Bio 11- Lab 11- Human Genetics PDF

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BIO 11- LAB 11- HUMAN GENETICS 

What is the homozygous dominant genotype for type of hairline? WW What is the phenotype? widow's peak

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What is the homozygous recessive genotype for finger length? ss

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What is the phenotype? long fingers

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Why does the heterozygous individual Ff have freckles? Freckles is dominant and they have one dominant allele.

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Maria and the members of her immediate family have attached earlobes. Her maternal grandfather has unattached earlobes.

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What is the genotype of her maternal grandfather? Ee

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Explain. Maria's mother has the genotype ee (results in the recessive phenotype), therefore her maternal grandfather, who has unattached earlobes, must be Ee.

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Moses does not have a bent little finger, but his parents do. Deduce the genotype of his parents. Moses genotype is ll; therefore, his parents who have bent little fingers must be Ll.

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Manny is adopted. He has hair on the back of his hand. Could both of his birth parents have had no hair on the back of the hand? No

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Explain. The presence of hair on the back of the hand is a dominant characteristic; at least one parent had to have hair on the back of the hand for Manny to have it.

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Simona and her husband have widow peaks One child has a widow's peak and the other does not. Give the possible phenotype of all persons involved. Isabella and her husband Ww X Ww Child with straight hairline ww Child with widow's peak WW or Ww

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Are dominant phenotypes always the most common in a population? No

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Explain. Phenotypes depend on inherited alleles and not on whether traits are dominant or recessive.

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With reference to Figure 11.3a, if a genetic disorder is dominant and the parents are heterozygous Aa), what are the chances that an offspring will have the disorder? 3 out of 4 (75%)

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With reference to Figure 11.3b, if parents are heterozygous (Aa) by homozygous recessive (aa), and the genetic disorder is recessive, what are the chances that an offspring will have the disorder? 50/50 (50%)

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With reference to Figure 11.3b, if the parents are heterozygous (Aa) by homozygous recessive (aa), and the genetic disorder is dominant, what are the chances that an offspring will have the disorder? 50/50 (50%)

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With reference to Figure 11.3a, if a genetic disorder is recessive and both parents are heterozygous (Aa), what are the chances that an offspring will have the disorder? 1 in 4 (25%)

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Neurofibromatosis is a dominant disorder. If a heterozygous (Aa) woman reproduces with a homozygous (aa) normal man, what are the chances a child will have neurofibromatosis? 50/50 (50%)

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Cystic fibrosis is a recessive disorder. A carrier is an individual that appears to be normal but carries a recessive allele for a genetic disorder. A man and a woman are both carriers (Aa) for cystic fibrosis. What are the chances a child will have cystic fibrosis? 1 in 4 (25%)

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Huntington disease is a dominant disorder. Drina is 25 years old and as yet has no signs of Huntington disease. Her mother does have Huntington disease (Aa), but her father is free (aa) of the disorder. What are the chances that Drina will develop Huntington disease? 50/50 (50%)

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Phenylketonuria (PKU) is a recessive disease. Mr. and Mrs. Martinez appear to be normal, but they have a child with PKU. What are the genotypes of Mr. and Mrs. Martinez? Both are heterozygous (Aa) for the disease.

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Tay-Sachs is an autosomal recessive disorder. Is it possible for two individuals who do not have Tay-Sachs to have a child with the disorder? Yes.

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Explain. If both parents are heterozygous carriers (Aa) for the disease each child has a 25% chance of Tay-Sachs.

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Does a color-blind male give his son a recessive-bearing X or a Y that is blank for the recessive allele? Y

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What is the genotype for a color-blind female? XX

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How many recessive alleles does a female inherit to be color blind? two

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What is the genotype for a color-blind male? YY

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How many recessive alleles does a male inherit to be color blind? One

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With reference to Figure 11.4a, if the mother is a carrier (X®X®) and the father has normal vision (XY), what are the chances that a daughter will be color blind? None

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A daughter will be a carrier? 50/50 (50%)

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A son will be color blind? 50/50 (50%)

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With reference to Figure 11.4b, if the mother has normal vision (XBXB) and the father is color blind (YY), what are the chances that o a daughter will be color blind? none o A daughter will be a carrier? 100% o A son will be color blind? none

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A woman with normal color vision (X®X®) whose father was color blind (X+Y), marries a man with normal color vision (XY) What genotypes could occur among their offspring?. Their children could be Bx, xx, XBY, or XY.

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What genotypes could occur if it was the normal-visioned man's father who was color blind? This means his wife is not a carrier and since both parents are normal, the children could be only PX or XY.

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Antonio's father is color blind (X+Y) but his mother is not color blind XX or XBXB). Is Antonio necessarily color blind? no

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How so? Even if his mother is XX he could inherit the X.

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Could he be color blind? Yes How so? If his mother is XX he could inherit the X".

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Make up a cross involving hemophilia that could be answered by a Punnett square, as in Figure 11.4a or b. For example, A normal man reproduces with a carrier female. What are the chances that a son will have hemophilia.

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What is the answer to your genetics problem? The answer is 50%.

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Noting that only father #3 could have given Sophia the Rh antigen, from whom did she receive the IP allele? mother

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From which parent did she receive the 11 allele? father #3.

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Is there any other possible interpretation to the results of blood typing? No.

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A man with type A blood reproduces with a woman who has type B blood. Their child has blood type 0. Using 14, P, and i give the genotype of all persons involved: man H i woman Pi, and child ii.

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If a child has type AB blood and the father has type B blood, what could the genotype of the mother be? 4 or Hi

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If both mother and father have type AB blood, they cannot be the parents of a child who has what blood type? Type O blood

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What blood types are possible among the children if the parents are 1A/ X Pi. (Hint do a Punnett Square using the possible gametes for each parent.) Types A, B, AB and O.

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Notice that neither of the original parents is affected but several children are affected. This could only happen if the trait were autosomal recessive.

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What is the genotype of the following individuals? o Generation I, individual 1: Aa This individual has to be heterozygous because some of the children are affected.

o Generation II, individual 1: aa This individual has to be homozygous recessive because he is affected. o Generation III, individual 8: Aa This has to be the case because the mother is homozygous recessive, and the individual has to inherit at least one of her recessive alleles. 

Notice that only males are affected. This could only happen if the trait were X linked recessive.

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What is the genotype of the following individuals? o Generation I, individual 1: X^X^ This female has to be a carrier because she has an affected son. o Generation II, individual 8: X4X? Unable to determine whether this female is a carrier or not because she had no children. o Generation III, individual 1: XAY This male is unaffected; therefore, he must have received a dominant allele.

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choose a key for this trait? a = normal eyelashes; A = double row of eyelashes

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Which pattern is correct? autosomal dominant

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Use correct genotypes to show a cross between Henry and Isabella and calculate the

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expected phenotypic ratio among the offspringn Aa x aa; 1:1

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What are the percentage chances of Henry and Isabella having a child with double eyelashes? 50%

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Explain why each child has the same chance for double eyelashes. Because each child has a 50% chance of receiving either and A or a from their father (Henry).

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What two methods of detecting genetic disorders were described in this section? Gel electrophoresis, genomic sequencing

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Which method is more direct and probably requires more expensive equipment to do? Genomic sequencing

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Which method probably preceded the other method as a means to detect sickle cell disease? Gel electrophoresis

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what phrase describes an individual with two dominant alleles? Homozygous dominant

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what word refers to the alleles possessed by an individual? genotype

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how many autosomes do humans have? 22 pairs

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An individual will have a widow's peak if the genotype is WW or Ww. is widow's peak an autosomal dominant or recessive trait? Autosominal dominant

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what techniques can be used to determine the genetic inheritance of offspring when the parents have known genotypes? Punnett square

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cystic fibrosis is an autosomal recessive disease. what word refers to an individual who has one recessive allele for cystic fibrosis. heterozygous carrier

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from whom does a male child inherit color blindness? Mother

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what is the genotype of a carrier of hemophilia? XH Xh

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how many dominant alleles does someone with AB blood type have? 2 dominant alleles

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can a child with AB blood type have a parent with O blood? No

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what is the presence of three chromosomes (instead of two) called, and what human chromosome is most commonly affected in this fashion? Down syndrome

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what is created when chromosomes are paired by size and shape? karyotype

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what technique is used to determine the inheritance pattern of specific traits within a family? Pedigree

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The blood types of parents and their two children are determined. The father has type A blood. The mother has type O blood. One child has type a blood and the other has type O blood. What are the genotypes of all people involved? Explain your reply. Blood Group A B AB O

Genotype AA, AO BB, BO AB OO

The father has a genotype of AO because one of his kids has O blood type. The mother is OO genotype. Child one is AO and got his O from his mother. Child two will getting both O’s from each parent from each parent making him OO. 

What are the chances that a color blind man will have a color blind grandson, (the child of the color blind man has normal vision daughter and a normal vision male)? 50% chance, if the color blinded man’s daughter is a carrier married to a normal vision male, though she has normal site if she is a carrier her son can be colorblind.

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Recall what you have learned about the fate of Homologous chromosomes during meiosis one and the sister chromatids during meiosis two, and explain how trisomy’s like trisomy 21 or poly-x syndrome could occur. A trisomy is the presence of an extra chromosome which can arise to homologous chromosome pairs not separating in meiosis one. Trisomy 21 is down syndrome in which chromosome 21 has extra genetic material. Poly syndrome is also triple X syndrome which is the result of an extra chromosome existing.

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Explain why DNA is said to have a structure that resembles a ladder. I bases are the rungs of the ladder and the sugar-phosphate backbones are the supports.

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Do the two DNA double helices following DNA replication have the same, or a different, composition? Same

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How is complementary base pairing different when pairing DNA to DNA than when pairing DNA to mRNA? Uracil replaces thymine in RNA.

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Explain why the genetic code is called a triplet code. Every three bases stands for one of the twenty amino acids in DNA.

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What role does each of the following molecules play in protein synthesis?

o a. DNA Contains inherited genetic information.

o b. mRNA Contains codons

o c. tRNA Has a specific anticodon

o d. Amino acids The unit molecules of a protein

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Which of the molecules listed in question 5 are involved in transcription? DNA and mRNA

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Which of the molecules listed in question 5 are involved in translation? mRNA, TRNA, and amino acids.

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What is the purpose of gel electrophoresis? The separate DNA molecules or amino acids.

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Why does sickle-cell hemoglobin (HbS) migrate slower than normal hemoglobin (HbA) during gel electrophoresis? HBS contains valine (no charge) instead of glutamate (has charge).

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Below is a sequence of bases associated with the template DNA strand: TAC CCC GAG CTT a. Identify the sequence of bases in the mRNA resulting from the transcription of the above DNA sequence. AUG GGG CUC GAA

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Identify the sequence of bases in the tRNA anticodon that will bind with the first codon on the mRNA identified above. UAC...