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 Explain how genes are responsible for certain traits that we acquire from our parents?  In complete sentences, explain meiosis and explain its role.

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Presentation on theme: " Explain how genes are responsible for certain traits that we acquire from our parents?  In complete sentences, explain meiosis and explain its role."— Presentation transcript:

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2  Explain how genes are responsible for certain traits that we acquire from our parents?  In complete sentences, explain meiosis and explain its role in sexual reproduction. Remember to include heredity.  http://app.discoveryeducation.com/player/vi ew/assetGuid/AC056D43-D1C5-4200-AB9B- E564C7C74009 http://app.discoveryeducation.com/player/vi ew/assetGuid/AC056D43-D1C5-4200-AB9B- E564C7C74009

3  Video Questions:   Q: What do you know about genetics?  Q: What does the term “Mendelian Trait” describe? Q: What do you know about genetic mutations?  Q: What are transposons?  Q: What do you know about DNA and describe the structure of DNA?  Q: How does RNA work?  Q: What do you think will be some future applications of genetics?  Q: What are the possible future applications for RNA interference? 

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5  Austrian monk who studied mathematics and science  As a boy he could predict the possible types of flowers and fruits that would result from crossbreeding two plants in his father’s garden

6  Curiosity about the connection between the color of a pea flower and the type of seed that same plant produced inspired him to begin experimenting with garden peas in 1856.  Made careful use of scientific methods, which resulted in the first recorded study of how traits pass from one generation to the next.

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8 The study of how traits are inherited through the interactions of genes.

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10  The material that controls which traits are expressed in an organism  Genes come in pairs and offspring inherit one copy of each gene from each parent

11  Heredity  Allele  Trait

12 The passing of traits from parent to offspring

13  The different forms of a trait that a gene may have  One form of a gene

14  Ways of looking, thinking, or being  Traits that are genetic are passed down through the genes from parents to offspring

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16  A trait that is covered over, or dominated, by another form of that trait and seems to disappear  Hidden when the other copy of the gene contains the dominant allele.  A recessive allele shows up only when there is no dominant allele present  Shown with a lower-case letter

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18  Both alleles [forms of the gene] are the same  When offspring inherit two dominant genes, (one dominant gene from each parent) they are said to be homozygous dominant  When offspring inherit two recessive genes, (one recessive gene from each parent) they are said to be homozygous recessive

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20  When alleles occur in different forms  When offspring inherit one dominant gene and one recessive gene, they are said to be heterozygous  Since the dominant gene will be expressed, they are said to be heterozygous dominant

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22  When an organism has two different alleles for a gene that does not follow the dominant/recessive pattern  The organism shows a trait that is a blend of the traits represented by the two alleles  Also called INCOMPLETE DOMINANCE

23 For example: The gene for the color of some flowers has one allele for red and one for white. When both alleles are present, neither is dominant, and the flower color is pink

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25  A trait that covers over, or dominates, another form of that trait  Trait that always shows up, even when only one of the two alleles is in the dominant form  Shown by a capital letter

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27 An organism's genetic makeup

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29 Outward physical appearance and behavior of an organism

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31  A tool to predict the probability of certain traits in offspring that shows the different ways alleles can combine  A way to show phenotype & genotype  A chart that shows all the possible combinations of alleles that can result when genes are crossed

32  Letters stand for dominant and recessive alleles  An uppercase letter stands for a dominant allele  Lowercase letters stand for recessive alleles

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34  Now you need two parents to mate, ones with a known genotype  For example, a red flower (genotype Rr) and a white flower (genotype rr). Rr x rr

35  Place one of the parents on top, and one on the left. You should get a something similar to this:

36  The two-letter combinations are the possible genotypes of offspring  They are: Rr, Rr, rr, and rr genotypes  From this it is possible to determine the probability (chance) that a flower will have a red phenotype (2/4 or 50%) or a white phenotype (2/4 or 50%)

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38  Traits are controlled by alleles on chromosomes  An allele’s effect is dominant or recessive  When a pair of chromosomes separate during meiosis the different alleles for a trait move into separate sex cells

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40  A trait that is controlled by more than two alleles is said to be controlled by multiple alleles  Traits controlled by multiple alleles produce more than three phenotypes of that trait

41 For Example: The alleles for blood types in humans are called A, B, and O The O allele is recessive to both the A and B alleles

42 When a person inherits one A allele and one B allele for blood type, both alleles are expressed The person has the blood phenotype AB

43 A person with phenotype A blood inherited an A and an O allele (AO) ~OR~ an A and an A allele (AA)

44 Someone with phenotype B blood has the genotype BB or BO This person inherited either a B and an O allele ~OR~ Two B alleles

45 A person with phenotype O blood has the genotype OO

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47  Occurs when a group of gene pairs acts together to produce a trait  The effects of many alleles produces a wide variety of phenotypes

48  A student notices that fruit flies with curly wings trait develops straight wings if kept at temperature 16 degree Celsius. The best explanantion for this observation is that  (a) wing shaped is controlled by behavior  (b) wing shaped is influenced by light intensity  (c) gene expression can be modified interactions with environment  (d) gene mutations for the wing shape can occur at high temperatures  EXPLAIN WHY YOU CHOOSE YOUR ANSWER.

49 Pick and answer and explain why you chose that answer.

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