1. Heredity Chapter 11

2. Transmission of characteristics from parent to offspring is called ___________________.
The science that studies how those
characteristics are passed on from one
generation to the next is called
___________________
heredity
Genetics

3. The Father of Genetics _________________ -a monk
-studied traits in pea plants the beginning of our understanding about how genes work
Gregor Mendel

4. Mendel experimented
using ___________
_______ part of flower makes
________
__________ part of flower makes
_______ cells
Pea plants
MALE
Pollen
FEMALE
egg

5. Pea plants are normally self-pollinating so seeds have one parent

6. 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

7. P1 generation (_________) generation
MENDEL’S EXPERIMENTS
P1 generation (_________)
generation
parental F1 F2

8. When Mendel crossed PLANTS with 2 contrasting traits: (EX: Tall crossed with short)
He always found same pattern:
1. ONLY one trait showed in the F1 generation BUT . . .
2. Missing trait returned in
the F2 generation
in a 3:1 ratio

10. Two Conclusions….
1) Must be a pair of factors controlling a trait…one can hide the other

11. The factors are GENES carried on the pair of homologous chromosomes
Different gene choices
for a trait are called
alleles

12. 2nd Conclusion…
The Principle of dominance Some alleles are dominant and others are recessive

13. 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

14. DOMINANT/RECESSIVE T t (not s for short) capital Dominant Recessive
_____________ 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)

15. HOMOZYGOUS HETEROZYGOUS
When both alleles in the pair are the same, the organism is _______________ or __________
EX: ____ or ___
When both alleles in the pair are different, the organism is
_________________ or _____________
Ex: ____
HOMOZYGOUS PURE
TT tt
HETEROZYGOUS HYBRID Tt

16. PHENOTYPE/GENOTYPE
The ________________ of an organism is its _____________
The ____________of an organism is
its _____________
genetic makeup
GENOTYPE
appearance
PHENOTYPE

17. 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

18. REMEMBER SEGREGATION _____________ chromosomes ________________ during
ANAPHASE I
= _________________
HOMOLOGOUS
SEPARATE
SEGREGATION

19. 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 _____________
TALL
SHORT
LOOK TALL
carrying
shortness

20. make 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
make gametes
recessive
reappears

21. MAKING A CROSS for only a __________ trait = ____________________
ONE GENE
MONOHYBRID CROSS

22. DIHYBRID CROSSES
(2 traits)

23. MAKING A CROSS with ___________________= ____________________
TWO gene traits
DIHYBRID CROSS

24. LAW OF __________________________
the factors are distributed to gametes independently of other factors
INDEPENDENT ASSORTMENT