11-1 The Work of Gregor Mendel

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11-1 The Work of Gregor Mendel

• Atwater Agriculture Department

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11-1 Vocabulary

• Genetics
• the scientific study of heredity
• You get your genetics from your ______. _____,
  _____, and ______ are examples of genetics.

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ThinkPair Share

1. What are genetics?
2. Where do you get your genetics from?

We get our genetics from ________.
Genetics are _______.

• Together, explain what a genetics are.

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• True-breeding-
• term used to describe organisms that produce
  offspring identical to themselves if allowed to
  self-pollinate
• True-breeding happens in _____ when they
  self-pollinate.

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ThinkPair Share

1. What is true breeding?
2. What is an example of true breeding?

An example of true breeding is ________.
True breeding is _______.

• Together, explain what true breeding is.

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• Trait-
• specific characteristic that varies from one
  individual to another
• _________ would be a trait that your parents gave
  you.

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ThinkPair Share
Sentence for Trait Give one example
Definition for Trait Give one example

• Together, explain what a trait is and give an
  example.

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11-1 Vocabulary

• Hybrid-
• offspring of crosses between parents with
  different traits
• A ________ is an example of a hybrid because
  _________.

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• Gene-
• sequence of DNA that codes for protein and thus
  determines a trait
• A gene codes for traits such as ______, ______,
  _______ and _______.

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• Allele-
• one of a number of different forms of a gene
• An allele is a part of the chromosome

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ThinkPair Share

1. What is an allele?
2. Where are alleles located at?

An allele can be found ________.
An allele is _______.

• Together, explain what an allele is.

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11-1 Vocabulary
Allele
Allele

• Segregation-
• separation of alleles during gamete formation
• Segregation means _____________.

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ThinkPair Share

• When does segregation happen?

Segregation happens_____________.

• Together, explain what segregation is.

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• Gamete-
• specialized cell involved in sexual reproduction
• Gamete is another word for _______ or _________
  cells.

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11-1 Notes

• 1. Genes and Dominance
• a. Mendel studied different traits with
  contrasting characteristics
• b. Traits- a specific characteristic such as seed
  color or plant height that varies from one
  individual to another.
• c. Hybrids- Offspring of parent crosses with
  different traits
• d. Genes- chemical factors that determine traits
  (height)
• Alleles- different forms of a gene (short or tall)

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11-1 Notes

• f. Principle of dominance Alleles can be
  dominant or recessive
• i. Dominant trait is always seen
• Ii. Recessive trait is seen if dominant is not
  present

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ThinkPair Share

1. What does Dominant mean?
2. What does recessive mean?

Dominant means_____
Recessive means ________.

• Together, compare and contrast dominant and
  recessive traits.

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11-1 Notes

• 2. Explaining the F1 Cross
• a. Segregation- separation of alleles
• Gametes- sex cells (during formation plant
  alleles were segregated)
• Law of Segregation Alleles for each trait are
  randomly separated during formation of sex cells
  (gametes)

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Principles of Dominance
Section 11-1
P Generation
F1 Generation
F2 Generation
Tall
Short
Tall
Tall
Tall
Tall
Tall
Short
Go to Section
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Principles of Dominance
Section 11-1
P Generation
F1 Generation
F2 Generation
Tall
Short
Tall
Tall
Tall
Tall
Tall
Short
Go to Section
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Principles of Dominance
Section 11-1
P Generation
F1 Generation
F2 Generation
Tall
Short
Tall
Tall
Tall
Tall
Tall
Short
Go to Section
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Figure 11-3 Mendels Seven F1 Crosses on Pea
Plants
Section 11-1
Seed Shape
Flower Position
Seed Coat Color
Seed Color
Pod Color
Plant Height
Pod Shape
Round
Yellow
Gray
Smooth
Green
Axial
Tall
Wrinkled
Green
White
Constricted
Yellow
Terminal
Short
Round
Yellow
Gray
Smooth
Green
Axial
Tall
Go to Section
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11-1 Review

• What are dominant and recessive alleles?
• Dominant allele allele whose from of a trait
  always show up in an organism if the dominant
  allele is present
• Recessive allele allele whose form of a trait
  shows up only when the dominant allele is not
  present.

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11-1 Review

• What is segregation? What happens to alleles
  during segregation?
• Separation of paired alleles the alleles are
  separated during the formation of gametes, with
  the result that each gamete carries only a single
  allele from the original pair.
• What did Mendel conclude determines biological
  inheritance?
• Factors that are passed from one generation to
  the next.

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11-1 Review

• Describe how Mendel cross pollinated pea plants..
• Mendel cut away the male parts of one flower,
  then dusted it with pollen from another flower.
• Why were true-breeding pea plants important for
  Mendels experiments?
• True-breeding pea plants have two identical
  alleles for a gene, so in a genetic cross each
  parent contributed only one from of a gene,
  making inheritance patterns more detectable