Presentation is loading. Please wait.

Presentation is loading. Please wait.

Objective: The student will be able to understand genetics

Similar presentations


Presentation on theme: "Objective: The student will be able to understand genetics"— Presentation transcript:

1 Objective: The student will be able to understand genetics
Pg.

2 Warm up 100% water 0% starch 5% starch 95 % water
Water moves from high concentration to low concentration so water will move into side A

3 Fill in the pamphlet as we go through the PowerPoint
When we are finished you can glue it into your notebook. To do so place a strip of glue on the top of the back page

4 Introduction to Genetics
Genetics = the study of heredity

5 Gregor Medel The Father of Genetics
carried out important studies of heredity Heredity—the passing on of traits from parents to offspring Born in 1822 Austrian monk Used garden peas in his experiments

6 Trait- a specific characteristic that is controlled by genes
Ex. Eye color, hair color, height

7 Sections of DNA that control your traits
Chromosomes Tightly coiled DNA Contain your genes Genes Sections of DNA that control your traits The original parents, the true-breeding plants, are known as the P1 generation. The offspring of the parent plants are known as the F1 generation. When you cross two F1 plants with each other, their offspring are the F2 generation.

8 Homologous Chromosomes
Chromosomes that are the same size and shape and carry the same genes. You get one from your mother and one from your father that match up. P1 Short pea plant Tall pea plant F1 An organism’s two alleles are located on different copies of a chromosome—one inherited from the female parent and one from the male parent. All tall pea plants F2 3 tall: 1 short

9 Alleles The different forms a gene can take. 2 Types of Alleles:
Represented by letters 2 Types of Alleles: 1. Dominant - Represented by a capital letter (Ex. A) 2. Recessive - Represented by a lower-case letter (Ex. a) When recording the results of crosses, it is customary to use the same letter for different alleles of the same gene. An uppercase letter is used for the dominant allele and a lowercase letter for the recessive allele. The dominant allele is always written first.

10 Genotype The combination of two alleles that represent the genetic make-up of a individual. AA Aa aa

11 3 Types of Genotypes: 1. Homozygous Dominant 2. Heterozygous
2 identical alleles that are capitalized (AA, TT) 2. Heterozygous 2 different alleles (Aa, Tt) 3. Homozygous Recessive 2 identical alleles that are lower-case (aa, tt)

12 Brown Hair Phenotype The observable physical characteristic of an individual that are the result of its genotype. Tall Blue Eyes

13 Principle of Dominance
An organism with a recessive allele for a particular trait will exhibit that form only when the dominant allele for the trait is not present. Organisms with a heterozygous genotype (Aa) will never exhibit the recessive trait because it is hidden (masked) by a dominant allele. Punnett Squares: Are used to predict and compare the genetic variations that will result from a cross. The types of gametes go on the top and left sides of the square The possible gene combinations appear in the four boxes If you know the genotypes of the parents, you can use a Punnett square to predict the possible genotypes of their offspring.

14 You try this one: A a

15 Question 1 The passing on of characteristics from parents to offspring is __________. A. genetics B. heredity C. pollination D. allelic frequency Section 1 Check

16 The answer is B. Genetics is the branch of biology that studies heredity.

17 Question 2 Answer What are traits?
Traits are characteristics that are inherited. Height, hair color and eye color are examples of traits in humans. Section 1 Check

18 Question 3 Gametes are __________. A. male sex cells
B. female sex cells C. both male and female sex cells D. fertilized cells that develop into adult organisms Section 1 Check

19 The answer is C. Organisms that reproduce sexually produce male and female sex cells, called gametes. Section 1 Check

20 Question 4 Which of the following genotypes represents a animal that is homozygous dominant for a trait? a. KK b. Kk c. kk Section 1 Check

21 Question 5 Which of the following genotypes represents a plant that is homozygous recessive for height? A. TT B. Tt C. tt Section 1 Check


Download ppt "Objective: The student will be able to understand genetics"

Similar presentations


Ads by Google