Knowledge Questions 1 Which answer correctly describes a difference between meiosis and mitosis A Cytokinesis only take place in mitosis B Exchange of genetic material occurs only in meiosis C DNA is replicated only before mitosis D Centromeres are found only in mitosis E Microtubule spindles only form in mitosis 5 A man who carries an X linked allele will pass this allele on to A half of his daughters B all of his sons C half of his sons D all of his daughters E all of his children 6 Which of the following determines a population s intrinsic rate of increase r A Amount of available resources B Maximum population size C Maximum reproductive rate D Carrying capacity of the environment 2 Which statement s about homologous genes in an individual is CORRECT A they are found on the sex chromosomes B they are two different genes found on same chromosome C they are copies of the same gene that differ in DNA sequence D they were contributed by the same parent 7 A population is in Hardy Weinberg equilibrium Which statement about the population is most likely to be CORRECT A Females in the population choose their mates at random B The population is experiencing genetic drift C There are fewer than 500 individuals in the population D There is extensive gene flow in the population 3 Which statement is FALSE A Nondisjunction refers to the failure of a pair of chromosomes to segregate properly during meiosis B Autosomes are cytoplasmic organelles that contain DNA and are capable of self replication C Karyotype refers to the number forms and types of chromosomes in a cell D Prophase marks the onset of nuclear division E Centromere refers to the region where sister chromatids join 8 Which of the following is a true statement concerning genetic variation A It is created by the direct action of natural selection B It arises in response to changes in the environment C It must be present in a population before natural selection can act upon the population D Small populations generally display higher genetic variation than large populations 4 Polygenic describes A two or more genes affecting the same phenotype B when one gene affects the expression of another gene C the ability of a single gene to affect multiple phenotypic traits D when a heterozygote individual has a phenotype intermediate between those of the two types of homozygotes E when a heterozygote exhibits phenotypes for both its alleles 9 Which is essential for speciation to occur A Sub populations must become geographically isolated from each other B Hybrid offspring can be born but are sterile 50 of the time C Gene flow between sub populations must be restricted D Formerly isolated sub populations must never re occur in the same place 1 10 Which was a central point in Darwin s theory of evolution by natural selection A More advanced organisms are less likely to go extinct B Variation in a population affects the chance a given individual will survive in its environment and reproduce C Genes change to help organisms cope with problems encountered within their environment D Mutations occur to help future generations adapt to their environment E The biological structures an organism is most likely to inherit from its parents are those that have become better suited to the environment through constant use 14 Barbie s blood type is A Ken s mother and father have type B blood Barbie and Ken first child Skip has type O blood Which answer best explains this result A There had to be a mistake as Skip should also have type A blood similar to Barbie B Barbie s genotype is AA and Ken s genotype is OO C Ken cannot be Skip s father D Barbie s genotype is AO and Ken s genotype is BO or OO E Barbie s genotype is AA and Ken s genotype is BB 15 Red green color blindness is controlled by a gene on the X chromosome A man and woman with normal vision marry Both their fathers were colour blind The probability their first child will be color blind A 0 B 1 8 C 1 4 D 1 3 E 1 2 Concept Application Questions 11 If the haploid number for a species is three each dividing diploid cell will have sister chromatids at metaphase I A 9 B 12 C 3 D 6 12 If you cross a diploid individual that is homozygous recessive for a given trait with a heterozygous diploid individual what is the probability of obtaining an offspring with the homozygous recessive phenotype A 0 B 25 C 75 D 100 E 50 16 On the pedigree shown below squares are males and circles are females Black squares or circles represent individuals that have an identifiable trait Which mode of inheritance best explains the pattern of occurrence of the trait in this pedigree 13 In flies round eyes is recessive to oval eyes curled wings is recessive to straight wings The two genes sort independently Males heterozygous for both genes are mated to females that are heterozygous for eye shape but homozygous for curled wings What proportion of the offspring should have oval eyes and normal straight wings A 1 4 B 3 16 C 3 4 D 9 16 E 3 8 A Autosomal dominant B Autosomal recessive C either autosomal or X linked recessive D X linked recessive E none of the above 2 A 20 A drug company developed a new insecticide that is highly poisonous to mosquitoes carrying West Nile virus Mass spraying of the insecticide over a 10 year period resulted in a significant reduction in mosquito populations over the first five years and a gradual increase in mosquito populations over the next five years What is the most reasonable explanation for the observed effect of the insecticide on mosquito populations A Mosquitoes from other populations in other areas moved in and replaced the mosquitoes killed by the insecticide B Genetic variants of mosquitoes resistant to the insecticide survived and transmitted their resistance to their offspring C The drug company reduced the amount of insecticide sprayed in the environment D Individual mosquitos gradually built up a tolerance to the insecticide and were able to withstand higher insecticide levels over the years E The insecticide caused favorable mutations in the mosquitoes that led to resistance dN rN K N dt K 17 The intrinsic growth rate for a population per year is 25 Using the equation above calculate how many individuals would be added to a population of 200 after if the carrying capacity of the environment is 1000 A 250 B 25 C 40 D 50 18 The frequency of the dominant allele for a gene with two alleles is 0 6 What is the expected frequency of heterozygous individuals in a population at Hardy Weinberg