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The Work of Gregor Mendel 11-1
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parents to offspring heredity how SCIENCE passed on Genetics
Transmission of characteristics from _______________________is called ___________________. The _________ that studies _____ those characteristics are _________ from one generation to the next is called ___________________ parents to offspring heredity how SCIENCE passed on Genetics
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Father of Genetics Gregor Mendel study understanding how genes work
The __________________ is _________________, a monk whose _________ of genetic traits was the beginning of our _________________ about _____________________. Father of Genetics Gregor Mendel study understanding how genes work
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experiments Pea plants MALE Pollen FEMALE egg Mendel designed
Mendel designed ____________ using __________ in the monastery garden _______ part of flower makes ___________ (sperm) __________ part of flower makes _______ cells experiments Pea plants MALE Pollen FEMALE egg
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same Self pollinating ONE parent
In pea plants, the pollen normally joins with an egg from the _______ plant (=_______________ ) so seeds have “_________________” same Self pollinating ONE parent
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MENDEL’S PEA EXPERIMENTS
Mendel started his experiments with peas that were _________________ = if allowed to _________________ they would produce ____________________ to themselves. true breeding self pollinate offspring identical
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COPY THIS: MENDEL’S PEA EXPERIMENTS
removed pollen Mendel ____________________ making parts and ____________ from _______ plant. This allowed him to _____________ plants with ______________ characteristics and ________ the results added pollen another cross-breed different study
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A _____________________ is called a ____________
Mendel ______________ in peas. specific characteristic trait studied 7 traits Pearson Education Inc,; Publishing as Pearson Prentice Hall
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Copy This:MENDEL’S EXPERIMENTS
____ generation (_________) ____ generation (______= offspring) ___ generation parental F1 filial F2
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Principles of Dominance
Section 11-1 P Generation F1 Generation F2 Generation Tall Short Tall Tall Tall Tall Tall Short
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crossed PURE contrasting F1 Missing returned F2 3:1
When Mendel ______________ PLANTS with 2 ______________ traits: (EX: Tall crossed with short) He always found same pattern: 1. ONLY ______ trait ____________ in the ____ generation BUT . . . 2. ___________ trait ____________ in the ____ generation in a _________ ratio contrasting ONE showed F1 Missing returned F2 3:1
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PATTERNS ARE THE KEY Image modified from:
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__________ must be able to _______ the other. pair of FACTORS control
Mendel decided that there must be a __________________ that ________each trait and that __________ must be able to _______ the other. pair of FACTORS control one factor HIDE
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We now know that Mendel’s ________________ carried on
the pair of________________ _________________ factors are genes homologous chromosomes
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trait are called ___________.
________ gene _______ for a trait are called ___________. DIFFERENT CHOICES ALLELES
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DOMINANT HIDES RECESSIVE is hidden by
__________________ = An allele that ________ the presence of another allele __________________ = An allele that __________________ the presence of another allele HIDES RECESSIVE is hidden by
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The pattern corresponds to the ____________ of ______________ during
Why did the recessive trait disappear in the F1 generation and reappear in the F2? The pattern corresponds to the ____________ of ______________ during ____________________ movement chromosomes MEIOSIS Image modified from:
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WHAT DOES MEIOSIS HAVE TO DO WITH IT?
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REMEMBER HOMOLOGOUS SEPARATE SEGREGATION _____________ chromosomes
________________ during ANAPHASE I = _________________ HOMOLOGOUS SEPARATE SEGREGATION Image modified from:
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F1 received carrying shortness
____ offspring __________ an allele for tallness from their _______ parent and an allele for shortness from their ________ parent. The F1 plants ALL ___________ but are ___________ an allele for _____________ F received TALL SHORT LOOK TALL carrying shortness Images from: BIOLOGY by Miller & Levine; Prentice Hall Publishing ©2006
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made gametes reappears EXPLAINING the F1 CROSS
LAW OF ___________________ SEGREGATION alleles are separated when the F1 plants ______________ When these gametes recombined to make the F2 generation, the _____________ trait _______________ in ¼ of the offspring made gametes recessive reappears Image from: BIOLOGY by Miller & Levine; Prentice Hall Publishing ©2006
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PROBABILITY & PUNNETT SQUARES 11-2
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PROBABILITY ____________________ is the __________ that a particular _________________ likelihood event will occur It can be written as a: Fraction ____ Percent ____ Ratio ____ 1/4 25% 1:3
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COIN FLIP 1/2 50% 1:1 capital There are 2 possible outcomes:
COIN FLIP There are 2 possible outcomes: HEADS TAILS capital The chance the coin will land on either one is: ____ ____ ____ Alleles segregate randomly just like a coin flip. . . So can use probability to predict outcomes of genetic crosses. 1/2 50% 1:1
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PROBABILITIES _____ outcomes ______ affect _________ones
_____________works ______ in ___________ a ________ number of events. PAST DON’T FUTURE If last coin flip was heads… there is still a 50/50 chance the next flip will be heads too. Probability predicting best large The more flips. . . The closer results will be to the expected 50:50 average.
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DOMINANT/RECESSIVE T t capital Dominant Recessive lower-case
_____________ allele is represented by a ____________ letter. (usually the first letter of the trait) ____________ allele is represented by the SAME _________________ letter. EX: Tall = ______ Short =______ capital Recessive lower-case T t NOT S for short
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HOMOZYGOUS HETEROZYGOUS
When both alleles in the pair are the _______, the organism is _______________ or __________ EX: ____ or ___ When both alleles in the pair are _____________, the organism is _________________ or _____________ Ex: ____ SAME HOMOZYGOUS PURE TT tt DIFFERENT HETEROZYGOUS HYBRID Tt
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PHENOTYPE/GENOTYPE The ________________ of an organism is its _____________ The ____________of an organism is its _____________ genetic makeup GENOTYPE appearance PHENOTYPE
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MAKING A CROSS for only a __________ trait = ____________________
ONE GENE MONOHYBRID CROSS A Punnett square for a MONOHYBRID CROSS looks like this:
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PUNNETT SQUARES are used to show possible offspring from a cross between 2 parents _______________ go at top and on left side Boxes show ____________ ___________________ Parent alleles T T T t possible offspring combinations
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STEPS FOR MAKING CROSSES
Figure out parent alleles Choose Punnett size Put in parent gametes Fill in offspring combinations probabilities phenotypes genotypes 1. ___________ what _________________ are 2. ________correct__________ square __________ 3. ______ possible_______________________ 4. ______ boxes with _____________________ 5. Determine ____________of_____________& ____________
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T t TALL = ____ SHORT = ____ IN PEA PLANTS Tall is dominant over short
LET’S MAKE A CROSS! PURE TALL PURE SHORT X
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PURE TALL parent What are the parent alleles?
T T _________ HOMOZYGOUS What gametes can it make? T T
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PURE SHORT parent What are the parent alleles?
t t _________ HOMOZYGOUS What gametes can it make? t t
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T t T t T t T t T t ALL _____ of the offspring ____ % ___/4 will be
100 4 T t T t Tt TALL GENOTYPE _____ PHENOTYPE _______
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HYBRID TALL parent What are the parent alleles?
T t _________ HETEROZYGOUS What gametes can it make? T t
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T t T t T t T T T t t t GENOTYPES ¼ = _____ ½ = _____ TT Tt tt 3/4 75
TALL PHENOTYPES ____ or ____% _________ ____ or ____% _________ 1/4 25 SHORT
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PRACTICE MAKING GAMETES for a MONOHYBRID CROSS
Tall = ____ Round seeds = ___ Short = ____ Wrinkled seeds = ___ T t r
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What are the possible gametes?
Homozygous Tall parent = What gametes can it produce? T T T T
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What are the possible gametes?
PURE wrinkled parent = What gametes can it produce? rr r r
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What are the possible gametes?
Heterozygous Round parent = What gametes can it produce? R r R r
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What are the possible gametes?
Hybrid Tall parent = What gametes can it produce? Tt T t
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Exploring Mendelian Genetics 11-3
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GENES are more complicated than Mendel thought
ENVIRONMENT influences ____________________________ the ________________________. = ________________________ Genes ________ the ______ for development, but how plan unfolds also _______ on ______________conditions. expression of genes “Nature vs Nurture” provide plan depends environmental
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GENES are more complicated than Mendel thought
Some traits have ____________ allele __________ = ____________________ EX: blood type Allele choices ___ ___ ___ choices MORE than 2 MULTIPLE ALLELE TRAIT A B O
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GENES are more complicated than MENDEL thought
Some traits are determined by ____________________________ = __________________ EX: human height intelligence, skin & eye color MORE THAN ONE GENE POLYGENIC TRAIT
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GENES are more complicated than MENDEL thought
Traits determined by ____________ _________ have _____ “___________” phenotypes MORE than ONE gene many in-between There aren’t just SMART people and DUMB people…. there is a ________________ of intelligences in-between whole range
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GENES are more complicated than MENDEL thought
KINDS OF DOMINANCE ____________________ COMPLETE DOMINANCE INCOMPLETE DOMINANCE CO-DOMINANCE
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COMPLETE DOMINANCE Dominant masks recessive Recessive returns 3:1 F2
__________ allele _______ the ___________ one PATTERN ? ____________ allele ________ in a _____ratio in the ____ generation Recessive returns 3:1 F2
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INCOMPLETE DOMINANCE DON’T SEE 3:1 Heterozygous __________ expected
_____ ratio in F2 generation _____________ organisms with one dominant and one recessive allele show a _________ in-between trait 3:1 Heterozygous BLENDED Image modified from:
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CO-DOMINANCE BOTH _______ traits are expressed at ___________ (_____________________) in heterozygote SAME TIME NO BLENDING ROAN A ________HORSE has ______________ hair and __________ hair side by side BOTH RED WHITE
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CO-DOMINANCE Both traits are expressed together (NO BLENDING) in heterozygote Persons with an A allele AND a B allele have blood type AB
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Membrane proteins with _______ attached that help cells recognize self
REMEMBER Membrane proteins with _______ attached that help cells recognize self = ______________ sugars GLYCOPROTEINS
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BLOOD TYPES have more than 2 allele choices = _________________________
MULTIPLE ALLELE TRAIT The pattern of sugars that is attached is determined by genes Allele choices are: _____ ____ ____ A B O
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BLOOD TYPES An A allele tells the cell to put “A” glycoproteins
on its surface
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BLOOD TYPES A B allele tells the cell to put a
different “B” glycoprotein on its surface
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BLOOD TYPES An O allele tells
the cell NOT to put anything on the surface
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A and B are CO-DOMINANT A cell with BOTH an A and a B allele has BOTH
glycoproteins on its surface
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PHENOTYPE (BLOOD TYPE)
BLOOD TYPES & ALLELES GENOTYPE PHENOTYPE (BLOOD TYPE) AA AO BB BO OO AB A A B B O AB
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A and AB see A as “like me” as Different!
DONOR BLOOD A and AB see A as “like me” B and O see A as Different! IMMUNE SYSTEM ATTACKS! Body images modified from:
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B and AB see B as “like me” as Different!
DONOR BLOOD B and AB see B as “like me” A and O see B as Different! IMMUNE SYSTEM ATTACKS! Body images modified from:
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O ____ can donate to EVERY BLOOD TYPE = _____________________
DONOR BLOOD O ____ can donate to EVERY BLOOD TYPE = _____________________ Nothing on surface to recognize as “NOT SELF” UNIVERSAL DONOR YOU DON’T HAVE ANYTHING I DON’T HAVE! Body images modified from:
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Only AB sees AB as “like me”
DONOR BLOOD Only AB sees AB as “like me” A, B, and O see AB as Different! IMMUNE SYSTEM ATTACKS! Body images modified from:
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AB can only GIVE to AB BUT . . .
______ can RECEIVE FROM EVERY BLOOD TYPE = ________________________ UNIVERSAL RECIPIENT Body image modified from:
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BLOOD TYPE FREQUENCY IN USA
40% B 10% AB 4% O 46%
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ABO SYSTEM is NOT THE ONLY ONE
Rh Rh-
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OTHER BLOOD TYPES NO PROBLEMS MOM is _____ & BABY is ____ Rh+ Rh+ Rh+
____________________ IF: NO PROBLEMS MOM is _____ & BABY is ____ Rh+ Rh+ MOM is _____ & BABY is _____ Rh+ Rh- Image modified from:
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Can be a ___________ IF: Mom is _____ Baby is _____
PROBLEM Can be a ___________ IF: Mom is _____ Baby is _____ Rh- Rh+ 1st baby OK but few baby cells entering mom’s bloodstream put mom’s immune system on alert for + cells. Next + baby, mom’s immune system can attack baby as it is growing Mom given shot after 1st birth prevents this Image modified from:
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DIHYBRID CROSSES (2 traits)
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Mendel also asked the question?
Does the gene that determines if a seed is round or wrinkled have anything to do with the gene for seed shape? Must a seed that is yellow also be round?
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MAKING A CROSS with ___________________= ____________________
TWO gene traits DIHYBRID CROSS A Punnett square for a DIHYBRID CROSS looks like this:
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Figure 11-10 Independent Assortment in Peas
Section 11-3
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LET’S MAKE A DIHYBRID CROSS
HOMOZYGOUS YELLOW ROUND HOMOZYGOUS GREEN WRINKLED rryy RRYY 1. ___________ what _________________ are 2. ________correct__________ square __________ 3. ______ possible_______________________ 4. ______ boxes with _____________________ 5. Determine ____________of_____________& ____________ Figure out parent alleles Choose Punnett size Put in parent gametes Fill in offspring combinations probabilities phenotypes genotypes
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LAW OF __________________________
the factors are distributed to gametes independently of other factors INDEPENDENT ASSORTMENT Image modified from:
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PRACTICE MAKING GAMETES
WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE? HOMOZYGOUS ROUND YELLOW Each gamete should get one of each kind of gene R R Y Y R Y R Y R Y R Y ___________ ____________ _____________ _____________
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PRACTICE MAKING GAMETES
WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE? Each gamete should get one of each kind of gene HOMOZYGOUS WRINKLED GREEN r r y y r y r y r y r y ___________ ____________ _____________ _____________
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PRACTICE MAKING GAMETES
WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE? HETEROZYGOUS ROUND YELLOW Each gamete should get one of each kind of gene R r Y y R Y r y r Y R y ___________ ____________ _____________ _____________
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RY RrYy ROUND YELLOW ry 100% of offspring = _______ genotype
RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy 100% of offspring = _______ genotype _______________________ phenotype ROUND YELLOW
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X R r Y y R r Y y MAKE ANOTHER CROSS HETEROZYGOUS ROUND YELLOW
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POSSIBLE PARENT GAMETES?
RY ry rY Ry
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heterozygous dihybrid 9:3:3:1
RY Ry rY ry ____ Round & Yellow ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green 9 RY Ry rY ry RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy RrYy Rryy rrYy rryy 3 3 1 heterozygous dihybrid Sign of a ______________________ cross is a _____________ ratio in offspring. 9:3:3:1
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__________ratio is a clue that it’s a
9 ____ ____________ TRAIT 1 ; ____________ TRAIT 2 ____ ____________ TRAIT 1; _____________ TRAIT 2 ____ ____________ TRAIT 1; _____________ TRAIT 2 dominant dominant 3 dominant recessive 3 recessive dominant 1 recessive recessive __________ratio is a clue that it’s a ____________________________cross 9:3:3:1 HETEROZYGOUS TWO gene
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PRACTICE MAKING GAMETES for DIHYBRID CROSSES
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What are the possible gametes?
R R T T pure round & pure tall = __________ ____ ____ _____ ______ What gametes can it produce? R T R T R T R T
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What are the possible gametes?
T t R R Heterozygous Tall = __________ & pure round ____ ____ _____ ______ What gametes can it produce? T R t R t R T R
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What are the possible gametes?
T t r r Hybrid tall = __________ & pure wrinkled ____ ____ _____ ______ What gametes can it produce? T r t r t r T r
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What are the possible gametes?
T t R r Heterozygous tall = __________ & hybrid round ____ ____ _____ ______ What gametes can it produce? T R t r t R T r
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