testcross Offspring


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Parental Gametes Recombinant Gametes

Exam 1 Slide 76


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RelationshipBetween

Observedand

CorrectedMapDistances

Exam 1 Slide 77Determining Gene Order with the Three-Point Test Cross


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Three loci in the worm C. elegans: Dumpy, Uncoordinated, and Knobby

P +++ / +++ x duk / duk

F1 +++ / duk x duk / duk Three-point test cross!

Progeny:Wild type 410Dumpy, uncoordinated, knobby 392

Knobby 61Dumpy, uncoordinated 65

Uncoordinated, knobby 3Dumpy 3

Uncoordinated 34Dumpy, knobby 32

Total 1000

Which progeny are double-

crossovers?

The rarest forms:

uncoordinated-knobby anddumpy.

Which locus is in the middle?

Dumpy!

Map distance between D and U:

(34 + 32 + 3 + 3)/1000 = 0.072= 7.2% = 7.2 cM

Map distance between D and K:

(61 + 65 + 3 + 3)/1000 = 0.132= 13.2% = 13.2 cM

Exam 1 Slide 78


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Cystic fibrosis:autosomalrecessive

Exam 1 Slide 79

The Royal Hemophilia Pedigree


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George III

EdwardDuke of Kent

Louis IGrand Duke of HesseI

KingEdward VII

Duke ofWindsor

QueenElizabeth II

PrincePhilip

Margaret

PrincessDiana

PrinceCharles

Anne Andrew Edward

William Henry

KingGeorge VI

King

George V

Earl ofMountbatten

ViscountTremation

Alfonso Jamie GonzaloPrinceSigismond

Prussian

RoyalHouse

British Royal House

Spanish Royal House

Russian

RoyalHouse

Henry Anastasia Alexis

? ?

? ?

? ?

?

Waldemar

Queen VictoriaPrince Albert

FrederickIII

I

II

III

IV

V

VI

VII

Victoria Alice Alfred Arthur Leopold Beatrice PrinceHenry

HelenaDuke ofHesse

No hemophilia No hemophilia

GermanRoyalHouse

Juan

King JuanCarlos

No evidenceof hemophilia

No evidenceof hemophilia

IreneCzarNicholas II

CzarinaAlexandra

Earl ofAthlone

PrincessAlice

QueenEugenie

AlfonsoKing ofSpain

Maurice Leopold

Generation

Sex-linked recessive

Exam 1 Slide 80

Sex linked Dominant: Hypophosphatemia


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Sex-linked Dominant: Hypophosphatemia

Exam 1 Slide 81Karyotype of Individual with Trisomy 21:

D S d


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Fig. 13.35aDown Syndrome

Exam 1 Slide 82


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20 25 30 35 40 450

5

10

15

20

25

Age of mother

IncidenceofDownsyndrome

per1000

livebirths

Maternal Age and Incidenceof Down Syndrome

Exam 1 Slide 83

Female XX


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Male

SpermXY

XXX

XXY

XO

OY

Eggs

Nondisjunction

Female XX

XX O

Female(Triple X

syndrome)

Female(Turner

syndrome)

NonviableMale

(Klinefeltersyndrome)

X

Y

Nondisjunction ofthe Sex

Chromosomes

Exam 1 Slide 84

B kitt L h


84/84

Caused by translocation(swapping) of smallregion of chromosomes8 and 14.

Translocation of genec-mycto chromosome14 disrupts its normalfunction in regulating

cell growth, resulting incancer.

Burkitt Lymphoma

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Exam 1 Pp Slides