Unit 4 Part 1 Test Review

1. Unit 4 Part 1 Test Review Is available online to study!

2. Genes are located on _______________ Chromosomes • Chromosomes are long threads of tightly coiled _________ DNA • A section of a chromosome is a __________ Gene • The two types of genes are ________ & ______ Autosomal & Sex Chromosomes

3. What does diploid mean? Containing both sets of chromosomes • What cells are diploid? Body Cells (Somatic Cells) • Do these cells divide via Mitosis or Meiosis? Mitosis • How are diploid cells represented? 2N

4. Mendel bred purebred’s in his first experiments. What does it mean to be purebred? Homozygous • How did he grow only purebreds? Allowed them to self-pollinate

5. These chromosomes are similar but not identical. One chromosome is obtained from each parent. Homologous Chromosomes • A pair of homologous chromosomes is called a ________. Tetrad

6. What is the major occurrence in Meiosis I? Homologous chromosomes separate • What is the major occurrence in Meiosis II? Sister chromatids separate • What happens during Prophase I of Meiosis? Crossing Over • Is there an interphase between Meiosis I and Meiosis II? No • What is the end result of Meiosis? 4 Genetically Unique Haploid Cells

7. Your father’s gametes are called ___________. Sperm • These sex cells contain 22 autosomes and _________. Either an X or Y chromosome • Your mother’s gametes are called _______. Eggs • These sex cells contain 22 autosomes and _____. Only X chromosomes

8. Homozygous refers to ______________ alleles. Same • Heterozygous refers to _____________ alleles. Different • Dominant genes are always represented with a _____________ letter. Uppercase • Recessive genes are always represented with a _________ letter. Lowercase

9. A physical description like tall or blue eyes is an example of a _____________. Phenotype • An organisms ____________ is represented by alleles. Genotype Example (Genotype-Phenotype) TT- tall, Tt-tall, tt- short HH- curly hair, Hh- wavy hair, hh-straight hair

10. What law states that organisms inherit two copies of each gene, but separate those copies before donating only one copy to each of their offspring? Law of Segregation • What law states that some alleles are dominant and others are recessive? Law of Dominance • What law states that the segregation of alleles of one trait does NOT affect the segregation of the alleles of another trait. (This law also explains genetic variation) Law of Independent Assortment

11. A _____________ cross shows one trait. Monohybrid • A ____________ cross shows two traits. Dihybrid • What are the gametes for this genotype for a dihybrid cross: AaBB AB, AB, aB, aB • What are thegametes for this genotype for a dihybrid cross: DdEe DE, De, dE, de

12. A blue butterfly crossed with a yellow butterfly that produced green butterflies is an example of ________________. Incomplete Dominance • A brown cow crossed with a white cow that produced brown and white spotted cows is an example of ________________. Codominance • In the two examples above, both of their genotypes are _____________. Heterozygous

13. Red-green color blindness and hemophilia are considered _________________. Sex Linked Traits • This is because these genes are located on the ________ chromosomes. Sex, X and Y chromosomes

14. Complete a Dihybrid Cross BB-bald Bb- thin hair bb-hairy TT- tall Tt- average tt-short Show the cross between a woman with thin hair and tall height with a man that is hairy and short in height. BbTT X bbtt Show the genotypic and phenotypic ratios.