Genetics - In Humans, Brown Eуе Color is Dominant, Bluе is Recessive

Date---Per Genetics Study Guide 1. In humans, brown еуе color is dominant, Ыuе is recessive. А heterozygous brown-eyed man marries а Ыue-eyed woman. What are the possiЫe genotypes and phenotypes of their offspring? t вь � 1 б Ь ь� ь.ь [ �ro�n � ( \,(\.>с_. Ь� 2. Normal pigmentation is dominant and albino is recessive. If а normal man marries an alЬino woman and they have а normal Ьоу and an alЬino girl, what are the genotypes of the parents? А r о.. ё--��+-h<-г rt'� _. :{:�,:� -�V'i\d 3. Cystic fibrosis is an autosomal recessive disorder. lf two phenotypically normal parents have а child with cy�tic fibrosis, what are the genotypes of the two parents, and the child? ) fЬ,f'�n+s rvнis-1- bL �+c..n�ovS ( in orc:kг t., lno.v� "' C.1-\;\cl ..,.;-н-. �� C"t.,<..-(ISi >JL �, .ff � 4. What is the probaЬility that their next child will also have the disease? e..,vt.� 1-\ м-е.. . f f ПIFtl r;f F- � +- 'l ч 5. Due to incomplete dominance, snapdragons are often Ыended to make interesting colors. lf you crossed а red snapdragon with а white snapdragon, what would Ье the possiЫe genotypic and phenotypic ratios of the offspring? J.. R., \<- � � с--- (<.с-- (< С'" А-\\ o#-t�("·•I\., �.-с.. ?:" � ��-.. )r..t.... � ' R.(" (t.� �с- �" J. 6. Co-dominance occurs when both alleles in а heterozygote are expressed. Roan is the term for the condition where white hair is mixed in with а base hair color. This is common in horses. lf two grey roan horses were crossed, what would Ье the genot1J)ic and E._hynotypic ratios of their offspring? � (<. ::. \ �Jt:. '2.. vt �: ' �• _t<-_,,...к._ 1 \ \o\Q.c.\<.: l. \"00.n: \ 1,,m;tc.. Q_ � -::: D I Rt. \�� "' � f!.. ��' ((' (t.\ у.)\\� tt7. Red-green color Ыindness in humans is а sex-linked recessive trait on the X-chromosome. lf а color­ Ьlind male marries а female with normal vision (that is not а carrier), what percent of their male children n ::=. ео 14tc- Ь t;" с1 t-' = 1'\ос- t'r'O. \ will likely Ье colorЫind? Y,,,t-J b\A.�k.. =- � ctoo-n r к.., ��f) 8. А female who is heterozygous for type А Ыооd marries а man that is type О. What are the possiЫe () D genotypes and phenoty s iheir children? Pr -:::. \А- 1 ° i i t ? ._ с, \ ' , .о. о • 0 , 'А--_ О •О • О 1 ' \ ' ,o o i 0 1 ,.... ,о �1 . ,.w,, JI;..,• ,(}.. ,,,.. � ,t.t\O. J..,-\ ' , о • iс f��"�. 1А-�1..о ' 9. If а сот plant has а genotype of Ttyy, what are the possiЫe genetic combinations that could Ье present in а single grain of pollen from this plant? °"" -Г� -С� 1 Fur color in cats is controlled Ьу an autosomal gene that can occur in the dominant form, (В), or the О. recessive form, (Ь). The length of the cat's fur is controlled Ьу another autosomal gene that occurs in the dominant form, (S). or the recessive form, s . The tаЫе below shows the traits for these allele codes. Gene Trait в : •. The foll es �s в -1 6S t3s ьS bs 'о$�l,SS 1eьSs\1.,�SS �\,\,Ss Lon -Ьапеd fur шg genotypes were found in а male cat а �female cat. BbSs (male) bbSS (rш:le) �s \os What will the genotype and phenotype of the offspring Ье? \oS � •. \ G'=1SS � \ \\oS4i \ \ �'oSS •. \ �\oSs ,��•• \ �\o.,(..�S�: \ ���h.of'-+. 1 1. Two heterozygous Ыасk short-haired cats mate. What is the рrоЬаЫе phenotypic ratio of their offspring? (use data tаЫе above for information) CJ lo(��Shor+ ... З tot�� ton.cз •. � w'4\i+c... $hQ("+ � \ w\-\i� t� 12. lf а human ЬаЬу Ьоу inherits а recessive allele from bls mother, in wblch circumstance would he most likely show the trait coded for Ьу the recessive allele? А. Тhе ЬаЬу inherits the dominant allele from bls father �- The allele is on an autosomal chromosome and the ЬаЬу is а twin. � The allele is on the Х chromosome. J::-- 'оо '1 cзQ...n Х- t, t"\�e. -tтta.,•b D. The allele is on the У chromosome. � rn � �'«.)�.С.("' f"'(. сА- � с.\, 31 . Below is а pedigree tracking the phenylthiocarbamide (РТС) tasting gene. 1s this gene dominant or recessive? OoN\, f'A.f"'""" (,," � �t.ne.�+- °"\ 1 41 . Write the genotype of each individual on the line( t'\\( Genotype ,::..'(( &� 1 2� 3 G, � 4 �, 11 1 , ' 2 °) °) 3 �, :tt- 6 С\ , 7 �� 8 �� .: ,�+kr '� �'N..) vs с.... •• �. ' ..--т-------t-'--1 t. \ 15. А tall реа plant sprouts up in а garden away from the rest of the реа plants. Уou want to know if the реа plant is heterozygous (hybrid) or homozygous dominant (purebred). Describe how you could find out. e,v,,s.st Uf\Kn,()\л)f"\ w�-+n е,,..... Y\,0-N\.O��o-✓-:> rЧ:C.,S�\v� \l""\d, v�c\vt\.\ (shor+ ,o\t:J.f"\+ it""\ -fl--\is C.o.Je.) И�е... о.-�+ c..,,n,.ss � 16. The prevalence of carriers for Tay-Sachs disease among Ashkenazi Jews is 2/5. If two Ashkenazi Jews marry and have а child, what is the chance that this child would have the recessive Tay-Sachs disease? � . � . ..L ? 1:, ч -= _j_ ,оо ос-- .J_ :z.s -г , \g\1\ t:. . t -r, � � it:aч .S't.ic.1-iJ 17. Challenge: Draw а pedigree for the information below. Label each person's genotype and паше. Condition of Interest: Huntington's Disease (also known as HD or Huntington's chorea) Huntington's disease is а neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and dementia. lnheritance Pattern: the allele for the normal "Huntingtin" protein is autosomal recessive; Huntington's disease is caused Ьу an autosomal dominant allele which codes for an abnormal form of the "Huntingtin" protein. Symptoms are more severe in homozygous individuals. • Use Н or h to represent the alleles. А normal man (Joseph) marries а woman (Rebecca) who is heterozygous for HD and they have four children. Two of their sons (Adam and Charles) are born healthy without HD. Charles marries а woman without HD and they have а normal daughter. Joseph and Rebecca's daughter Tasha and their last son (James) both have HD. James maпies а non-HD woman whose sister and parents also do not suffer from HD. James and his wife have three children - а normal Ьоу, а normal girl, and а son with HD.