Genetics Practice Test PDF

# Genetics Practice Test ## Part A: Multiple Choice (50 Marks) For each of the following, select the best answer and transfer your choice to the SCANTRON provided. 1. Which of the following are the monomers (building blocks) of nucleic acids? a) Amino acids b) Sugar c) Phosphate...

# Genetics Practice Test ## Part A: Multiple Choice (50 Marks) For each of the following, select the best answer and transfer your choice to the SCANTRON provided. 1. Which of the following are the monomers (building blocks) of nucleic acids? a) Amino acids b) Sugar c) Phosphate d) Nucleotides e) Nitrogenous bases 2. Purines are double ringed nitrogenous bases. a) True b) False 3. In a molecule of DNA, adenine always pairs with which of the following? a) Thymine b) Cytosine c) Guanine d) Uracil e) None of the above 4. Which of the following is the type of bond that holds the backbone of the DNA molecule together? a) Hydrogen bond b) Ionic bond c) Phosphodiester bond d) Phosphate bond e) None of the above 5. Genes are specific sequences of DNA that code for the production of proteins. a) True b) False 6. Genes are spaced regularly along chromosomes. a) True b) False 7. The human genome is composed of approximately 25 000 genes and a bunch of non-coding regions. a) True b) False 8. The genetic code is read as a series of codons. a) True b) False 9. mRNA is an exact copy of DNA. a) True b) False 10. DNA was discovered with the invention of the microscope. a) True b) False 11. Translation occurs in the cytoplasm and involves a number of accessory molecules such as ribosomes. a) True b) False 12. Which of the following is NOT a reason that cells divide? a) Repair tissue b) Replace dead cells c) To cause the growth of an organism d) To create variation 13. Which of the following enzymes is responsible for splitting apart the DNA during replication? a) DNA polymerase b) RNA polymerase c) Helicase d) Ligase e) None of the above 14. During replication of DNA each new double helix is made of one old DNA strand and one new DNA strand. a) True b) False 15. DNA that is thin and uncoiled is referred to as... a) chromosomes b) chromatin c) chromatid d) chromomere e) None of the above 16. During which of the following stages of mitosis would crossing over occur? a) Metaphase b) Anaphase c) Telophase d) Prophase e) None of the above 17. Cytokinesis is the organized equal division of the cytoplasm and organelles and occurs at the end of the cell division cycle resulting in two genetically identical daughter cells. a) True b) False 18. During which of the following stages of mitosis do the centromeres split. a) Metaphase b) Anaphase c) Telophase d) Interphase e) Prophase 19. All mutations in DNA are harmful. a) True b) False 20. Mutations that occur during meiosis have more of an impact than mutations that occur during mitosis. a) True b) False 21. Which of the following describes a mutation that creates a premature stop signal? a) Frameshift b) Mis-sense c) Silent d) Non-sense e) Non-disjunction 22. Which of the following describes a mutation that creates an abnormal chromosome number? a) Frameshift b) Mis-sense c) Silent d) Non-sense e) Non-disjunction 23. Gametes have the haploid amount of genetic information. a) True b) False 24. Homologous chromosomes are found in all somatic cells of the human body. a) True b) False 25. When sperm and egg unite it is called fertilization and it creates a diploid zygote that will undergo mitotic divisions. a) True b) False 26. Crossing over and independent assortment creates variation during meiosis. a) True b) False 27. During which of the following stages of meiosis does synapsis occur? a) Metaphase II b) Anaphase I c) Telophase I d) Prophase II e) Prophase I 28. During which of the following stages of meiosis are cells with the haploid number of chromosomes created for the first time? a) Metaphase I b) Anaphase II c) Telophase I d) Prophase II e) Anaphase I 29. How many autosomes do humans have? a) 23 b) 72 c) 46 d) 22 e) 44 30. What causes identical twins? a) One zygote divides into two b) Two zygotes merge c) Two sperm fertilize two eggs d) Two sperm fertilize one egg e) Two zygotes divide 31. A test crossed is often used by those who are interested in doing... a) Selective breeding b) Karyotyping c) DNA sequencing d) In vitro fertilization e) None of the above. 32. A test cross can be used to determine the phenotype of an organism. a) True b) False 33. Gene therapy is the process of predicting the probability of inheriting certain features. a) True b) False 34. What type of genetic test can be used to identify the defective cystic fibrosis gene? a) Karyotype b) FISH c) Genetic testing d) Biochemical testing e) Both c and d 35. Gregor Mendel did experiments with fruit flies. a) True b) False 36. Mendel predicted that each trait is determined by two factors (alleles). a) True b) False 37. Mendel determined that if genes are located on separate chromosomes that they will be inherited independently of each other. a) True b) False 38. Which of the following describes when a heterozygous individual shows a blend of alleles making a new characteristic? a) Dominant b) Co-dominant c) Incomplete dominant d) Recessive 39. Inbreeding always produces deleterious (bad) results. a) True b) False 40. There is continuous variation in the shades of human skin. What type of inheritance does this illustrate? a) Incomplete dominance b) Codominance c) Multiple alleles d) Polygenic traits 41. Females have more sex-linked characteristics than males because of their two X chromosomes. a) True b) False 42. A Barr body is a type of body shape found in fruit flies. a) True b) False 43. In humans, curly hair (H) is dominant over straight hair (h). A woman heterozygous for hair curly marries a man with straight hair. What is the probability of their first child having straight hair? a) 0% b) 25% c) 50% d) 100% 44. A couple has two children, one of which is a boy. What is the probability that the other child is a girl? a) 0% b) 25% c) 50% d) 100% 45. If a man wanted to predict his chances of going bald, he should look at his __ for the best indication. a) mother b) father c) maternal grandparents d) paternal grandparents 46. How many different combinations of alleles can be created from and individual with the following genotypes: AABb (if you were performing a dihybrid cross)? a) 0 b) 1 c) 2 d) 3 e) 4 47. Which statement about linked genes is true? a) They tend to be inherited together b) They are more common in males c) They are more common in females d) They show independent assortment e) They cause disease 48. How much genetic variation is there in the genomes of different humans? a) 50% b) 25% c) 10% d) 1 % e) 0.1% 49. CRISPER is a gene editing technique that makes use of a protein invented by humans and can be used to repair defective genes. a) True b) False