13) PHENOTYPE: the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.

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1 12) GENOTYPE: the genetic makeup of an organism with reference to a single trait, set of traits, or the entire complex of traits. 13) PHENOTYPE: the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment. Is this the correct phenotype for the genotype shown?

2 12) GENOTYPE: the genetic makeup of an organism with reference to a single trait, set of traits, or the entire complex of traits. (It s the recipe the directions)

3 11a) DOMINANT ALLELE: its trait will win when at least one of the paired alleles is dominant. 11b) RECESSIVE ALLELE: its trait will win only when both paired alleles are recessive

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5 10) ALLELES: variations of genes that determine traits; the two alleles on paired chromosomes constitute a gene.

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7 The walkingsticks had only one feature we investigated color. We started with a population of 48 walkingsticks. The population was composed of equal numbers of thee different traits brown, green-brown, and geen. In addition to the walkingsticks there were birds that preyed on the insects for food. In what way did the population change? What factors in the environment affected the change in the walkingstick population? How did variation help the walkingstick population survive? Was there more or less variation in the walkingstick population after 5 generations?

8 Is there variation in the yammer of larkeys? How might a predator have an impact on the population of larkeys? What trait might disappear from the population after five generations?

9 Inside the nucleus is the inheritance messenger, DNA. (Deoxyribonucleic acid). DNA molecules are huge containing millions of atoms. In order to fit inside the nucleus, they are coiled and coiled again into structures called CHROMOSOMES - the structures that carry the message of inheritance.

10 This drawing shows the nucleus of a cell from our animal, the larkey. Notice that there are eight chromosomes, looking a little bit like bent hot dogs of different lengths. If you look closely, you will see that these two chromosomes are the same, these two are the same, and so on.

11 Chromosomes always come in pairs. So our larkey actually has four pairs of chromosomes rather than eight different ones. Now look at the dark areas. Both chromosomes in a pair have dark areas exactly the same location. The dark areas are called alleles. Note: Alleles are not really dark. The dark color is used to represent the location of the alleles on the chromosomes

12 The two alleles on the paired chromosomes work together. Together they constitute a gene. Summary Nuclei contain chromosomes. Chromosomes come in almost identical pairs. Chromosomes have specific active locations called alleles. The two alleles in identical locations on paired chromosomes constitute a gene

13 A gene (two alleles working together) controls a trait. This gene could be the one that determines the larkey s eye color, or perhaps the pattern of its fur. Let s say it determines eye color. The larkey has four features of interest to us. Each feature is controlled by one gene. Each of the four genes is on a different chromosome (although they could have all been on the same chromosome).

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15 The gene location for appendages (legs) is these two alleles on this pair of chromosomes. The alleles are labeled with the letter A for appendages.

16 Find the gene locations for eye color (letter E), fur pattern (letter F), and tail shape (T). Notice that some of the alleles are labeled with uppercase letter and some are lowercase letters. Both upper and lowercase letter Es are alleles for eye color.

17 Alleles don t all have equal influence in determining traits. Moreinfluential alleles are dominant alleles, and they are represented by an uppercase letter. Less-influential alleles are called recessive alleles, and they are represented by a lowercase letter.

18 The alleles are the code that determines the traits of the larkeys. The chart at the bottom is the genetic code for one of the 32 larkeys we viewed previously. The alleles for legs is aa, eye color = Ee, fur pattern = FF, and tail shape = tt;

19 The alleles for legs is aa, eye color = Ee, fur pattern = FF, and tail shape = tt; The combination of alleles in an organism's chromosomes is the organism s genotype. The genotype lists the paired alleles that are particular to that organism.

20 Let s look at the genotype of our larkey to see what is dominant and what is recessive. Two recessive alleles for leg length (aa) One dominant and one recessive allele for eye color (Ee) Two dominant alleles for fur pattern (FF) Two recessive alleles for tail shape (tt).

21 The parents of a Larkey both have red eyes. Is it possible for them to produce an offspring with grey eyes? In your notebook use a Punnet Square to prove or disprove this grey eye question. (The alleles for eyes are E or e.)

22 Mendel studied pea plant traits such as: flower color, seed color, and tall versus short

23 F1 generation were ALL TALL but not all F2 s were tall!

24 Tt Tt Draw this Punnett square Tt Tt

25 This generation produces plants at a rate of 3 tall for every 1 short.

26 2 3 1

27 1) By conducting careful over many years, Mendel made landmark discoveries in and established a new science:. 2) List three significant variations observed by Mendel regarding the common garden pea Pisum sativum. 3) How did Mendel obtain pure breeding strains of plants for a trait such as plant height? 1) Experiments heredity, genetics. 2) Color of seeds, color of flowers, height of plants. 3) Mendel obtained pure breeding strains for traits such as plant height by using self pollination over several generations.

28 The parents of a Larkey both have red eyes. Is it possible for them to produce an offspring with grey eyes? In your notebook use a Punnet Square to prove or disprove this grey eye question. (The alleles for eyes are E or e.)

29 The parents of a Larkey both have red eyes. Is it possible for them to produce an offspring with grey eyes? In your notebook use a Punnet Square to prove or disprove this grey eye question. (The alleles for eyes are E or e.) Male Ee E Female Ee E E E E e e e E e e e

30 WORD BANK (top) chromosomes (2x) dominant, DNA, genes, genotype, nucleus, paired alleles, phenotype, recessive; WORD BANK (bottom) allele, chromosome, gene, nucleus.

31 Top (in order) nucleus, DNA, chromosomes, chromosomes, genes, paired alleles, genotype, phenotype, dominant, recessive. Bottom (in order) chromosome, gene, nucleus, allele

32 AA Aa AA Aa aa F 1 F 1 F 1 Aa Aa Aa F 2 F 2 F 2 aa aa AA F 3 F 3 F 3

33 AA Aa AA Aa aa F 1 F 1 F 1 Aa Aa Aa F 2 F 2 F 2 aa aa AA F 3 F 3 F 3

34 AA Aa AA Aa aa F 1 F 1 F 1 Aa Aa Aa F 2 F 2 F 2 aa aa AA F 3 F 3 F 3

35 AA Aa AA Aa aa F 1 F 1 F 1 Aa Aa Aa F 2 F 2 F 2 aa aa AA F 3 F 3 F 3

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