genetic vocabulary
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- Perform polyhybrid cross for incomplete dominance
- Perform Polyhybrid cross for incomplete dominance
- Heterozygous
- When alleles are NOT the same in the organism Ex: Tt
- What is codominance?
- No truly dominant allele, rather than blending of two phenotypes, both phenotypes of the dominant alleles are expressed Ex: White chicken and black rooster gives black and white offspring Not grey
- Allele
- a factor that controls traits in pairs
- Dominant allele
- Always shows up in an organism when it is present
- Probability
- A number that describes how likely it is that an event will occur Ex; flip a coin what is the probability that it will land on heads (or tails)
- Explain codominance with two alleles.
- No truly dominant allele, rather than blending of two phenotypes, both phenotypes of the dominant alleles are expressed Ex: White chicken and black rooster gives black and white offspring Not grey
- What are sex-linked traits?
- The last pair of chromosomes are ones coded for gender and other sex-linked traits like color blindness, baldness, hemophilia
- How does polygenic inheritance change the phenotypic expression of genes?
- Many variations of the gene expression - Skin color lt brown, very white, brown
- What is a dihybrid cross?
- A punnet square that uses more than just 2 traits.
- Describe the first cross he did.
- Purebred tall pea plant with a purebred short pea plant - all offspring were tall
- Homozygous
- Both alleles are the same in an organism Ex: TT or tt
- Punnett Square
- Use this to predict probability of offspring
- Purebred/pure breeding
- Organisms that always produce the same traits generation to generation Ex: A tall offspring is purebred for the tall trait
- heredity
- The passing of traits (physical characteristics) from parents to offspring
- Perform Monohybrid cross for incomplete dominance
- Perform Monohybrid cross for incomplete dominance
- Be able to do monohybrid crosses for both types of codominance
- Show Monohybrid cross for codominance with 2 alleles and with multiple alleles
- Examples of traits that are passed through polygenic inheritance
- Ex: Skin color, Eye color, Ht, Wt
- Explain the difference of codominance with 2 alleles vs codominance with multiple alleles
- Codominance with 2 alleles is black and white (not grey) Codominance with multiple alleles is more than 2 alleles for a trait Ex: Blood type - A allele (Dominant), B allele (Diminant), or O allele (recessive)
- Genes
- traits inherited through the actions of alleles Genes are found on chromosomes
- Know how to do monohybrid and polyhybrid crosses for sex-linked traits
- Know how Monohybrid and polyhybrid corsses for sex-linked traits
- Perform Dihybrid crosses with complete dominance
- Show dihybrid cross with complete dominance
- Phenotype
- What the physical expression of the gene will be Ex: TT and Tt: the phenotype is TALL tt: the phenotype is short
- If a trait is X-linked and recesssive, why does it appear more often in males than in females?
- Because the X chromosome is longer than any trait on that piece, the sex-linked trait will be expressed in males more frequently
- Perform simple monohybrid crosses where the organisms show complete dominance using a Punnet Square
- Perform Monohybrid cross with complete dominance (Use punnet square)
- Why are they used?
- Used to determine two factors of an offspring
- What happened to the next generation
- Resulting offspring were 75% tall and 25% short
- Be able to do polyhybrid crosses for both types of codominance
- Show Polyhybrid cross for codominance with 2 alleles and with multiple alleles
- What is polygenic inheritance?
- Many traits are not controlled by a single gene, many genes working together to cause the expression of the gene, resulting in variations of the gene expression Ex: Skin color, Eye color, Ht, Wt
- Genotype
- Describes what the alleles of the offspring will be Ex: Tt or TT or tt
- traits
- physical characteristics controlled by genes
- Genetics
- The study of how traits are inherited through the action of alleles
- Recessive allele
- Hidden when the dominant is present (to show the recessive allele the organism must be homozygous recessive for that trait
- What was he doing his work on?
- Pea Plant traits
- First Geneticist
- Gregor Mendel - research between 1856 and 1866
- Explain what is happening with incomplete dominance
- The phenotype of the heterozygote will be intermediate between the phenotypes of the two homozygotes. Ex: Red flowers show incomplete dominance to White = Pink