Changes to genes result in harmful, beneficial, or neutral effects to the structure and function of an organism.
The human genome is estimated to include more than 3 billion letters with an astonishingly low error rate of about 10 new mutations every time a cell divides. In a typical day, scientists estimate, the 37 trillion cells in your body will accumulate trillions of new mutations.
/ Ii / Investigate
1. LEGO Protein Synthesis - investigate how different cells build different proteins because they use different genes of the same DNA molecule.
2. Mutate A Gene Interactive - change the DNA letters and see how it affects the resulting mRNA and protein. 3. Modeling Mutations - use paper strips to model protein folding. 4. The Hairless Xolo - investigate the Mexican Hairless Dog. |
/ iII / Level Up!
During this lesson you will learn more about how characteristics of one generation are related to the previous generation.
✎Notes:
- Genes are located in the chromosomes of cells, with each chromosome pair containing two variants of each of many distinct genes.
- Each distinct gene chiefly controls the production of a specific protein, which in turn affects the traits of the individual (e.g., human skin color results from the actions of proteins that control the production of the pigment melanin).
- Changes (mutations) to genes can result in changes to proteins, which can affect the structures and functions of the organism and thereby change traits.
- Sexual reproduction provides for transmission of genetic information to offspring through egg and sperm cells.These cells, which contain only one chromosome of each parent’s chromosome pair, unite to form a new individual (offspring). Thus offspring possess one instance of each parent’s chromosome pair (forming a new chromosome pair).
- Variations of inherited traits between parent and offspring arise from genetic differences that result from the subset of chromosomes (and therefore genes) inherited or (more rarely) from mutations.
/ IV / choose your path
NOVICE [+2 points]
Sickle cell disease is an inherited blood disorder and the most common inherited disease worldwide, affecting over 400,000 babies each year. Sickle cell disease is a genetic disorder caused by a mutation in both copies of a person’s HBB gene. This gene encodes a component of hemoglobin, the oxygen-carrying protein in red blood cells. The mutation causes hemoglobin molecules to stick together, creating sickle-shaped red blood cells. Using the genetic code shown explain how the structure and function of the HBB protein changes to cause Sickle cell disease. |
ADVANCED [+4 points]
The table presents a variety of mRNA three-base sequences called codons and the amino acids for which these sequences code. Based on the information in the table, which of the following changes is LEAST likely to produce a change in an organism's structure and function? Explain how you know. GAU to GGU GAU to GUU GAU to GAA GAU to GAC |
EXPERT [+5 points]
Use the interactive above to answer the following questions: 1. What type of mutations make the greatest difference in the cells and tissues with disease-associated mutations? 2. What kind of mutation causes autism? 3. What kind of mutation causes part of the brain to grow larger than normal? 4. What causes cancer? |
MASTER [+6 points]
Develop a model to describe a genetic disorder of your choice. In your model, describe the beneficial, neutral, or harmful changes to protein function that causes beneficial, neutral, or harmful changes in the structure and function of organisms (i.e. diabetes, sickle cell anemia, cystic fibrosis, Tay-Sachs disease, muscular dystrophy). |
/ V / Knowledge Check
Sickle cell disease is a blood disorder that a child is born with. Children with Sickle cell disease make an abnormal type of hemoglobin molecule shown below. Hemoglobin is the protein molecule in red blood cells that carries oxygen to all parts of the body. With Sickle cell disease, the body's organs and tissues don't get enough oxygen.
A partial DNA sequence for normal hemoglobin and a partial DNA sequence for sickle-cell anemia are shown below:
✓ MASTERY CHECK
National Research Council 2012. A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. Washington, DC: The National Academies Press. https://doi.org/10.17226/13165
This site contains original content that may not be authorized for use by the creator and is legally used under the fair use principles section 107 of the Copyright Act of 1986 (17 U.S. Code § 107)
The official NGSS website. https://www.nextgenscience.org
LS3.A, MS-LS3-1
Develop and use a model to describe why structural changes to genes (mutations) located on chromosomes may affect proteins and may result in harmful, beneficial, or neutral effects to the structure and function of the organism. [MS-LS3-1]
This site contains original content that may not be authorized for use by the creator and is legally used under the fair use principles section 107 of the Copyright Act of 1986 (17 U.S. Code § 107)
The official NGSS website. https://www.nextgenscience.org
LS3.A, MS-LS3-1
Develop and use a model to describe why structural changes to genes (mutations) located on chromosomes may affect proteins and may result in harmful, beneficial, or neutral effects to the structure and function of the organism. [MS-LS3-1]