SPHS Ecosystem Changes and Mutations

Biology EOC Review Session

Ecosystem Changes and Mutations

​St. Petersburg High School

• Describe changes in ecosystems resulting from seasonal variations, climate change, and succession.

In the session you will...

Test Your Knowledge!

• You will have 45 seconds to answer each question!

• Use test taking strategies: process of elimination, defining key terms, rereading the question and answer choices, etc.

Multiple Choice

A group of scientists are studying the impacts of increasing temperature related to climate change on the polar ice caps. What impacts would the scientists observe occurring within the artic ecosystem?

• Scientists would observe no changes to the polar ice caps.

• Scientists would observe a loss of habitats as the ice caps melt.

• Scientists would observe an increase in the formation of polar ice caps.

• Scientists would observe populations migrating to other areas for survival.

Multiple Choice

A team of environmentalist are assessing the biodiversity of an ecosystem by studying the ways in which the ecosystem has changed over time. The team of environmentalists concluded that the ecosystem formed from bare rock. How should they identify the type of succession taking place?

• The environmentalists concluded that primary succession has occured.

• The environmentalists concluded that secondary succession has occured.

• The environmentalists concluded that tertiary succession has occured.

• The environmentalists concluded that quaternary succession has occured.

• Ecosystems change over time, especially after disturbances, seasonal variation, or populations change and some species die out due to climate change and human impact.

• Ecological Succession is a series of somewhat predictable events that occur in a community over time.

How can an ecosystem change?

• Fold your paper in half.

• On the top left write Primary Succession

• On the top right write Secondary Succession

• As you watch the video, record the following information:

  • Causes

  • How does it grow back?

  • Which is faster/slower?

Ecological Succession

• Explain how mutations in the DNA sequence may or may not result in phenotypic change.

• Explain how mutations in gametes may result in phenotypic changes in offspring.

In the session you will...

Test Your Knowledge!

• You will have 45 seconds to answer each question!

• Use test taking strategies: process of elimination, defining key terms, rereading the question and answer choices, etc.

Multiple Choice

Mutations in an organism's DNA may be either beneficial or harmful. Which of the following statements best describes the concept of DNA mutation? 

• DNA mutation is an alteration in DNA replication that always results in phenotypic change. Mutations are usually due to radiation or other environmental factors.  

• DNA mutation is a change in the way that genes reproduce themselves, which may or may not affect phenotypic characteristics. Mutations are usually due to environmental factors or heredity.  

• DNA mutation is a change in the gene sequence, which sometimes results in phenotypic change. Mutations can be due to environmental factors, heredity, or a mistake in DNA replication.  

• DNA mutation is an alteration in the nucleus of a cell that makes certain genes unable to be copied, and they result in phenotypic change. Mutations are usually due to viruses and environmental factors.  

• DNA is genetic material made of nucleotides. Genetic mutations happen when there is a change in one nucleotide.

  • Point mutations called a substitution, where a base pair is “swapped” with the incorrect base.

  • Insertion or deletion: which will cause a frameshift mutation.

• You will see how these changes affect the way the message is transcribed to RNA and translated to protein.

Mutations

• On a sticky note, translate the mRNA sequence.

  AUG-CCC-GGC

• Compare it to the mutated mRNA sequence below:

  AUG-CCU-GGC

• With your partner, determine if there will be a change in the phenotype (physical appearance)? How do you know?

Will there be a phenotypic change?

• On a sticky note, translate the mRNA sequence.

  AUG-CAG-GGC

• Compare it to the mutated mRNA sequence below:

  AUG-UAG-GGC

• With your partner, determine if there will be a change in the phenotype (physical appearance)? How do you know?

Will there be a phenotypic change?

Knowledge Check!

• Put your knowledge to the test!

• You will have 30 seconds to answer each question!

• Use test taking strategies: process of elimination, defining key terms, rereading the question and answer choices, etc.

Multiple Choice

Mutations can occur during mitosis and meiosis. Which of the following statements about mutations is true?

• Mutations in the DNA of body cells cannot affect the individual in which they happen.

• A mutation in the DNA of a body cell can cause the cell to produce a protein that does not function.

• A mutation in the DNA of a gamete affects the body cells of the individual hat produced the gamete.

• Mutations in the DNA of body cells can cause the offspring to produce a protein that does not function.

Multiple Choice

The following mRNA sequence ACG under went a mutation and a nucleotide was substituted. The mutated mRNA sequence is now AGG. Use the codon chart to determine if a phenotypic change will occur.

• There is no phenotypic change because the mRNA sequences code for the same amino acid.

• There is a phenotypic change because the mutated mRNA sequence now codes for Gly.

• There is a phenotypic change because the mutated mRNA sequence now codes for Val.

• There is a phenotypic change because the mutated mRNA sequence codes for Arg.

Multiple Choice

A farmer stops cultivating a large tract of farmland and abandons it. The natural changes that take place soon afterward, such as the growth of wild grasses and weeds, can be considered secondary succession because _________.

• A new ecosystem develops.

• There is soil already present.

• The land is not controlled by humans.

• Wild grasses and weeds make soil from rocks.

Multiple Choice

Based on the image, identify the type of ecological succession that has occurred.

• Secondary succession because the ecosystem develops from previous soil.

• Primary succession because the ecosystem develops from bare rock.

• Secondary succession because the ecosystem suffered a forest fire.

• Neither primary or secondary succession occurred because ecosystems do not change.

Multiple Choice

Which of the following answer choices accurately describes the fastest ecological succesion?

• Primary succession occurs faster because moss and lichens grow from bare rocks.

• Primary succession occurs faster because glacial melt provides water and nutrients for the bare rock to grow plants.

• Secondary succession occurs the fastest because prescribed fires cause plants to grow back at a faster rate.

• Secondary succession because there is already rich and fertile soil for plants to grow from.

SEE YOU NEXT WEEK!