Assignment Type: Individual Project Deliverable Length: Completed Punnett Square and Answers to all Questi
Points Possible: 125 Due Date: 4/12/2009 11:59:59 PM CT
Part 1: Genetics: From Genes to Proteins
Convert the following DNA sequence into its RNA equivalent and then using the genetic code, convert that RNA sequence into the amino acid sequence.
5’–TACTTCTTCAAGACT-3’
For this above DNA sequence, what information is contained in the genetic code for the first and last codon? Be specific.
Part 2: Genetics Problem - Human Blood Types
Mendel is the father of modern genetics, but there are some genetic characteristics that cannot be explained by simple Mendelian genetics. Such is the case with the human blood types in which there are 3 alleles for the same gene, A B, and o. A parent can pass allele A, B, or o to the offspring based on the parent’s genotype.
From these 3 alleles, there are 4 blood types (phenotypes): A, B, AB, and O, and there are six genotypes: AA, Ao, BB, Bo, AB, or oo. This is an example of codominance in which both A and B alleles are codominant to each other.
Blood types can be used in forensics to determine if blood is from the victim or criminal. Blood types can be used to determine parental source in situation where the father is unknown; however, blood types can only eliminate certain blood types. DNA fingerprinting is a better method that is used often in criminal and parental determination cases.
Punnett squares
Punnett squares such as the one shown above are used to determine the probabilities (percentages) for genotypes of offspring given specific genotypes for the parents.
1.
In the example above, the Punnett Square represents a cross (mating) between a male (on the left side) with blood type AB, and a female, (top of square), with blood type B, genotype BB.
Fill out and turn in the Punnett square for AB x BB above. And, answer the following questions for the cross represented above. Make sure you understand the difference between phenotype (blood type) and genotype. The Punnett Square shows the possible genotypes. When answering the questions, percent (probability) calculations and your answers should be in terms of the phenotypes (the blood types) and NOT the genotypes.
1. What are the possible blood types for the offspring?
2. What are the ratios or percentages for each possible blood type from this cross?
3. What blood type is not possible from this cross?
You will be turning in 1 completed Punnett square and answers to the questions for Parts 2A.
Part 3: Cell division, mutations, and genetic variability.
Eukaryotic cells can divide by mitosis or meiosis. In humans, mitosis produces new cells for growth and repair. And, meiosis produces sex cells (gametes), called sperm and eggs. Changes or mutations in genes in sex cells can be inherited by human offspring. Genetic variation in a population of organisms is good; however, sometimes mutations can be harmful or cause genetic disorders.
Briefly, answer the following two questions. List and cite your references for this:
1. How do meiosis and sexual reproduction (fertilization) produce offspring that differ genetically from the parents? Be sure to talk about both meiosis and fertilization.
2. Name and describe one example of a human disorder that is inherited and also describe the specific inheritance pattern. For this question, pick disorders that result from mutations in DNA or chromosome number rather than examples such as a genetic tendency for a disorder such as cancer.
what are the other parts of cells
Part 1: Genetics: From Genes to Proteins
To convert the given DNA sequence into its RNA equivalent, we need to replace T's with U's since RNA uses uracil instead of thymine. The DNA sequence is:
5’–TACTTCTTCAAGACT-3’
The RNA sequence would be:
5'-UACUUCUUCAAGACU-3'
Using the genetic code, we can then convert the RNA sequence into the amino acid sequence. Here is the breakdown:
UAC - Tyrosine (Tyr)
UUC - Phenylalanine (Phe)
UUC - Phenylalanine (Phe)
AAG - Lysine (Lys)
ACU - Threonine (Thr)
So, the amino acid sequence for the given DNA sequence is Tyr-Phe-Phe-Lys-Thr.
Regarding the genetic code for the first and last codon, for the first codon "TAC" in the DNA sequence, the genetic code tells us that it codes for the amino acid tyrosine (Tyr). For the last codon "ACT", the genetic code tells us that it codes for the amino acid threonine (Thr).
Part 2: Genetics Problem - Human Blood Types
1. The possible blood types for the offspring of AB x BB are A and B. The child cannot have blood type AB because it is impossible to inherit both A and B alleles from the parents in this case.
2. The ratio or percentage for each possible blood type from this cross would be as follows:
- 50% chance of blood type A
- 50% chance of blood type B
3. Blood type O is not possible from this cross. Blood type O can only occur if both parents carry the "o" allele. In this case, the parent with blood type AB does not have the "o" allele.
Part 3: Cell division, mutations, and genetic variability
1. Meiosis and sexual reproduction (fertilization) produce offspring that differ genetically from the parents through the process of genetic recombination. Meiosis is the division of sex cells (gametes) that reduces the chromosome number by half. During meiosis, crossing over occurs between homologous chromosomes, resulting in the exchange of genetic material. Additionally, during fertilization, the two gametes (sperm and egg) combine to form a zygote with a unique combination of genes from the parents.
Reference: Campbell Biology textbook, 11th edition, Chapter 13
2. One example of a human disorder that is inherited is Down Syndrome. Down Syndrome is caused by the presence of an extra copy of chromosome 21 (trisomy 21). It is inherited when there is an error in the process of chromosome division during gamete formation. This disorder is not inherited in a classic Mendelian pattern but rather due to a chromosomal abnormality.
Reference: Genetics Home Reference - Down Syndrome
To complete this assignment, you will need to follow the instructions provided for each part and use the given information to find the answers. Here is a step-by-step guide for each part of the assignment:
Part 1: Genetics: From Genes to Proteins
1. Convert the given DNA sequence (5' - TACTTCTTCAAGACT - 3') into its RNA equivalent. Remember that in RNA, thymine (T) is replaced by uracil (U).
- The RNA sequence will be 3' - AUGAAGAAAGUUCUG - 5'
2. Use the genetic code to convert the RNA sequence into the amino acid sequence.
- We can use a codon table to find the corresponding amino acids for each codon in the RNA sequence.
- The amino acid sequence for the given RNA sequence is Methionine - Lysine - Lysine - Serine - Leucine.
3. The information contained in the genetic code for the first and last codon can be determined by looking at the codon table.
- The first codon, AUG, codes for the amino acid Methionine, which serves as the start codon for protein synthesis.
- The last codon, UGA, codes for the amino acid Stop, indicating the termination of protein synthesis.
Part 2: Genetics Problem - Human Blood Types
1. Fill out the Punnett square for AB x BB to find the possible genotypes of the offspring.
- In this cross, the male has blood type AB (genotype AB) and the female has blood type B (genotype BB). Fill in the Punnett square based on these genotypes to find the possible genotypes of the offspring.
2. Answer the questions for the cross represented in the Punnett square.
a. What are the possible blood types for the offspring?
- The possible blood types for the offspring are AB and B.
b. What are the ratios or percentages for each possible blood type from this cross?
- The ratio of possible blood types from this cross is 1:1, meaning there is an equal chance for an offspring to have blood type AB or B.
c. What blood type is not possible from this cross?
- The blood type A is not possible from this cross because neither parent has the A allele.
Part 3: Cell division, mutations, and genetic variability.
1. Explain how meiosis and sexual reproduction (fertilization) produce offspring that differ genetically from the parents.
- Meiosis is a cell division process that produces haploid cells (gametes) with half the number of chromosomes as the parent cell. During meiosis, homologous chromosomes exchange genetic material through a process called recombination (crossing over), resulting in genetic variation.
- Sexual reproduction occurs when two gametes (sperm and egg) fuse during fertilization, combining their genetic material to form a unique offspring. Since the gametes produced through meiosis are genetically different from each other, combining different gametes through fertilization creates offspring that inherit a unique combination of genes from both parents, resulting in genetic diversity.
2. Provide an example of a human disorder that is inherited and describe the specific inheritance pattern.
- One example of a human disorder that is inherited is Cystic Fibrosis. Cystic Fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. It is inherited in an autosomal recessive pattern, which means an individual must inherit two copies of the mutated CFTR gene (one from each parent) to develop the disorder.
Nothing here! If you were trying to "cut and paste" it won't work. You need to type it all out.
Sra