1. Chapter 8 - Heredity

2. Heredity – is the passing of traits from parent to offspring. We call these “inherited traits”.

3. Inherited Traits Living things inherit many traits, or characteristics from their parents. Recall that _________, determine the inherited traits of an organism. Traits are determined by the genes you receive from your parents.

4. Genotype vs. Phenotype Genotype – “genetic makeup” of an organism. Phenotype –– the way an organism looks and behaves as a result of its genotype ---- “physical makeup”. Genotype DETERMINES phenotype

5. Chromosomes Genes are located on structures called chromosomes. Cells of different kinds of organisms contain a different number of chromosomes. A human baby receives ______ chromosomes from its mother, and ______ from its father. Human body cells contain _______ chromosomes.

6. Each pair of chromosomes are given a number from 1 to 23. Genes that determine a specific trait are in matching locations on paired ---“homologous” chromosomes.

7. Check List 1) _________ is the passing on of traits from parents to offspring. 2) A trait is contained in a ___________? 3) What is the difference in genotype and phenotype? 4) How many chromosomes are in the human body cell? How many from dad and mom? 5) What are homologous chromosomes?

8. Traits are controlled by a single gene. An example of a gene is one that causes earlobes to be attached to the head & another form that causes earlobes to be free from the head.

9. Allele – different forms of a trait that make up a gene pair. – “alternate forms of the same gene” Alleles may be either dominant or recessive for a particular trait.

10. Dominant vs Recessive Alleles Dominant allele – is one that is expressed when two different alleles are inherited. Recessive allele – is not expressed unless an organism inherits two copies of it.

11. Identifying Genotype and Phenotype Each pair of genes is part of an individual’s genotype (Ff, Bb, Gg, etc) Genotype identifies which alleles have been passed on to an organism. Capital letter – dominant Lowercase letter – recessive

12. Offspring receive two copies of each gene – one from each parent. 3 possible genotypes: FF, Ff, ff. Homozygous genotype - is made up of two dominant or two recessive alleles “the same” – Ex: FF or ff Heterozygous genotype - is made up of one dominant and one recessive allele “not the same” – Ex: Ff

13. Punnett Square Punnett Square – is a tool used to predict the results when two organisms mate. Used to calculate the probability of genotypes and phenotypes in offspring.

15. Check List 1) What is the passing on of traits from parent to offspring called? 2) What is an organism’s genotype? 3)An organism’s expressed traits make up its ____________? 4) How many total chromosomes are their in a human cell? How many pairs? 5) _________ is two different forms of the same gene. 6) An allele can be either ______________ or ___________?

16. Father of Genetics Gregor Mendel – is considered the “father” of genetics. First experimented with pea plants in 1856. He was a Austrian monk who was fascinated with crossbreeding plants. First to develop punnett square to predict probabilities.

17. Advances in Genetics Genetic Engineering – where scientist alter the DNA of an organism to benefit. 3 advantages of genetic engineering: – 1) Gene transfer ( out with the bad in with the good ) – 2) Genetically engineered plants – 3) Genetically engineered animals

18. Chapter 8 - Heredity

19. Heredity - ____________________________ ____________ are passed on to future generations

20. Inherited Traits Recall that _________, determine the traits of an organism. Traits are determined by the genes you receive from your parents.

21. Genotype – _____________________________________ _____________________________________ Phenotype – _____________________________________ _____________________________________ Genotype DETERMINES phenotype

22. Chromosomes 23 pairs of chromosomes in each cell = __________ total Each pair has a chromosome from a mom and a dad. On each chromosome is an alternating ___________.

23. Chapter 8 Check List 1) _____________ -is the process of passing traits from parents to offspring. 2) The genetic makeup or genes of an organism is called its _________________. 3) _________ determines the inherited traits of an organism. 4) ______________ - is the way an organism looks and behaves –“expressed or physical makeup” 5) More complex organisms generally contain ________ chromosomes. 6) Genes code for certain _____________. 7) Inherited traits means we get our characteristics from our ______________. If we have 2 parents, there is ______________ in the offspring. 8) Above in #7, what type of reproduction has been involved?

24. Section 2

25. Chromosomes Genes are located on structures called chromosomes. Cells of different kinds of organisms contain a different number of chromosomes.

26. Traits are controlled by a single gene. An example of a gene is one that causes earlobes to be attached to the head & another form that causes earlobes to be free from the head.

27. Allele - _____________________________________ Alleles can be either _______________ or _______________.

28. Dominant Allele - _____________________________________ Recessive Allele - _____________________________________

30. Each pair of genes is part of an organism’s _________________. (ex: Ff, Dd, Tt) Genotype shows which alleles have been passed on. Capital Letter = ___________ allele Lowercase Letter = _________ allele

31. Offspring receive two copies of each gene – one from each parent. 3 possible genotypes:_______, _______, ______ Homozygous genotype - ______________________________________ – Ex: Heterozygous genotype - _______________________________________ – Ex:

32. Section 3 Genotype vs Phenotype Tt vs Tall Homozygous vs Heterozygous Dominant vs. Recessive 3 genotypes

33. Punnett Square Punnett Square – ______________________ ______________. Used to calculate the _________ of genotypes and phenotypes in offspring.

35. Task 1 Draw a punnett square when a heterozygous parent for tallness mates with a homozygous parent for shortness. ( use T and t ).

36. Task 2 Draw out a punnett square for two organisms that mate: one is Heterozygous for being athletic, and the other is homozygous recessive for being athletic (Use A or a)

37. Task 3 A male eastern fox squirrel is notorious for mating in the winter months and for finding a mate who is always homozygous dominant. If a male eastern fox squirrel is homozygous for being slow and finds a mate draw a punnett square (F=fast; f=slow) and predict these: – What is the probability of the offspring being fast? – What is the probability of the offspring being slow? – What % will be homozygous? – What % will be heterozygous?

38. Section 3 cont.

39. Father of Genetics Gregor Mendel – ______________________. First experimented with pea plants in 1856. Used the ___________________ in his studies.

40. Advances in Genetics Genetic Engineering – _____________________________________ ______________________. 2 advantages of genetic engineering: – 1) – 2)