1. MENDEL’S WORK WEEK 5 NOTES
CH. 3, SECTION 1
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2. I. MENDEL’S WORK
a. __HEREDITY__ is the __PASSING__ of physical caharacteristics from __PARENTS__ to __OFFSPRING__ b. __DIFFERENT__ form of a __CHARACTERICSTIC__, such as stem height or seed color, is called a __TRAIT__. c. __GENETICS__ is the scientific study of __HEREDITY__ d. __HEREDITY__ is the __PASSING__ of physical caharacteristics from __PARENTS__ to __OFFSPRING__

3. 1. MENDEL’S EXPERIMENTS a. __Mendel__ worked with __PEA PLANTS__
b. A __NEW__ organism begins to form when __EGG__ and __SPERM__ join in a process called __FERTILIZATION__
c. __POLLEN__ reaching the __PISTIL__ is called __POLLINATION__
Brain Pop: Heredity (2:28)

4. A. Crossing Pea Plants
a. A __PUREBRED__ organism is the offspring of many __GENERATIONS__ that have the same __TRAIT__
b. Purebred __TALL__ plants will __ONLY__ have __TALL__ offspring

5. B. The F1 Offspring C. The F2 Offspring
a. __PARENT__ plants are known as the __PARENTAL GENERATION__, or __P__ generation
b. The offspring from this cross are the first __FILIAL__ generation, or the __F1__ generation
c. __FILIAL__ comes for the latin work for __DAUGHTERS__ or son
a. __F2__ offspring are a __MIX__ of the __P__ and __F1__ generation

6. D. Experiments with Other Traits
a. Only 1 form of the __TRAIT__ appeared in the __F1__ generation.
b. In the __F2__ generations the __LOST__ form of the __TRAIT__ always reappeared.

7. 2. DOMINANT AND RECESSIVE ALLELES
a. Individual factors, or __SETS__ of genetic information __CONTROL__ the inheritance of __TRAITS__
b. The __FACTORS__ that control each __TRAIT__ exist in __PAIRS__
c. __ONE__ factor comes from __FEMALE__ parent and the __OTHER__ factor comes from the __MALE__ parent
d. One __FACTOR__ in a pair can __MASK__, or __HIDE__, the __OTHER__ factor

8. A. Genes and Alleles
a. __GENE__ is the work for the __FACTORS__ that __CONTROL__ a trait.
b. __ALLELES__ are the __DIFFERENT__ forms of genes
c. __2__ alleles from the __PARENTS__ - __ONE__ from the __EGG__ and the other from the __SPERM__

9. Genes and Alleles Cont.
d. An __ORGANISM”S__ traits are __CONTROLLED__ by the __ALLELES__ in inherits from its __PARENTS__. Some alleles are __DOMINANT__, while other __ALLELES__ are __RECESSIVE__.
e. A __DOMINANT__ allele is one whose __TRAIT__ always shows up in the organism when the allele is __PRESENT__.
f. A __RECESSIVE__ allele is __HIDDEN__ whenever the __DOMINANT__ allele is present.
g. A __RECESSIVE__ allele will __ONLY__ show up if the organism does __NOT__ have the dominant allele
BrainPop Genetics (3:04)

10. B. Alleles in Mendel’s Crosses
a. A __HYBRID__ organism has __2__ different __ALLELES__ for a trait

11. C. Symbols for Alleles
a. __GENETICISTS__ use __LETTERS__ to represent __ALLELES__
b. A __DOMINANT__ allele is represented with a __CAPITAL__ letter
c. A __RECESSIVE__ allele is represented with a __LOWERCASE__ letter

12. D. Significance of Mendel’s Contribution
a. __BEFORE__ Mendel the idea was a __BLEND__ of each parent, so __TALL__ + __SHORT__ = __MEDIUM__
b. Instead, __TRAITS__ are determined by __INDIVIDUAL__ separate __ALLELES__ inherited from each __PARENT__
c. Mendel is often called the __FATHER__ of __GENETICS__
100 Greatest Discoveries:
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