General Biology Genetics Review

General Biology Genetics Review 1. What does incomplete dominance refer to? - Answer: Incomplete dominance is a type of inheritance where neither of the two alleles is fully dominant or recessive, resulting in offspring with a phenotype that blends the traits of both parents. 2. How is co-dominance defined? - Answer: Co-dominance occurs when both alleles in a gene pair fully contribute to the phenotype of an organism. 3. What is epigenetics? - Answer: Epigenetics involves heritable changes in gene expression that can modify phenotypes without altering the underlying DNA sequence, primarily through changes in chromatin structure. 4. What is a dihybrid cross? - Answer: A dihybrid cross examines the inheritance of two distinct traits concurrently, involving individuals that possess different alleles for the same gene. 5. What are multiple alleles? - Answer: Multiple alleles refer to a gene that can have three or more different forms, which all influence a single trait. 6. Define a pedigree. - Answer: A pedigree is a graphical representation that maps out the occurrence of a genetic trait across multiple generations within a family. 7. What signifies a sex-linked gene? - Answer: A sex-linked gene is located on one of the sex chromosomes, predominantly the X chromosome. 8. What is a karyotype? - Answer: A karyotype is a visual organization of the chromosome pairs in a cell, arranged according to size and shape. 9. How do you define phenotype? - Answer: The phenotype encompasses an organism's observable traits or physical characteristics. 10. What constitutes a genotype? - Answer: The genotype is the specific genetic composition of an organism, represented by its allele combinations. 11. What is selective breeding? - Answer: Selective breeding is a technique that involves choosing specific organisms with desired traits to produce the next generation. 12. What does the term genome include? - Answer: The genome contains all of the genetic material found within an organism, including all of its chromosomes. 13. What does it mean to be heterozygous? - Answer: An organism is considered heterozygous when it has two different alleles for a particular trait. 14. What is a hybrid in genetic terms? - Answer: The term hybrid is another way to describe a heterozygous organism. 15. What defines homozygous? - Answer: An organism is homozygous if it has two identical alleles for a specific trait. 16. What is a pure-line? - Answer: Pure-line is an alternative term used to describe homozygous organisms. 17. What describes a dominant allele? - Answer: A dominant allele is one that is expressed in the phenotype whenever it is present in the genotype. 18. How is a recessive allele characterized? - Answer: A recessive allele is one that is concealed when a dominant allele is present. 19. What is artificial selection? - Answer: Artificial selection involves breeding organisms with specific traits to produce offspring that exhibit those same traits. 20. What are autosomes? - Answer: Autosomes are chromosomes that are not involved in determining the sex of an individual. 21. What is the role of sex chromosomes? - Answer: Sex chromosomes are one of the 23 pairs of chromosomes in humans that carry genes responsible for determining an individual's sex. 22. What is a polygenic trait? - Answer: Polygenic traits are characteristics influenced by two or more different genes. 23. What is the Principle of Dominance? - Answer: The Principle of Dominance is Mendel's second conclusion, stating that some alleles are dominant while others are recessive. 24. What is the Principle of Independent Assortment? - Answer: The Principle of Independent Assortment asserts that alleles for one gene segregate independently of alleles for another gene during gamete formation. 25. What is the Principle of Segregation? - Answer: The Principle of Segregation states that during meiosis, chromosome pairs divide into separate gametes, ensuring that each gamete contains only one allele for each trait.