1. Unit D Vocabulary Genetics/Heredity

2. 1. Gene A specific sequence of DNA that determines one or more traits.

3. 2. Heredity The passing of traits to offspring (from its parent or ancestors). This is the process by which an offspring cell or organism acquires or becomes predisposed to the characteristics of its parent cell or organism.

4. 3. Inherited The passage of traits from parent to offspring.

5. 4. Trait A specific version of a characteristic that varies from one individual to another.

6. 5. Offspring Product of reproduction, a new organism produced by one or more parents.

7. 6. Asexual Reproduction Process by which organisms make exact copies of themselves without the union of gametes (sperm and egg cells).

8. 7. Clone An offspring produced by asexual reproduction, either naturally or through artificial processes.

9. 8. Egg Cell A cell produced by a female that contains half of the number of chromosomes present in other body cells. A female reproductive cell.

10. 9. Fertilization The union of a male sperm and a female egg to form a zygote.

11. 10. Mutation A change in the DNA of a gene that can lead to a different trait.

12. 11. Sexual Reproduction Process by which a sperm cell from a male unites with an egg cell from a female to produce offspring that inherit traits from both.

13. 12. Sperm Cell Cell produced by a male that contains half of the chromosomes of body cells. A male sex cell.

14. 13. Allele A variant, or version, of a gene.

15. 14. Dominant The genetic condition in which one copy of a version of a gene (an allele) in an individual gives rise to an observed trait.

16. 15. Recessive The genetic condition in which a trait is not observed in the phenotype of a heterozygous individual.

17. PhenotypeGenotype

18. 16. Genotype An individual’s pair of alleles for a specific gene or group of genes that determine a trait.

19. 17. Heterozygous An organism that has two different alleles for a specific trait.

20. 18. Homozygous An organism that has two identical alleles for a specific trait.

21. 19. Phenotype An organisms observable traits.

23. 20. Punnet Square A diagram that is used to show the likelihood of each outcome of a breeding experiment.

24. 21. Chromosome A strand of DNA- and sometimes associated with proteins- that contain the genes that store hereditary information.

25. 22. Cell Division The process by which a parent cell splits to form two daughter cells in order for an organism to grow and replace injured or worn out cells or to reproduce via asexual reproduction.

26. 23. Carrier An organism that carries and transmits a disease without exhibiting symptoms. In the case of a genetic disease or condition, the recessive gene that causes the condition is masked in a heterozygous individual.

27. 24. DNA Deoxyribonucleic acid; a long double-helical molecule, present in chromosomes, that contains the genes.

28. 25. Co-Dominance A condition in which two traits have equal dominance and, as a result, both traits can be observed distinctly in a heterozygous individual.

29. 26. Incomplete Dominance A condition in which a heterozygous individual shows a trait that is different from either homozygote, and usually intermediate between them.

30. 27. Pedigree A tree constructed from data collected on a single trait within a family.

31. 28. DNA Fingerprinting A technique used to generate a unique pattern of DNA sequence from an individual, in order to identify the individual.