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Essay Instructions: Using mostly references from books or professional journals, answer the 10 questions below. Answers should be at least two paragraphs in length Please do not use Assco5522 to write it. I would prefer rbwpenn as first choice or second choice blitzintheasylum to write this. They both seem to really know biology.

1. Carbon cycles through the ecosystem between the atmosphere, organisms (such as producers,
herbivores, and carnivores), and decomposers. This natural cycle maintains a somewhat
constant level of carbon in the atmosphere. The burning of fossil fuels releases carbon into the
cycle that has been trapped inside the earth. How does this affect the cycle and what problems
can this cause?

2. Using Darwin?s reasoning, explain how four species of lizards, all closely related, came to be
separate species on a Caribbean island.

3. During interphase the DNA is not visible through a microscope; it only becomes visible as
chromosomes during mitosis. Why isn?t the DNA visible during interphase and why would this
be the case?

4. How is it that, in meiosis, you can end up with four ?daughter cells? that are all genetically
different from one another?

5. Use Punnett squares to illustrate whether a type A female and a type B male can have a child
with type O blood.

6. Your friend Gorinda wants to know if there are ever mutations that don?t cause problems. What
do you tell him?

7. Compare DNA to a cookbook. The book is kept in a library and cannot be checked out
(removed). Start with the letters and words in the cookbook compared with the bases and
codons in DNA; end with the amino acid chain being folded into a protein, and a cake being
baked.

8. Your friend Thomas wants to know why scientists can?t just take the egg cell, with its own
nucleus intact, and shock it to begin cell division. How do you answer him?

9. A very heavy rainstorm floods a mountain river, changing its course and digging a deep canyon
through the soft soils of the meadow in the valley below. What happens to the mice on either
side of the valley?

10. Given the amount of sunlight that hits the plants on our planet, and the ability of plants for rapid
growth and reproduction, how come we aren?t all hip deep in dead plants?

Essay Instructions: Complete all three parts and answer all questions.
Download Graphic Organizer for answering all questions and genetics exercises in this assignment.

Part I: Genetics ? From Genes to Proteins, Mutations

Background: DNA represents the architectural blueprint for all living systems, encoding specific instructions in the sequence of its four nitrogen-containing base pairs that are necessary for building the organism.

During the process of transcription, the information in the DNA codons of a gene is transcribed into RNA.

A change in the DNA sequence, for example as a result of a ?mistake? during DNA replication, is defined as a mutation. Mutations may result in a change in the ?blueprint,? which may then change the resulting protein product.

Assignment details for part one:

Transcribe and translate EACH of the three following DNA gene sequences. Turn these in using the graphic organizer. The letters represent the DNA N-base sequences of the genes.

The first is the original gene. The next two are mutations of the original. Note that the changes (mutations) are shown in red.

Original Gene sequence 3'-T A C C C T T T A G T A G C C A C T-5

Mutated gene sequence 1 3?-T A C G C T T T A G T A G C C A T T-5'

Mutated gene sequence 2 3?-T A A C C T T T A C T A G G C A C T-5?


Also, answer the following questions:
?What is the significance of the first and last codons of an mRNA transcript?
?What meaning do these mRNA codons have for protein synthesis?
?Did the mutations result in a change in the final proteins? If so, describe the change.
?In general, why might a change in amino acid sequence affect protein function?

Part II: Inheritance of Traits or Genetic Disorders

Background: Cystic fibrosis is an inherited disease that affects the respiratory, digestive, or reproductive systems of the body, with symptoms ranging from mild to severe. Bob and Sally are recently married. Upon deciding to plan a family, both Sally and Bob find out that they are both heterozygous for cystic fibrosis, but neither of them has symptoms of the disorder.




Assignment details: Complete a Punnett Square for cystic fibrosis for this couple using the following alleles: C = normal allele; and c = allele for cystic fibrosis.



Complete the Punnett Square in the graphic organizer.

Also answer the following questions:
Based on the Punnett square, calculate chances (percentages) for the following:

?for having a healthy child (not a carrier)
?a child that is a carrier for the cystic fibrosis trait
?a child with cystic fibrosis
Be sure to submit these percentages as part of your assignment in the Graphic Organizer.
Part III: Cell division, sexual reproduction and genetic variability



Background: Eukaryotic cells can divide by mitosis or meiosis. In humans, mitosis produces new cells for growth and repair; meiosis produces sex cells (gametes) called sperm and eggs.
Although mutations are the ultimate source of genetic variability, both meiosis and sexual reproduction also can contribute to new genetic combinations in offspring.

Assignment Essay Question: How do both meiosis and sexual reproduction (fertilization) produce offspring that differ genetically from the parents? Be sure to talk about the two specific steps in meiosis that increase variability as well as the process of fertilization.
You will submit your Graphic Organizer with all answers in your Submit Assignment area.

Provide references in APA format. This includes a reference list and in-text citations for references used throughout the assignment. Note that there is a Reference page for listing sources included on the Graphic Organizer.

You will submit your Graphic Organizer with all answers.

Essay Instructions: SCIE206-1101B-18 Biology
Assignment Name: Unit 3 Individual Project
Deliverable Length: Three parts - submitted in the Graphic Organizer,
Details: Complete all three parts and answer all questions.

Download Graphic Organizer for answering all questions and genetics exercises in this assignment.

Part I: Genetics ? From Genes to Proteins, Mutations

Background: DNA represents the architectural blueprint for all living systems, encoding specific instructions in the sequence of its four nitrogen-containing base pairs that are necessary for building the organism.

During the process of transcription, the information in the DNA codons of a gene is transcribed into RNA.

A change in the DNA sequence, for example as a result of a ?mistake? during DNA replication, is defined as a mutation. Mutations may result in a change in the ?blueprint,? which may then change the resulting protein product.

Assignment details for part one:

Transcribe and translate EACH of the three following DNA gene sequences. Turn these in using the graphic organizer. The letters represent the DNA N-base sequences of the genes.

The first is the original gene. The next two are mutations of the original. Note that the changes (mutations) are shown in red.
Original Gene sequence 3'-T A C C C T T T A G T A G C C A C T-5

Mutated gene sequence 1 3?-T A C G C T T T A G T A G C C A T T-5'

Mutated gene sequence 2 3?-T A A C C T T T A C T A G G C A C T-5?


Also, answer the following questions:

What is the significance of the first and last codons of an mRNA transcript?
What meaning do these mRNA codons have for protein synthesis?
Did the mutations result in a change in the final proteins? If so, describe the change.
In general, why might a change in amino acid sequence affect protein function?


Part II: Inheritance of Traits or Genetic Disorders


Background: Cystic fibrosis is an inherited disease that affects the respiratory, digestive, or reproductive systems of the body, with symptoms ranging from mild to severe. Bob and Sally are recently married. Upon deciding to plan a family, both Sally and Bob find out that they are both heterozygous for cystic fibrosis, but neither of them has symptoms of the disorder.



Assignment details: Complete a Punnett Square for cystic fibrosis for this couple using the following alleles: C = normal allele; and c = allele for cystic fibrosis.



Complete the Punnett Square in the graphic organizer.

Also answer the following questions:
Based on the Punnett square, calculate chances (percentages) for the following:

for having a healthy child (not a carrier)
a child that is a carrier for the cystic fibrosis trait
a child with cystic fibrosis

Be sure to submit these percentages as part of your assignment in the Graphic Organizer.

Part III: Cell division, sexual reproduction and genetic variability

Background: Eukaryotic cells can divide by mitosis or meiosis. In humans, mitosis produces new cells for growth and repair; meiosis produces sex cells (gametes) called sperm and eggs.

Although mutations are the ultimate source of genetic variability, both meiosis and sexual reproduction also can contribute to new genetic combinations in offspring.

Assignment Essay Question: How do both meiosis and sexual reproduction (fertilization) produce offspring that differ genetically from the parents? Be sure to talk about the two specific steps in meiosis that increase variability as well as the process of fertilization.

You will submit your Graphic Organizer with all answers in your Submit Assignment area.

Provide references in APA format. This includes a reference list and in-text citations for references used throughout the assignment. Note that there is a Reference page for listing sources included on the Graphic Organizer.

You will submit your Graphic Organizer with all answers.

Please submit your assignment.

For assistance with your assignment, please use your text, Web resources, and all course materials. Please refer to the following multimedia course material(s):

Unit 3: Evolution & Heredity
Unit 3: The Basics of Genetics
Unit 3: Principles of Heredity and DNA

External Web links:

Unit 3: DNA, RNA, Protein
Unit 3: DNA, RNA, & Protein
Unit 3: Genetic Science Learning Center
Unit 3: Meiosis

Points Possible: 125
Date Due: Sunday, Apr 10, 2011
Objective:
Identify the relationship between reproduction, heredity and DNA
Describe the relationship between chemistry and the characteristics of living things.