LECTURE 2.5 - IB 150 QUESTIONS
AND CORRECT ANSWERS
largeA2gametesA2-A2Ans--ova
smallA2gametesA2withA2aA2....A2-A2Ans--flagellumA2(mobileA2tail)
gametogenesisA2-A2Ans--∙A2maleA2germA2cellA2(2n)A2resultsA2inA24A2spermA2(n)
(differentiationA2andA2maturationA2intoA2gametes)
→A2spermatogenesis
∙A2femaleA2germA2cellA2(2n)A2resultsA2inA21A2ovumA2(egg)A2(n)
→A2ovumA2hasA2massA2bulkA2ofA2originalA2cell
→A2oogenesisA2(restrictedA2toA2embryonicA2stage)
∙A2theA2divisionsA2areA2notA2equal
syngamyA2-A2Ans--
fusionA2ofA2haploidA2gametesA2andA2ultimatelyA2ofA2nucleiA2ofA2gametesA2toA2produceA2aA2
diploidA2zygote
gametogenesisA2isA2the...A2-A2Ans--productionA2ofA2gametesA2(sexA2cells)
gametesA2areA2producedA2from...A2-A2Ans--
germlineA2cells,A2stemA2cellsA2thatA2wereA2setA2asideA2fromA2theA2earliestA2stagesA2ofA2em
bryonicA2developmentA2toA2beA2theA2stemA2cellsA2thatA2willA2produceA2theA2primaryA2oocyt
esA2andA2spermatocytesA2-
A2theA2cellsA2thatA2willA2undergoA2meiosisA2toA2produceA2ovaA2(eggA2cells)A2andA2seemA2c
ells
BasicA2PatternsA2ofA2InheritanceA2-A2Ans--∙A2CysticA2fibrosis
→A2exA2ofA2aA2singleA2geneA2geneticA2disorder
→A2disorderA2ofA2theA2secretoryA2glands
→A21A2inA24,000A2births
→A2commonA2disease-causingA2allele:A2threeA2base-pairA2deletionA2inA2CFTRA2gene
→A2twoA2copiesA2ofA2theA2disease-
causingA2alleleA2areA2requiredA2forA2theA2diseaseA2toA2displayA2inA2theA2phenotypeA2ofA2th
eA2individual
∙A2homozygousA2forA2"wildA2type"A2allele
∙A2heterozygous
∙A2homozygousA2forA2"cysticA2fibrosis"A2allele
WhyA2doA2youA2thinkA2theA2heterozygousA2individualA2isA2phenotypicallyA2healthy?A2-
A2Ans--
TheyA2haveA2oneA2alleleA2thatA2codesA2forA2aA2functionalA2proteinA2thatA2canA2stillA2perfor
mA2theA2normalA2function
AND CORRECT ANSWERS
largeA2gametesA2-A2Ans--ova
smallA2gametesA2withA2aA2....A2-A2Ans--flagellumA2(mobileA2tail)
gametogenesisA2-A2Ans--∙A2maleA2germA2cellA2(2n)A2resultsA2inA24A2spermA2(n)
(differentiationA2andA2maturationA2intoA2gametes)
→A2spermatogenesis
∙A2femaleA2germA2cellA2(2n)A2resultsA2inA21A2ovumA2(egg)A2(n)
→A2ovumA2hasA2massA2bulkA2ofA2originalA2cell
→A2oogenesisA2(restrictedA2toA2embryonicA2stage)
∙A2theA2divisionsA2areA2notA2equal
syngamyA2-A2Ans--
fusionA2ofA2haploidA2gametesA2andA2ultimatelyA2ofA2nucleiA2ofA2gametesA2toA2produceA2aA2
diploidA2zygote
gametogenesisA2isA2the...A2-A2Ans--productionA2ofA2gametesA2(sexA2cells)
gametesA2areA2producedA2from...A2-A2Ans--
germlineA2cells,A2stemA2cellsA2thatA2wereA2setA2asideA2fromA2theA2earliestA2stagesA2ofA2em
bryonicA2developmentA2toA2beA2theA2stemA2cellsA2thatA2willA2produceA2theA2primaryA2oocyt
esA2andA2spermatocytesA2-
A2theA2cellsA2thatA2willA2undergoA2meiosisA2toA2produceA2ovaA2(eggA2cells)A2andA2seemA2c
ells
BasicA2PatternsA2ofA2InheritanceA2-A2Ans--∙A2CysticA2fibrosis
→A2exA2ofA2aA2singleA2geneA2geneticA2disorder
→A2disorderA2ofA2theA2secretoryA2glands
→A21A2inA24,000A2births
→A2commonA2disease-causingA2allele:A2threeA2base-pairA2deletionA2inA2CFTRA2gene
→A2twoA2copiesA2ofA2theA2disease-
causingA2alleleA2areA2requiredA2forA2theA2diseaseA2toA2displayA2inA2theA2phenotypeA2ofA2th
eA2individual
∙A2homozygousA2forA2"wildA2type"A2allele
∙A2heterozygous
∙A2homozygousA2forA2"cysticA2fibrosis"A2allele
WhyA2doA2youA2thinkA2theA2heterozygousA2individualA2isA2phenotypicallyA2healthy?A2-
A2Ans--
TheyA2haveA2oneA2alleleA2thatA2codesA2forA2aA2functionalA2proteinA2thatA2canA2stillA2perfor
mA2theA2normalA2function
