Section 6-4 “Traits & Genes” Write everything that is underlined

KEY CONCEPT Genes encode proteins that produce a diverse range of traits

Important Vocabulary Terms for You to Know Please make a chart or table at the top of your notes for these vocabulary terms: Gene Allelle Homozygous Heterozygous Genome Genotype Phenotype Dominant Recessive

A. The same gene can have many versions 1. A gene is a piece of DNA that tells a cell to make a certain protein Each gene has a locus, a specific position on a pair of homologous chromosomes

2. An allele is an alternative form of a gene -Each parent donates one allele for every gene Pea plants have 2 alleles for shape - they receive one from each parent For shape, there is a wrinkled allele and a round allele

B. Genes influence the development of traits All of an organism’s genetic material is called the genome A genotype refers to the actual genes A phenotype is the physical expression of a trait

C. Genotype: 1. The gene combination of an organism It consists of 2 alleles For example: Pure dominant, 2 dominant genes Pure recessive, 2 recessive genes Hybrid, 1 dominant and 1 recessive gene

1. The way an organism looks D. Phenotype: 1. The way an organism looks No matter what genes are present, phenotype of a tall pea plant is tall and a short pea plant is short

2. Dominant alleles are represented by uppercase letters A dominant allele is expressed as a phenotype when at least one allele is dominant A recessive allele is expressed as a phenotype only when two copies are present 2. Dominant alleles are represented by uppercase letters 3. Recessive alleles by lowercase letters

Think fast!!! Determine if the following is genotype or phenotype. A horse with white stockings A pink rose that was bred from a white rose and red rose A pig that has super heavy muscling

E. Mendel’s observed traits Dominant traits: covers up the other traits Recessive traits: traits that “disappear” Rule of Dominance: When a dominant trait is present the recessive trait is hidden

How’s it related???? You have 4 minutes and 25 seconds to draw a concept map to show (with words, chart, or a concept map) how these terms are related. Gene Genotype Phenotype Allelle Dominant traits Recessive traits

Most traits occur in a range and do not follow simple dominant-recessive patterns

F. The Law of Independent Assortment: Genes for different traits are inherited independently of each other When you have 2 or more different traits they are not “stuck” together

Example (for your genetics book) Seed types of Parents: Wrinkled, yellow Round, green You can get offspring with: Wrinkled, green seeds Or Round, yellow seeds