Reproduction and Genetics

Two Types of Reproduction _________________- Only one parent and genetic material is identical to parent. __________________- Two parents and offspring receives genes from both parents. Asexual Reproduction Sexual Reproduction

Asexual Reproduction Binary Fission- asexual reproduction that occurs in single celled organisms in which genetic material is copied and one cell divides into two identical daughter cells. EX: Bacteria reproduce this way, and Yeast

Asexual Reproduction Budding- an organism grows a part of of its main body and this new growth eventually breaks off to become a new organism. Ex: Hydra (simple animal similar to jelly fish)

Asexual Reproduction Fragmentation- Fragmentation is a form of asexual reproduction where a new organism grows from a fragment of the parent. Each fragment develops into a mature, fully grown individual. Ex: Starfish, and some fungi.

Sexual Reproduction Sexual Reproduction- Type of reproduction in which male and female reproductive cells combine to form new offspring with genetic material from both parents. ***Offspring has genetic material from each parent which creates- Offspring is NOT identical to parent!

Sexual Reproduction - Variation 23 Chromosomes 46 Chromosomes Male Gamete Female Gamete

Sexual Reproduction - Variation 23 Chromosomes 46 Chromosomes Male Gamete Female Gamete

Asexual ReproductionSexual Reproduction Disadvantages Advantages

Selective Breeding When humans select organisms for breeding to get desirable traits. Breeding chickens that lay the most eggs

1.Gregor Mendel – was an Austrian monk born in 1822 who is known as the “father of genetics” Genetics – the scientific study of heredity Heredity – the passing of traits from parents to offspring a.Traits are inherited by parents passing alleles to their offspring (1 allele from dad & 1 allele from mom) a.Allele= different forms of the same gene (ex: eye color = gene; brown eyes= allele, blue eyes= allele

b. Some alleles are dominant (R) and some are recessive (r) Dominant – will always express its form of a trait when present Recessive – will only express its form of a trait when the dominant allele is not present. Genotypes Homozygous (rr, RR) SAME ALLELES Heterozygous (Rr) – dominant trait always shows. DIFFERENT ALLELES

Remember: DNA is found in the nucleus. It is organized into a chromosome before it is copied. Genes are located on chromosomes!! Sex cells (gametes) are produced by meiosis and have half the number of chromosomes (haploid)

For every Gene or trait, an individual gets ____ alleles 2

Alleles ____________ alleles are represented by a capital letter and are expressed even if one is present in the genotype. (Ex: BB= brown eyes, Bb= brown eyes) ___________ alleles are represented by a lower case letter, and are only expressed if the dominant allele in not present. (Ex: bb= blue eyes) DOMINANT RECESSIVE

Vocabulary ______________is the combination of alleles _______________ is the trait that is expressed BBbbBb Brown eyesBlue Eyes Genotype Phenotype

Give the name of the Genotype If both alleles are dominant (BB), we call this ____________ Homozygous Dominant The phenotype will be _____________________ Brown Eyes If both alleles are recessive (bb), we call this _________________ Homozygous Recessive The phenotype will be ________________Blue Eyes If one allele is dominant and the other is recessive (Bb), we call this __________Heterozygous The phenotype will be _________________ Brown Eyes

Name the Genotype Bb= bb= BB= Heterozygous Homozygous Recessive Homozygous Dominant

Give me the genotype or genotypes possible for the following phenotypes Brown Eyes = Blue Eyes = BB orBb bb

Brown eyes (B) is dominant to blue eyes (b) Cross a heterozygous brown eyed man with a blue eyed woman. ________ X ________ B b b B b b b B bB b b BbBbb Phenotypic Ratio __________ Genotypic Ratio ____________ 2 : 2

Brown eyes (B) is dominant to blue eyes (b) Cross a heterozygous brown eyed man with a blue eyed woman. ________ X ________ B b B b B b B BB B BbBb BbBbb Phenotypic Ratio __________ Genotypic Ratio ____________ 1:2:1 3:1