Name_______________________________

Period______

Genetics and Heredity

Review for Exam 

Understanding and correctly answering these questions will be of great help on the exam. Go through the questions twice, once without your notes (to see what you remember) and once with your notes (to make sure you have the correct answers). See your instructor sometime before the exam if you have any questions.

Multiple Choice 

1. _____ Genes carry information that determines

1. alleles
2. ribosomes
3. chromosomes
4. traits

2. _____ The process that produces sex cells is

1. mitosis
2. photosynthesis
3. meiosis
4. probability

3. _____ The passing of traits from parents to offspring is called

1. probability
2. heredity
3. recessive
4. meiosis

4. _____ If you cross a white flower with the genotype pp with a purple flower with the genotype PP, the possible genotypes in the offspring are:

1. PP and pp
2. all Pp
3. all PP
4. all pp

5. _____ For the cross in the problem above, what would the phenotype be?

1. all white
2. 3 purple and 1 white
3. all purple
4. half white, half purple

6. _____ In meiosis,

1. chromosomes are copied twice
2. the nucleus divides once
3. four cells are produced from a single cell
4. two cells are produced from a single cell

7. _____ When one trait is not completely dominant over another, it is called

1. recessive
2. incomplete dominance
3. environmental factors
4. uncertain dominance

Complete each statement or sentence by filling in the blank. Some answers will not be used.

8. Sperm and eggs are known as _______________________________.

9. The ____________________ is the expression of a trait and is determined by the combination of alleles called the ______________________.

10. __________________________ produces cells with half the normal number of chromosomes

11. Different versions of the same genes are called _____________________________.

12. ________________________ is considered the father of genetics.

13. The passing of traits from parents to offspring is known as ___________________________.

14. When on allele totally hides another allele, it is an example of ____________________________.

15. ________________ are more likely to be color-blind because they have only one X and one Y chromosome.

16. In sexual reproduction, if a parent has 34 chromosomes, then ____________ will be donated to their offspring.

17. __________________________ are used to trace a trait through generations of a family.

18. An organism that has two of the same type of gene (LL) is ____________________ for that trait.

In your own words, write the definition of the following terms.

19. Heredity – _________________________________________________________________

______________________________________________________________________________

20. Dominant Trait – ____________________________________________________________

______________________________________________________________________________

21. Recessive Trait – ____________________________________________________________

______________________________________________________________________________

22. Gene – ____________________________________________________________________

______________________________________________________________________________

23. Allele – ___________________________________________________________________

______________________________________________________________________________

24. Phenotype – ________________________________________________________________

______________________________________________________________________________

25. Genotype – _________________________________________________________________

______________________________________________________________________________

26. Probability – _______________________________________________________________

______________________________________________________________________________

27. Homologous Chromosomes – __________________________________________________

______________________________________________________________________________

28. Meiosis – _________________________________________________________________

______________________________________________________________________________

29. Sex Chromosome – __________________________________________________________

______________________________________________________________________________

30. Pedigree - __________________________________________________________________

______________________________________________________________________________

Use the Punnett square below to answer the questions that follow. 

31. What is the unknown genotype?

32. If T represents the allele for tall pea plants and t represents the allele for short pea plants, what is the phenotype of each parent and of the offspring in question #24?

33. If each of the Tt offspring were allow to self-fertilize, what are the possible genotypes in the next generation?

34. What is the phenotype of each genotype in the questions #26? 

Short Answer 

35. Which sex chromosomes do females have? Which do males have?

36. Define the term recessive trait in your own words.

37. How are sex cells different from other body cells?

38. What is a sex-linked disorder? Give one example of a sex-linked disorder that is found in humans.

39. What is the difference between a trait and a characteristic? Give one example of each.

40. In a bag of chocolate candies there are 21 brown candies and six green candies. What is the ratio of brown to green? What is the ratio of green to brown?

41. Gregor Mendel used only true-breeding plants. If he had used plants that were not true-breeding, do you think he would have discovered dominant and recessive traits? Explain.

42. In cats, there are two types of ears: normal and curly. A curly eared cat mated with a normal eared cat and all of the kittens had curly ears. Are curly ears a dominant or recessive trait? Explain.

43. The allele for a cleft chin, C, is dominant among humans. What are the results of a cross between parents with genotypes Cc and cc?

44. How are genes and alleles related to genotype and phenotype?

45. Put the following in order of smallest to largest: chromosome, gene, and cell.

46. If a child has blue eyes and both her parents have brown eyes, what does that tell you about the allele for blue eyes? Explain.

47. If there are 14 chromosomes in pea plant cells, how many chromosomes are present in a sex cell of a pea?

48. Draw the six steps of mitosis. Label the step and explain what is happening.

49. Draw the eight steps of meiosis. Label the step and explain what is happening.