Do Now separate sheet of paper 1. What are the two steps in Protein synthesis? 2. How is Transcription different form DNA replication? 3. How is the mRNA strand read to make protein? 4. Transcribe and translate the following DNA: TAC GCT ACT 5. Why is the sequence of nucleotides so important? 6. How does Protein synthesis result in the expression of our genes? Do Now separate sheet of paper Where does Transcription occur? Where does translation occur? What is the monomer of a DNA and RNA? What is the monomer of a protein? Big goal?
EQ: How are genes responsible for the variety of organisms that exist? Mendel Genetics EQ: How are genes responsible for the variety of organisms that exist?
Think-pair-share talk with your partner about why these puppies look different. Hypothesize why some look similar to the mom and some look different?
Understanding Genetics Genetics – study of heredity and variations of inherited characteristics Gene- Piece of DNA that provides instructions for making protein
Understanding Genetics Inheritance- how characteristic and genes are passed from parent to child Heredity- the passing of traits from parent to offspring through genetics
Understanding Genetics Genotype Phenotype The genetic makeup of a specific set of genes Represented with letters An organism’s physical characteristics Can have same phenotype but DIFFERENT genotype
Types of Alleles Dominant Allele Recessive Allele Stronger of the two alleles Will always be expressed if present- only needs 1 copy Capital letter Expressed only when two copies of the allele are present Lowercase letter
Allele Any of the alternative forms of a gene; two alleles for each gene (one on each homologous chromosome) Each letter in the genotype represents one allele Two Types: Dominant & Recessive Combinations: Homozygous Dominant, Homozygous Recessive, Heterozygous Each parent passes one copy of each trait to their offspring
Homo = Same Homozygous Describes two of the same alleles at the same locus (point) 2 dominant alleles (HH) is homozygous Dominant 2 recessive alleles (hh) is homozygous recessive
Heterozygous Hetero = different Describes two different alleles at the same locus (point) (Hh) Carrier: a heterozygous individual who has one recessive allele; doesn’t have the disease, but can pass the recessive allele to offspring
P.S. - use appropriate scientific terminology, always! allele combinations Heterozygous (Hh) Homozygous Dom. (HH) Homozygous Rec (hh) Heterozygous Homozygous dominant Homozygous recessive Based on what you know about allele combinations, describe the genotype of each pair of homologous chromosomes above. P.S. - use appropriate scientific terminology, always!
Check for Understanding Determine whether the following is a genotype of a phenotype: Brown Hair PHENOTYPE
Check for Understanding Determine whether the following is a genotype of a phenotype: An individual has recessive alleles for a gene GENTOTYPE
Check for Understanding A particular allele codes for the shape of a pea. The letter “r” is used to represent this allele. The dominant form is a round form, the recessive form is wrinkled: What is the genotype of homozygous dominant? RR
Check for Understanding A particular allele codes for the shape of a pea. The letter “r” is used to represent this allele. The dominant form is a round form, the recessive form is wrinkled: What is the phenotype of homozygous dominant? ROUND
Check for Understanding A particular allele codes for the shape of a pea. The letter “r” is used to represent this allele. The dominant form is a round form, the recessive form is wrinkled: What is the genotype of homozygous recessive? rr
Check for Understanding A particular allele codes for the shape of a pea. The letter “r” is used to represent this allele. The dominant form is a round form, the recessive form is wrinkled: What is the phenotype of homozygous recessive? Wrinkled
Check for Understanding A particular allele codes for the shape of a pea. The letter “r” is used to represent this allele. The dominant form is a round form, the recessive form is wrinkled: What is the genotype of heterozygous dominant? Rr
What did Gregor Mendel say when he founded genetics? Father of Genetics Studied patterns of inheritance using pea plants Developed three laws of inheritance Law of Dominance Law of segregation Law of Independent assortment What did Gregor Mendel say when he founded genetics? Woo-pea!
Mendel’s law of Dominance When a dominant and a recessive allele are present (Hh) in an organism’s genotype, the dominant allele will mask the recessive allele in the phenotype. Dominant trait will always show if present
Mendel’s law of segregation During the production of gametes, two copies of each gene (allele) separate so that offspring acquire one allele from each parent. Recall: what process produces gametes?
Law of Independent Assortment Inheritance of one trait does not influence the inheritance of a second trait Traits are inherited independently
How can two yellow peas form from green peas?
Punnett squares A tool used to predict inheritance Parents genotypes are on the outside possible genotypes of offspring inside the grid box
Analyzing inheritance Monohybrid cross- Examines the inheritance of one specific trait
Punnett squares r r R Rr Rr R Rr Rr We will use R for the dominant allele (red color) and r for the recessive allele (white color). Identify the alleles that make up the genotype of each parent. Plant 1 = RR, Plant 2 = rr Then separate and distribute them along the top and left side of the square. (Law of Segregation) Complete the cross by placing two alleles in each box based on the outsides of the box r r R Rr Rr R Rr Rr
Offspring possibilities What are the possible genotypes? All heterozygous (Rr). What are the possible phenotypes? All red flowers. Ratio? Pheno Dom: Rec ( 4:0 ) Geno Homo dom: Hetero: Homo Rec 0:4:0
Inheritance practice- minion genetics C – level 2 voice H- ask three before me A- work on creating your minion based on the possible genetics M- remain seated at your table P – complete your own minion genetics Success!
EXIT Ticket Using the terms and ideas you learned today, justify how it is possible for two parents with straight hair (dom.) to have a child with curly hair (recessive)