Genes & Proteins
Carbon Cycle
Ecosystems
Genetic Diversity
Natural Selection
Common Ancestry
100
True or false: every cell in your body has the same DNA, even though they look different from each other
True
100
Why does more carbon dioxide in the atmosphere mean a higher global temperature?
Carbon dioxide is a greenhouse gas, which means it traps heat from the sun and makes the atmosphere warmer
100
What is carrying capacity?
The maximum number of organisms that the environment can support based on what resources are available
100
Why was a single fungal infection able to wipe out an entire species of bananas?
All of the bananas were genetically identical. Therefore, since one banana didn't have resistance, none of them could have resistance.
100
Describe the steps of natural selection
A mutation occurs randomly in an individual
That mutation changes the individual's traits in a way that increases their ability to survive and reproduce
The beneficial trait gets passed on more frequently than other traits because the individuals with the less beneficial traits are less likely to survive long enough to pass their traits on
Over time the trait becomes more common in the population
100
Do you think these species are closely related? Why or why not?
They most likely are because they have very similar body structures, and body structures are coded by genes. So if they have similar body structures, then they have genes in common and are probably closely related
200
How can a mutation in DNA result in a protein with a different function?
The sequence of the DNA is what determines the sequence of amino acids. Therefore, a mutation in the DNA will change the amino acids, which will change the structure of the protein, which will change the function.
200
How do wildfires release so much carbon dioxide into the atmosphere?
The molecules of plants are made of carbon, so trees and other plants store carbon. When plants burn, fire rearranges the carbons in the plant into carbon dioxide which is released into the atmosphere
200
Why is there such a dramatic drop in population after 1850?
The population went above carrying capacity, so there was a large number of individuals competing for limited resources
200
Scientists have genetically engineered a strain of bananas which is resistant to the infection which is currently affecting bananas, called RGA2-3. Why would it be a bad idea for farmers to switch all their bananas to this new strain?
Even though this strain is resistant to the current infection, a new fungus will come along eventually and the crop will not have a defense. Since the bananas are all genetically identical, none of them will survive the new crop, and the new fungus will spread through the farms as quickly as the current infection
200
A group of mice become separated by a volcanic eruption. On one side, there is a lot of sandy areas. On the other side, it is rocky and most of the rock is black due to the hardened lava. If you look at the mice populations in a few thousand years, what would you expect to see?
The mice in the sandy area will probably be brown/tan while the mice in the rocky area will probably be black in order to camouflage. They might become different species eventually.
200
From the species represented in the tree, which species' DNA would you expect to be most similar to the DNA of a rodent and why?
The primates because they share a much more recent common ancestor with the rodents than any other species
300
What causes brain cells to look and act differently from skin cells?
Gene expression (which genes are turned off and which are turned on) is different for different types of cells. Different gene expression will cause different cell structures and functions.
300
What will happen to a plant that's exposed to higher levels of CO2 and why?
It will grow more because CO2 is one of the main ingredients for photosynthesis
300
Scientists measured how long it took bees of different species to overheat to the point of inactivity when exposed to heat wave temperatures. Describe what is being shown in the diagram below:
Bees from different areas of the world have different tolerances for heat. Bees in the Arctic overheat very quickly while bees in the Mediterranean take longer to overheat.
300
You measure the length of each fish in a population and then calculate the mean and the standard deviation (which is a measure of how spread out the data is - see the diagram below). How can you tell whether there's high genetic diversity in the population?
A high standard deviation would mean high genetic diversity, a low standard deviation would mean low genetic diversity
300
True or false (and why): species gain adaptations that they need in order to survive
False! In order for natural selection to select a trait, it has to ALREADY exist in the population! If there is no beneficial trait in the population, it is not guaranteed that a mutation will give them an adaptation (they might go extinct instead)
300
Based on the tree below, which species' DNA would you expect to be most similar to the DNA of a bird and why?
The dinosaurs because they share a much more recent common ancestor with the birds than any other species
400
What is a gene?
A gene is a segment of DNA that codes for a specific protein
400
What are the inputs (ingredients needed) and the products of photosynthesis?
Inputs (ingredients): carbon dioxide, water, sunlight
Products: oxygen, glucose (sugar)
400
Why are invasive species so harmful to local species?
They have no natural predators, and they outcompete the local species for resources
400
Why should farmers plant a variety of different banana strains which can sexually reproduce with each other?
If a new disease comes along, at least some of the population will have resistance, and those individuals can reproduce and pass on their genes.
400
Originally (in the first image), there was no bacteria in the area around the antibiotic disc. However, after a few days (in the second image), there was some bacteria growing there. Using natural selection, explain what happened.
There might have still been some bacteria near the antibiotic in the first image, but it was not enough for us to see. This is because there were some individuals in the population of bacteria that had a gene making it resistant to the antibiotic. These bacteria survived and reproduced over time, until there were enough resistant bacteria to be visible.
400
True or false (and why): Species C is more closely related to species D than it is to species B
True. The most recent common ancestor of species C and D was more recent than the common ancestor of C and B.
500
Observe the amino acid sequences and the protein structure for each version of p53. Why do versions B and C not work properly?
Version B doesn't work properly because it's missing an amino acid, and some of the amino acids got switched. Version C doesn't work properly because one of its amino acids got switched, and the different chemical properties of the amino acids cause the protein to fold differently.
500
What are the inputs (ingredients needed) and the products of cellular respiration?
Inputs (ingredients): oxygen, glucose (sugar)
Products: carbon dioxide, water, energy for the cell
500
Will the Arctic bees go extinct? Why or why not?
Bees in the polar/tundra region are at risk of extinction due to the speed of climate change. There would not be enough time for the bees to undergo natural selection in order to become less sensitive to heat.
500
A fish ladder was built to provide a way for salmon to swim over a dam. Their goal was to connect the populations, increase genetic diversity, and therefore broaden the range of fish lengths seen in the population. Based on the data below, did they succeed? Why or why not?
They did not succeed. Standard deviation (sd) is a measure of how spread out the data is from the mean. The standard deviation decreased over time, showing that they actually decreased the range of fish lengths seen in the population.
500
Antibiotics are frequently overprescribed or used incorrectly. The graph below shows that the percentage of bacterial infections that are resistant to different types of antibiotics has been increasing consistently over time. Use your knowledge of natural selection to explain why this is happening.
The increased use of antibiotics is changing the environment bacteria live in, creating a new selection pressure. The only bacteria that will survive are the ones with genes for antibiotic resistance. Over time, because bacteria produce identical clones of themselves, antibiotic resistance will become more common in the bacterial population.
500
True or false (and why): Species E is more closely related to species D than it is to species A
False. The most recent common ancestor of E and A is the same as the most recent common ancestor for E and D. This means that species E is equally related to both of them (they all split from a common ancestor at the same time)