Chapter 10 Mutations and Cancer – Flashcards
21 test answers
Unlock all answers in this set
Unlock answers 21question
Allele
answer
alternative form of a gene
Unlock the answer
question
what brings about new alleles?
answer
-mutations can give rise to alleles -Nucleotides are substituted within a gene
Unlock the answer
question
What causes mutations?
answer
-Mistakes during DNA replication -DNA polymerase sometimes adds wrong nucleotide;too many or too few bases in a specific location -occurs 1/10,000 to 1/100,000 times
Unlock the answer
question
Mistakes in DNA replication can be repaired
answer
cells have a proofreading system, however not all cells are always fixed
Unlock the answer
question
What happens to a cell that is irreparable?
answer
-cells that cannot be repaired self-destruct
Unlock the answer
question
What happens to a mutation that is not repaired?
answer
a new allele is formed
Unlock the answer
question
Germ-line mutation
answer
-occurs in gametes and is passed on to offspring -found in every cell of the body -it is heritable, meaning it can be passed on from parents to offspring
Unlock the answer
question
Somatic mutation
answer
occurs in a body (nongamete) cell and is not passed on to offspring -passed on only to daughter cells of mutated cell -sporadic mutation, meaning they cannot be inherited
Unlock the answer
question
What can homogeneous genetic backgrounds lead to?
answer
Increased likelihood of passing certain mutations to offspring
Unlock the answer
question
What happens if a mutation alters the amino acid sequence of the corresponding protein?
answer
-the shape of the protein is change, changing its function
Unlock the answer
question
Hereditary cancer
answer
-often requires additional nonhereditary mutations to accumulate -Single mutations is not sufficient
Unlock the answer
question
Sporadic cancer
answer
-requires multiple somatic mutations to accumulate
Unlock the answer
question
Multihit
answer
-Hit = mutation so, multihit model is a multi mutation model
Unlock the answer
question
Mutations (hits)
answer
Arise from... -errors in DNA replication -environmental insults ex: chemicals, ultraviolet light, radiations (all factors that damage DNA
Unlock the answer
question
Mutagens
answer
any chemical or physical agent that can cause DNA mutation
Unlock the answer
question
Carcinogens
answer
any chemical agent that causes cancer by causing DNA mutations
Unlock the answer
question
What two categories of genes do cancer-causing mutations occur in
answer
-proto-oncogenes -tumor suppressor genes
Unlock the answer
