1. Homeroom Warm Up
List the 4 major layers of the Earth from the hottest to the coolest. Also list at least one fact about each layer.

2. Science Warm Up
Scientist theorize that the Atlantic Ocean is slowly increasing in width. Which is the best approximation of the rate at which lithospheric plates beneath the Atlantic Ocean are moving?
2 millimeters per year
2 centimeters per year
2 meters per year
2 kilometers per year

3. Vocabulary Words You should be able to define all of the following words
Genes
Genotype
Phenotype
Chromosome
Inherited Trait
Recessive Trait
Dominant Trait
Heredity
Homozygous
Heterozygous

4. Unit A : Chapter 1 : Section 1
GLEs
GLE Explain the relationship among genes, chromosomes, and inherited traits.
GLE Predict the probable appearance of offspring based on the genetic characteristics of the parents.
Unit A : Chapter 1 : Section 1

5. What is genetics?
The scientific study of heredity

6. Gregor Mendel (1822-1884) The Father of Genetics Mendelian Genetics
2/15/2019
Gregor Mendel ( )
The Father of Genetics
This has been modified from the original ppt Oct. 2011
copyright cmassengale

7. Gregor Johann Mendel Austrian monk
Mendelian Genetics
2/15/2019
Gregor Johann Mendel
Austrian monk
Studied the inheritance of traits in pea plants
Developed the laws of inheritance
Mendel's work was not recognized until the turn of the 20th century

8. copyright cmassengale
Mendelian Genetics
2/15/2019
Gregor Johann Mendel
Between 1856 and 1863, Mendel cultivated and tested thousands of pea plants
He found that the plants' offspring retained traits of the parents
copyright cmassengale

9. Particulate Inheritance
Mendelian Genetics
2/15/2019
Particulate Inheritance
Mendel stated that physical traits are inherited as “particles”
Mendel did not know that the “particles” were actually Chromosomes & DNA
copyright cmassengale

10. copyright cmassengale
Mendelian Genetics
2/15/2019
Why peas?
Can be grown in a small area
Produce lots of offspring
Produce pure plants when allowed to self-pollinate several generations
Can be artificially cross-pollinated
copyright cmassengale

11. Mendel and His Peas Mendel tested 7 traits: Flower color
Flower position
Seed color
Seed shape
Pod shape
Pod color
Plant height

12. Mendel and His Peas
Mendel crossed flowers that were true-breeding for each characteristic.
He crossed a purple (PP) flowered plant with a white (pp) flowered plant. (Parent Generation)

13. Mendel and His Peas
Purple Parent (PP)
The first generation (F1) of plants all had purple flowers.
Where did the white color go??
White Parent (pp)
  (Pp)   
(Pp)
   (Pp)

14. Mendel and His Peas
Mendel took two of his first generation (F1 x F1) purple flowered plants and crossed them together.
In the second generation (F2) he had 3 purple flowered plants, and 1 white flowered plant.
Purple Parent (Pp)
Purple Parent (Pp)   
(PP)
  (Pp)
  (Pp)
  (pp)

15. Mendel and His Peas
Mendel noticed in the first generation, all of the white flowers seemed to disappear.
He called this a recessive trait.
The white color faded into the background at first.
It showed up in the next generation when he pollinated the flowers.

16. Mendel and His Peas
The color (purple) that seemed to mask over the recessive color was named the dominant trait.

17. Mendel and His Peas
Mendel was responsible for figuring out that each plant carried two sets of instructions for each characteristic (one from the “mom” and one from the “dad”).
Like many scientists, his work was not accepted until after his death.

18. Let’s Review
1. If you crossed a true-breeding black rabbit with a true-breeding white rabbit, all of the offspring would be black. Which trait is dominant in rabbits: black fur or white fur?
2. Which trait is recessive?

19. Answer
Black Rabbit (BB)
The trait for black fur is dominant over the trait for white fur. The white fur trait is recessive.
White Rabbit (bb)
  (Bb)
(Bb)

20. Mendel and His Peas Vocabulary
Heredity- the passing of traits from parent to offspring.
2. Dominant trait- the trait observed when at least one dominant allele for a characteristic is inherited
3. Recessive trait- a trait that is apparent only when two recessive alleles for the same characteristic are inherited

21. Mendel and His Peas
4. Genes- a segment of DNA that carries hereditary instructions and is passed from parent to offspring. Genes are located on chromosomes.
5. Alleles- multiple forms of the same gene
6. Genotype- an organisms inherited combination of alleles
7. Phenotype- an organisms inherited appearance

22. Probability The likelihood of a particular event occurring. Chance
Can be expressed as a fraction or a percent.
Example: coin flip.

23. Punnett Square Developed by Reginald Punnett.
A diagram used to show the probability or chances of a certain trait being passed from one generation to another.

24. Reading Punnett squares
Gametes are placed above and to the left of the square
Offspring are placed in the square.
Capital letters (Y) represent dominant alleles.
Lower case letters (y) represent recessive alleles.

25. genotypes
Homozygous = when an organism possesses two identical alleles. ex.
YY or yy
Heterozygous = when an organism possesses different alleles. ex. Yy

26. Phenotype vs genotype Genotype The genetic makeup
Symbolized with letters
Tt or TT
Phenotype
Physical appearance of the organism
Expression of the trait
Short, tall, yellow, smooth, etc.

27. Punnett square example

28. Unit A : Chapter 1 : Section 1
More Practice
Unit A : Chapter 1 : Section 1

29. Punnett square review:

30. Science Closure
The image shows a chromosome. What is located on the chromosome?
A cells
B genes
C enzymes
D organelles

31. Unit A : Chapter 1 : Section 1
Science Closure
In a certain breed of dog, short hair (H) is dominant to long hair (h). A short-haired dog (Hh) is crossed with a long-haired dog (hh). A Punnett square of this cross is shown below. What is the probability that one of the puppies produced by these parents will have short hair? A. 0% B. 25% C. 50% D.100%
Unit A : Chapter 1 : Section 1