SFSU Biology 230 Exam Questions with Answers

SFSU Biology 230 Exam Questions with Answers What are the relationships among genomes, chromosomes, genes, alleles, proteins, traits, and mutations? - Answer-Genomes are chromosomes that are in gametes. Alleles are different versions of the same gene. Proteins directly impact traits. A mutation is an allele and something could be different about the protein. What are the similarities and differences in what DNA, RNA, and proteins are made of? - Answer-DNA, RNA, and proteins are made of macromolecules. DNA and RNA is made of nucleic acids and proteins are made of amino acids. Where are DNA, RNA, and proteins inside a cell? - Answer-DNA is held in the nucleus, RNA is held in the cytoplasm, and proteins are held in the cell membrane. How does DNA code for RNA? - Answer-DNA codes for RNA by transcription or coping the DNA and replacing the Ts with Us. How does RNA code for proteins? - Answer-RNA is translated by ribsomes to make a chain of amino acids to become proteins. What are codons? - Answer-The three nucleotide sequence translated into a single protein. What is the function of DNA? - Answer-To code for proteins. What is the function of RNA? - Answer-To make proteins. What is the function of proteins? - Answer-To express traits and do common functions. What do the terms transcription and translation mean in biology? - Answer-Transcription is copying DNA to make RNA and translation is copying RNA into a protein. What type of cells contain the genes for certain traits, like eye color? - Answer-Gametes What percentage of the human genome is thought to code for protein? - Answer-1% What is known about the rest of the DNA sequences, sometimes called "non-coding" or junk DNA? - Answer-It makes non-coding RNA. What are introns? - Answer-Introns are parts of the RNA that are removed after it is coded from DNA. What are exons? - Answer-Exons is what is translated to make proteins. Who is Tracy Johnson and what does she work on? - Answer-A scientist who studies how spliceosomes recognize introns and remove them. What is one way that transcription and translation different between prokaryote and eukaryotes? - Answer-Prokaryotes has its DNA in the cytoplasm, its chromosomes are circular, and it has no histones or introns. Eukaryotes have its DNA in the nucleus, its chromosomes are linear, and it has introns and exons. It is wrapped around histones. How can small changes in the DNA result in big, small, or no changes in the physical characteristics of a living thing? - Answer-DNA is what is coded for proteins which directly impacts traits. What are different ways that DNA can be mutated to produce different proteins than originally coded for? - Answer-Substitution Insertion Deletion What are frame shift mutations? - Answer-When nucleotides are inserted or deleted What are point mutations? - Answer-Affects one or few nucleotides What are deletion mutations? - Answer-Removal of one or more nucleotides What are insertion mutations? - Answer-Addition of one or more nucleotides What are substitution mutations? - Answer-Substitutes one nucleotide for another What are silent mutations? - Answer-Does not change the result Does a substitution always change the amino acid sequence of a protein? - Answer-No Does an insertion mutation always change the amino acid sequence of a protein? Why or why not? - Answer-Yes because a nucleotide is added Does an deletion mutation always change the amino acid sequence of a protein? - Answer-Yes because a nucleotide is removed What is sickle cell anemia? - Answer-Red blood cells become half-moon shaped. What change in DNA causes sickle cell anemia to occur? - Answer-A mutation in hemoglobin What would happen if a gene had two nucleotides inserted as a mutation? - Answer-It would chance the final result What would happen if a gene had three nucleotides inserted as a mutation? - Answer-It would chance the final result Does the place in the DNA where the extra nucleotides are inserted matter? - Answer- Yes What are examples of a mutagen? - Answer-X-rays What is cancer? - Answer-When cells divide uncontrollably What role do mutations play in cancer? - Answer-Multiple mutations are needed to cause cancer What kinds of things can cause mutations that lead to cancer? - Answer-UV rays X-rays Radioactivity Chemicals Cigarette smoke Viruses