1. Title: Biology 1/26/07 Objectives: Class Topics
2/19/2019
Title: Biology 1/26/07
Objectives:
To assess learning about genetic variation due to meiosis and about gametogenesis.
Class Topics
Hand in W.S. 8.1 before the bell rings please
Review Chapter 7 Test
Chapter 8 – Mendelian Genetics
Terms
Mendel’s research
Mendel’s laws
"It has become fashionable in science education to mold K-12 students around an idee fixe of a modern scientist; formulating hypotheses, observing measuring, and discovering through hands-on investigations. What has been left unsaid is that real scientists don't actually spend very much of their day 'observing' and 'measuring.' They read! Reading for understanding of content is the core process skill of science, and there is no substitute for practice at an early age Dr. Stan Metzenberg, "Reading: The Most Important Science Process Skill"
Tuesday, February 19, :29 AM

2. Class Assignments Read 161-165 1/26/07 W.S. 8.1 (DR/Quiz) 1/26/07
2/19/2019
Class Assignments
What
By When
Read /26/07
W.S. 8.1 (DR/Quiz) 1/26/07
Read /30/07
W.S. “The Puzzle of Heredity” 1/30/07
Due this class period
Due next class period
Due in the future

3. 2/19/2019
Grade Sheet
2A – p. 157 (5 pts.)

4. Chapter 7 Test Review Absolutely no talking
2/19/2019
Chapter 7 Test Review
Absolutely no talking
You have 7 minutes to review your exam – do not write anything on the test
You will get your test back next class period and be given 20 minutes to adjust any answers.
I suggest you make notes
of items to study
of questions to ask

5. Mendel’s Breeding experiments 8.1
2/19/2019
Mendel’s Breeding experiments 8.1
Gregor Johann Mendel’s history
“Father” of genetics
Bred garden peas (Pisum sativum)
1st to develop rules to predict patterns in inheritance of traits
Quantitative Data!!!!
Used very large samples
Kept careful records
Minimized errors (took time and stayed organized)

6. Key Terms I 7.1 Heredity Genetics Gene Cross
2/19/2019
Key Terms I 7.1
Heredity
Passing traits from parents to offspring
Genetics
Branch of biology that studies heredity
Gene
Unit of DNA that controls traits
Cross
Mating or breeding of two individuals

7. Why peas? 8.1 Several traits take clearly different forms
2/19/2019
Why peas? 8.1
Several traits take clearly different forms
Ex. Yellow or green seeds
Male and female parts of peas are enclosed within the same flower
Mating can be controlled as either:
Self fertilization (self-pollination)
Cross-pollination
Mendel removed the stamens (male) from the flower of on plant and dusted the pistil (female) of another
Peas are small, grows quickly, and produces many offspring
Not to mention that the offspring can be used as food!!

8. From : http://www.people.virginia.edu/~rjh9u/monotraits.html
2/19/2019
From :

9. 2/19/2019
Peas have 14 chromosomes (? Pairs) and each gene was on a different chromosome

10. Key Terms II Monohybrid cross True breeding (pure) P generation
2/19/2019
Key Terms II
Monohybrid cross
A cross that involves one pair of contrasting traits
True breeding (pure)
All offspring display the same form of the trait
P generation
1st two individuals (mated or bred)
F1 generation
Offspring of P generation (F means filial)
F2 generation
Offspring of self-pollinated F1 generation

11. Example of a classic Mendel’s cross
2/19/2019
Example of a classic Mendel’s cross
P generation
Tall crossed with dwarf (both purebreeding)
F1 generation
All tall
Self-pollinate a single example of F1
F2 generation
787 tall, 277 dwarf
2.84 : 1 ratio
Close to a 3:1 ratio

12. Math Lab p. 165 “Calculating Mendel’s ratios” Copy the table
2/19/2019
Math Lab p. 165
“Calculating Mendel’s ratios”
Copy the table
Calculate the ratio
State the ratio in words and then as a fraction
Answer the final question

13. 2/19/2019

14. Mendel’s Theory Historical perspective
2/19/2019
Mendel’s Theory
Historical perspective
Heredity was thought of as a blending of the two parents
Mendel determined that there were two separate “heritable factors” for each trait
Factors are called alleles (book says genes)

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16. 2/19/2019
Mendel’s hypothesis
1. For each inherited trait, an individual has two copies of the gene – one from each parent.
2. There are different versions of genes.
Alleles
Receive one from each parent

17. Mendel’s hypothesis 3. Dominant allele recessive allele
2/19/2019
Mendel’s hypothesis
3. Dominant allele
Can mask the presence of another allele
Expressed whenever present
Represented by a capital letter
recessive allele
Can be masked by the presence of a dominant allele
Only expressed when contrasting allele is not present
Represented by a lowercase letter (same letter as dominant)