1. A Population Genetics Case Study: The Cheetah

CheetahWhen chasing down prey, cheetahs have a top sprinting speeds of up to 60 miles (100 kilometers) per hour. It’s hard to imagine a better adapted animal.

But even apart from human-caused problems related to the destruction of their habitat, cheetahs are in trouble. For one thing, cheetahs have extremely low fertility. Studies of cheetah sperm (collected by investigators who were trying to figure out why it was so hard to breed captive cheetahs in zoos and wildlife parks), have shown that

  1. Up to 79% of the sperm cells in any cheetah sperm sample are abnormal.
  2. Cheetah sperm count is low (only 25 million per ejaculate, much lower than in other species of cats).

The underlying problem is that cheetahs have extremely low genetic variability. It’s almost as if all cheetahs were members of the same family. They have much less genetic variation than other wild cats (source: The Cheetah in Genetic Peril, Scientific American,  O’Brien, Wildt, and Bush). As we’ll see, this genetic uniformity could put the cheetah at risk of extinction. With very little variation, their ability to adapt to environmental change is limited.

To understand the cheetah’s genetic situation, we need to look at how genes are distributed and how genes change in populations. This field is known as population genetics. Let’s start.

2. Interactive Reading: The Gene Pool, Fixed Alleles, Variable Alleles

To increase your retention of what you’re reading, I’ve pulled out a few words from the passage below. Drag them back into the text as you read.

[qwiz style=”width: 600px; border: 1px solid black;” qrecord_id=”sciencemusicvideosMeister1961-Pop-gen: Gene Pool, Fixed Alleles IR”]

[h]The Gene Pool, Fixed Alleles, and Variable Alleles

[i]A gene pool

[q labels = “top”]

The first concept for us to understand is the gene pool. The gene pool is the total of all the ________ for all of the genes in a population.

To understand this concept, start by thinking of yourself. It took about 20,000 genes to spell out how to make your body, and to tell your body’s cells how to behave. You inherited these 20,000 genes from your ___________, receiving one copy from your mother, and a second from your father.

Now, you’re not the only person who has these ___________ genes. You __________ your genes from your parents, so they have them. If you have siblings, they have these genes, too. So do your cousins. In fact, every human being has the ______ set of genes.

[l]20,000

[fx] No. Please try again.

[f*] Excellent!

[l]alleles

[fx] No, that’s not correct. Please try again.

[f*] Good!

[l]inherited

[fx] No, that’s not correct. Please try again.

[f*] Good!

[l]parents

[fx] No, that’s not correct. Please try again.

[f*] Good!

[l]same

[fx] No, that’s not correct. Please try again.

[f*] Good!

[q labels = “top”]

Two homologous chromosomes, one from the mother, and one from the father. At the locus for gene “A,” both alleles are the the same. At the locus for gene “B,” the two alleles are different (“b” and “B”)

Put together, all of these genes can be thought of as a cookbook. In this analogy, each of our 20,000 genes is a different _________: one recipe may be for a muscle protein. A second one may be for a digestive enzyme. To develop from a zygote, and for your body to properly function, you need to have two ________ of each of these 20,000 recipes. But those recipes aren’t ____________. In the same way as your recipe for tomato sauce might be slightly different from mine, it’s also possible that your mother’s genetic recipe for making a particular enzyme might be slightly different from your father’s. In genetics, these ____________ versions of a gene are known as alleles.

You can also think of this in terms of where genes are on chromosomes. A gene’s physical location on a chromosome is called its locus. At any locus, the DNA is going to code for the protein that this gene is responsible for. But the specific nucleotide ___________ (the DNA _________) might be different.

[l]alternative

[fx] No. Please try again.

[f*] Excellent!

[l]bases

[fx] No. Please try again.

[f*] Excellent!

[l]copies

[fx] No. Please try again.

[f*] Great!

[l]identical

[fx] No. Please try again.

[f*] Good!

[l]recipe

[fx] No. Please try again.

[f*] Great!

[l]sequence

[fx] No. Please try again.

[f*] Excellent!

[q labels = “top”]

Now, zoom out from thinking about your own genes to thinking about the genes of an entire population. Every member of that _________ will have the same genes. But there will be a variety of _______. On a very small scale, in a population with only five individuals and five genes, you can think about it like this.

gene locus 1 gene locus 2 gene locus 3 gene locus 4 gene locus 5
Individual 1 allele 1a only allele 2a only allele 3b only allele 4a only allele 5a only
Individual 2 alleles 1a and 1b allele 2a only allele 3c only allele 4a only allele 5b only
Individual 3 allele 1b only allele 2a only allele 3a only allele 4a only alleles 5a and 5b
Individual 4 allele 1a only allele 2a only allele 3b and 3c allele 4a only alleles 5a and 5b
Individual 5 alleles 1a and 1b allele 2a only allele 3b only allele 4a only  allele 5b only

Focus first on gene locus 1. If you follow the column downward, you can see that it has two alleles, allele 1a and allele 1b. By contrast, gene 2 has only one allele. Genes that have only one allele in an entire population are known as fixed alleles. Gene 3 has three alleles, the kind of situation that you’d find with the alleles for the ABO _______ type system, which also has three alleles (A, B, and o). Gene 4 is also a ________ allele.

Now look at the individuals. Individual 1 happens to be ____________ for all five of the genes. But individual two is heterozygous for gene 1, and homozygous for the other genes.

[l]alleles

[fx] No. Please try again.

[f*] Good!

[l]blood

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[l]fixed

[fx] No, that’s not correct. Please try again.

[f*] Great!

[l]homozygous

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[l]population

[fx] No, that’s not correct. Please try again.

[f*] Correct!

[x]Great job. Now continue on to the quiz below, which will help you master the concepts you just read about. Or, if you’d like to read this material again, click below.

[restart]

[/qwiz]

3. Checking Understanding

In this tutorial, we started by looking at cheetahs and their low genetic variability. We followed that by examining four concepts

  1. population genetics
  2. alleles
  3. gene pools
  4. fixed alleles

The quiz below will test you on your mastery of these concepts.

[qwiz random = “true” style=”width: 600px; border: 3px solid black;” qrecord_id=”sciencemusicvideosMeister1961-Pop-gen: Key Terms 2019″]

[h]Population genetics key terms

[i]A gene pool

[q topic = “alleles in populations”] The study of genes in populations is called

[c]IHBvcHVsYXRpb2 4gZ2VuZXRpY3M=[Qq]

[c]IHBvcHVsYXRpb24gc2NpZW5jZQ==[Qq]

[c]IG1vbGVjdWxhciBnZW5ldGljcw==[Qq]

[f]IENvcnJlY3QuIFRoZSBzdHVkeSBvZiBnZW5lcyBpbiBwb3B1bGF0aW9ucyBpcyBjYWxsZWQg4oCYcG9wdWxhdGlvbiBnZW5ldGljcy7igJk=[Qq]

[f]IE5vLiDigJhQb3B1bGF0aW9uIHNjaWVuY2XigJkgaXMgdG9vIGJyb2FkLiBDaG9vc2UgYW4gYW5zd2VyIHRoYXQgaW5jbHVkZXMgYm90aCDigJhnZW5ldGljc+KAmSBhbmQg4oCYcG9wdWxhdGlvbuKAmQ==[Qq]

[f]IE5vLiDigJhNb2xlY3VsYXIgYmlvbG9neeKAmSBmb2N1c2VzIG9uIHRoZSBtb2xlY3VsZXMgb2YgaGVyZWRpdHksIHN1Y2ggYXMgRE5BLiBDaG9vc2UgYW4gYW5zd2VyIHRoYXQgaW5jbHVkZXMgYm90aCDigJhnZW5ldGljc+KAmSBhbmQg4oCYcG9wdWxhdGlvbuKAmQ==

Cg==

[Qq]

[q topic = “alleles in populations”] An alternative version of a gene is called a(n)

[c]IGdlbmUtYWx0[Qq]

[c]IGFsbG VsZQ==[Qq]

[c]IGdlbmUgdmFyaWFudC4=[Qq]

[f]IE5vLiBZb3UgbWFkZSBhIHNlbnNpYmxlIGNob2ljZSwgYnV0IHRoYXTigJlzIG5vdCB0aGUgdGVybSBpbiB1c2UuIFRoZSDigJhhbOKAmSB0aGF0IHN0YXJ0cyB0aGUgd29yZCDigJhhbHRlcm5hdGl2ZeKAmSBpcyBhIGNsdWUgdG8gdGhlIGFuc3dlci4=[Qq]

[f]IENvcnJlY3QuIOKAmEFsbGVsZeKAmSBpcyBhbiBhbHRlcm5hdGl2ZSB2ZXJzaW9uIG9mIGEgZ2VuZS4=[Qq]

[f]IE5vLiBZb3UgbWFkZSBhIHNlbnNpYmxlIGNob2ljZSwgYnV0IHRoYXTigJlzIG5vdCB0aGUgdGVybSBpbiB1c2UuIFRoZSDigJhhbOKAmSB0aGF0IHN0YXJ0cyB0aGUgd29yZCDigJhhbHRlcm5hdGl2ZeKAmSBpcyBhIGNsdWUgdG8gdGhlIGFuc3dlci4=

Cg==

[Qq]

[q topic = “alleles in populations”] Alleles can be thought of as different ‘recipes’ for the same

[c]IHRyYWl0[Qq]

[c]IHByb3RlaW4=[Qq]

[c]IGdlbmU=[Qq]

[c]IGFsbCBvZiB0 aGUgYWJvdmU=[Qq]

[f]IE5vLiBZb3VyIGFuc3dlciBpcyBpbmNvbXBsZXRlLiBBbGxlbGVzIGFyZSByZWNpcGVzIGZvciBkaWZmZXJlbnQgdmVyc2lvbnMgb2YgdGhlIHNhbWUgdHJhaXQuIEJ1dCB0aGVyZSBhcmUgb3RoZXIgZXF1YWxseSBjb3JyZWN0IHdheXMgdG8gdGhpbmsgYWJvdXQgd2hhdCB0aGVzZSBnZW5ldGljIHJlY2lwZXMgYXJlIGZvci4gQ2hvb3NlIGEgZGlmZmVyZW50IGFuc3dlciBuZXh0IHRpbWUu[Qq]

[f]IE5vLiBZb3VyIGFuc3dlciBpcyBpbmNvbXBsZXRlLiBBbGxlbGVzIGFyZSByZWNpcGVzIGZvciBkaWZmZXJlbnQgdmVyc2lvbnMgb2YgdGhlIHNhbWUgcHJvdGVpbi4gQnV0IHRoZXJlIGFyZSBvdGhlciBlcXVhbGx5IGNvcnJlY3Qgd2F5cyB0byB0aGluayBhYm91dCB3aGF0IHRoZXNlIGdlbmV0aWMgcmVjaXBlcyBhcmUgZm9yLiBDaG9vc2UgYSBkaWZmZXJlbnQgYW5zd2VyIG5leHQgdGltZS4=[Qq]

[f]IE5vLiBZb3VyIGFuc3dlciBpcyBpbmNvbXBsZXRlLiBBbGxlbGVzIGFyZSByZWNpcGVzIGZvciBkaWZmZXJlbnQgdmVyc2lvbnMgb2YgdGhlIHNhbWUgZ2VuZS4gQnV0IHRoZXJlIGFyZSBvdGhlciBlcXVhbGx5IGNvcnJlY3Qgd2F5cyB0byB0aGluayBhYm91dCB3aGF0IHRoZXNlIGdlbmV0aWMgcmVjaXBlcyBhcmUgZm9yLiBDaG9vc2UgYSBkaWZmZXJlbnQgYW5zd2VyIG5leHQgdGltZS4=[Qq]

[f]IENvcnJlY3QuIEFsbGVsZXMgYXJlIHJlY2lwZXMgZm9yIGRpZmZlcmVudCB2ZXJzaW9ucyBvZiB0aGUgc2FtZSBnZW5lLiBHZW5lcyBjb2RlIGZvciBwcm90ZWlucy4gQW5kIHByb3RlaW5zIGFyZSB0aGUgbW9zdCBpbXBvcnRhbnQgZmFjdG9yIGJlaGluZCBhbiBvcmdhbmlzbeKAmXMgdHJhaXRzIChlaXRoZXIgZGlyZWN0bHksIG9yIHRocm91Z2ggY29udHJvbGxpbmcgdHJhaXRzIHRocm91Z2ggZW56eW1lcyku

Cg==

[Qq]

[q topic = “alleles in populations”] The total of all the alleles for all of the genes in a population is known as its

[c]IGdlbmV0aWMgZGl2ZXJzaXR5IGluZGV4Lg==[Qq]

[c]IGNvbWJpbmVkIGFsbGVsZSBlbnNlbWJsZS4=[Qq]

[c]IGdlbmUg cG9vbC4=[Qq]

[f]IE5vLiBUaGluayBvZiBhbGwgb2YgdGhlIGdlbmVzIGluIGEgcG9wdWxhdGlvbiBhcyB3YXRlciBpbiBhIHBvb2wsIGFuZCB5b3XigJlsbCBiZSBhYmxlIHRvIGZpZ3VyZSBvdXQgdGhlIGFuc3dlci4=[Qq]

[f]IE5vLiBUaGlzIHdvdWxkIGJlIGEgcHJldHR5IGdvb2QgZGVzY3JpcHRpb24sIGJ1dCBpdOKAmXMgbm90IHRoZSBvbmUgaW4gdXNlLiBUaGluayBvZiBhbGwgb2YgdGhlIGdlbmVzIGluIGEgcG9wdWxhdGlvbiBhcyB3YXRlciBpbiBhIHBvb2wsIGFuZCB5b3XigJlsbCBiZSBhYmxlIHRvIGZpZ3VyZSBvdXQgdGhlIGFuc3dlci4=[Qq]

[f]IENvcnJlY3QuIFRoZSDigJhnZW5lIHBvb2zigJkgaXMgdGhlIHRvdGFsIG9mIGFsbCB0aGUgYWxsZWxlcyBmb3IgYWxsIG9mIHRoZSBnZW5lcyBpbiBhIHBvcHVsYXRpb24u

Cg==

[Qq]

[q topic = “alleles in populations”] The diagram below represents a gene pool for a population of five individuals with five genes. Is individual 4 homozygous or heterozygous for gene 3?

[c]IGhvbW96eWdvdXM=[Qq]

[c]IGhldGVyb3 p5Z291cw==[Qq]

[f]IE5vLiBUbyBiZSBob21venlnb3VzLCBib3RoIG9mIHRoZSBhbGxlbGVzIHRoYXQgdGhlIGluZGl2aWR1YWwgcG9zc2Vzc2VzIGhhcyB0byBiZSB0aGUgc2FtZS4gSW5kaXZpZHVhbCA0IGhhcyB0d28gZGlmZmVyZW50IGFsbGVsZXMgZm9yIGdlbmUgMyAoM2IgYW5kIDNjKS4gTmV4dCB0aW1lLCByZW1lbWJlciB0aGF0IHRoZSBwcmVmaXgg4oCYaG9tb+KAmSBtZWFucyDigJh0aGUgc2FtZSzigJkgd2hpbGUgdGhlIHByZWZpeCDigJhoZXRlcm/igJkgbWVhbnMg4oCYZGlmZmVyZW50LuKAmQ==[Qq]

[f]IENvcnJlY3QuIEluZGl2aWR1YWwgNCBoYXMgdHdvIGRpZmZlcmVudCBhbGxlbGVzIGZvciBnZW5lIDMgKGFsbGVsZXMgM2IgYW5kIDNjKSwgbWFraW5nIGhpbSBvciBoZXIgaGV0ZXJvenlnb3VzIGZvciB0aGF0IGdlbmUu

Cg==

[Qq]

[q topic = “alleles in populations”] The diagram below represents a gene pool for a population of five individuals with five genes. If we use the symbol ‘A’ to represent gene 1, which of the following makes sense as a representation of individual 2’s genotype for that gene?

[c]IEFB[Qq]

[c]IE Fh[Qq]

[c]IGFh[Qq]

[f]IE5vLiDigJhJbmRpdmlkdWFsIDIgaXMgaGV0ZXJvenlnb3RlIGZvciBnZW5lIDEgKGhlIG9yIHNoZSBoYXMgdHdvIGRpZmZlcmVudCBhbGxlbGVzKS4g4oCYQUHigJkgd291bGQgYmUgdGhlIGdlbm90eXBlIG9mIGFuIGluZGl2aWR1YWwgd2hvIHdhcyBob21venlnb3VzIGRvbWluYW50LiBUaGluayBvZiBhIHJlcHJlc2VudGF0aW9uIHRoYXQgd291bGQgc2hvdyB0aG9zZSB0d28gYWxsZWxlcyBhcyBiZWluZyBkaWZmZXJlbnQu[Qq]

[f]IENvcnJlY3QuIEluZGl2aWR1YWwgMiBoYXMgdHdvIGRpZmZlcmVudCBhbGxlbGVzIGZvciBnZW5lIDEuIFRoYXQgbWFrZXMgaGltIG9yIGhlciBhIGhldGVyb3p5Z290ZSwgYW5kIHlvdSB3b3VsZCByZXByZXNlbnQgdGhpcyBhcyDigJhBYS7igJk=[Qq]

[f]IE5vLiBJbmRpdmlkdWFsIDIgaXMgaGV0ZXJvenlnb3RlIGZvciBnZW5lIDEgKGhlIG9yIHNoZSBoYXMgdHdvIGRpZmZlcmVudCBhbGxlbGVzKS4g4oCYYWHigJkgd291bGQgYmUgdGhlIGdlbm90eXBlIG9mIGFuIGluZGl2aWR1YWwgd2hvIHdhcyBob21venlnb3VzIHJlY2Vzc2l2ZS4gVGhpbmsgb2YgYSByZXByZXNlbnRhdGlvbiB0aGF0IHdvdWxkIHNob3cgdGhvc2UgdHdvIGFsbGVsZXMgYXMgYmVpbmcgZGlmZmVyZW50Lg==

Cg==

[Qq]

[q topic = “alleles in populations”] The diagram below represents a gene pool for a population of five individuals with five genes. Is gene 5 a fixed allele?

[c]IFllcy4gR2VuZSA1IGlzIGEgZml4ZWQgYWxsZWxlLg==[Qq]

[c]IE5vLiBHZW5lIDUgaXMgTk9U IGEgZml4ZWQgYWxsZWxlLg==[Qq]

[f]IEluY29ycmVjdC4g4oCYRml4ZWTigJkgYWxsZWxlIG1lYW5zIHRoYXQgdGhlcmXigJlzIG9ubHkgb25lIGFsbGVsZSBpbiB0aGUgZW50aXJlIHBvcHVsYXRpb24gZm9yIHRoYXQgZ2VuZS4gSWYgeW91IGxvb2sgYXQgdGhlIOKAmGdlbmUgNeKAmSBjb2x1bW4sIHlvdSBjYW4gc2VlIHRoYXQgdGhlcmUgYXJlIFRXTyBhbGxlbGVzIChhbGxlbGVzIDVhIGFuZCA1Yiku[Qq]

[f]IENvcnJlY3QuIElmIHlvdSBsb29rIGF0IHRoZSDigJhnZW5lIDXigJkgY29sdW1uLCB5b3UgY2FuIHNlZSB0aGF0IHRoZXJlIGFyZSBUV08gYWxsZWxlcyAoYWxsZWxlcyA1YSBhbmQgNWIpLiBUaGVyZWZvcmUsIHRoZSBhbGxlbGUgaXMgbm90IGZpeGVkLg==

Cg==

[Qq]

[q topic = “alleles in populations”] The diagram below represents a gene pool for a population of five individuals with five genes. Is gene 2 a fixed allele?

[c]IFllcy4gR2VuZSAyIGlzIG EgZml4ZWQgYWxsZWxlLg==[Qq]

[c]IE5vLiBHZW5lIDIgaXMgTk9UIGEgZml4ZWQgYWxsZWxlLg==[Qq]

[f]IENvcnJlY3QuIOKAmEZpeGVk4oCZIGFsbGVsZSBtZWFucyB0aGF0IHRoZXJl4oCZcyBvbmx5IG9uZSBhbGxlbGUgaW4gdGhlIGVudGlyZSBwb3B1bGF0aW9uIGZvciB0aGF0IGdlbmUuIElmIHlvdSBsb29rIGF0IHRoZSDigJhnZW5lIDLigJkgY29sdW1uLCB5b3UgY2FuIHNlZSB0aGF0IHRoZXJlIGlzIG9ubHkgb25lIGFsbGVsZSwgbWFraW5nIGdlbmUgMiBhIGZpeGVkIGFsbGVsZS4=[Qq]

[f]IEluY29ycmVjdC4gSWYgeW91IGxvb2sgYXQgdGhlIOKAmGdlbmUgMiBjb2x1bW4sIHlvdSBjYW4gc2VlIHRoYXQgdGhlcmXigJlzIG9ubHkgb25lIGFsbGVsZSBpbiB0aGUgZW50aXJlIHBvcHVsYXRpb24gZm9yIHRoYXQgZ2VuZS4gSGF2aW5nIG9ubHkgb25lIGFsbGVsZSBpcyB0aGUgZGVmaW5pdGlvbiBvZiBmaXhlZCBhbGxlbGUuIFJlbWVtYmVyIHRoYXQgd2hlbiB5b3Ugc2VlIHRoaXMgcXVlc3Rpb24gYWdhaW4u

Cg==

[Qq]

[q topic = “alleles in populations”]A problem threatening cheetah survival is

[c]IGxvdyBmZX J0aWxpdHk=[Qq]

[c]wqBoaWdoIHNwZXJtIGNvdW50cw==[Qq]

[c]wqB0b28gbXVjaCB2YXJpYWJpbGl0eSBiZXR3ZWVuIG1lbWJlcnMgb2YgdGhlIHBvcHVsYXRpb24u[Qq]

[f]IENvcnJlY3QuIEEgcHJvYmxlbSBmYWNpbmcgY2hlZXRhaHMgaXMgdGhlaXIgbG93IGZlcnRpbGl0eSwgbWVhbmluZyB0aGVpciBpbnRyaW5zaWMgKGJ1aWx0LWluKSBkaWZmaWN1bHR5IHByb2R1Y2luZyB5b3VuZy4=[Qq]

[f]IE5vLsKgQ2hlZXRhaHMgYXJlIGZhY2luZyB0aGUgb3Bwb3NpdGUgcHJvYmxlbTogbG93IHNwZXJtIGNvdW50cy4gSW4gdGVybXMgb2YgdGhpcyBxdWVzdGlvbiwgd2hhdCB3b3VsZCBsb3cgc3Blcm0gY291bnRzIGxlYWQgdG8/[Qq]

[f]IE5vLsKgQ2hlZXRhaHMgYXJlIGZhY2luZyB0aGUgb3Bwb3NpdGUgcHJvYmxlbTogdGhlcmUgaXMgYWJub3JtYWxseSA=bG93IHZhcmlhYmlsaXR5IGFtb25nIGNoZWV0YWhzLg==

Cg==

[Qq]

[q topic = “alleles in populations”]Compared to other cat species, genetic variation among cheetahs is

[c]IGhpZ2hlcg==[Qq]

[c]wqBhYm91dCB0aGUgc2FtZQ==[Qq]

[c]IGxv d2Vy[Qq]

[f]wqBOby4gQ2hlZXRhaHMgYXJlIGZhY2luZyB0aGUgb3Bwb3NpdGUgcHJvYmxlbS7CoFRoYXQgbWVhbnMgdGhhdCB0aGVpciBnZW5ldGljIHZhcmlhdGlvbiB3b3VsZCBiZSYjODIzMDs=[Qq]

[f]IE5vLsKgQ2hlZXRhaHPCoHNlZW0gdG8gYmUgbXVjaCBtb3JlIHJlbGF0ZWQgdG8gb25lIGFub3RoZXIgdGhhbiBvdGhlciBzcGVjaWVzIG9mIHdpbGQgY2F0cy4gVGhhdCBtZWFucyB0aGF0IHRoZWlyIGdlbmV0aWMgdmFyaWF0aW9uIHdvdWxkIGJlJiM4MjMwOw==[Qq]

[f]IFllcy4gQ2hlZXRhaHMgaGF2ZSBtdWNoIGxvd2VyIGdlbmV0aWMgdmFyaWF0aW9uIHRoYXQgb3RoZXIgd2lsZCBjYXQgc3BlY2llcy4=

Cg==

[Qq]

[q topic = “alleles in populations”] Compared to other species of wild cats, you would expect cheetahs to have

[c]wqBmZXdlciBmaXhlZCBhbGxlbGVz[Qq]

[c]wqBtb3JlIGZpeG VkIGFsbGVsZXM=[Qq]

[c]wqBhYm91dCB0aGUgc2FtZSBudW1iZXIgb2YgZml4ZWQgYWxsZWxlcw==[Qq]

[f]wqBOby4gQ2hlZXRhaHMgaGF2ZSA=bG93IGdlbmV0aWMgZGl2ZXJzaXR5LsKgSWYgYSBwb3B1bGF0aW9uwqBoYXPCoGxvdyBnZW5ldGljIGRpdmVyc2l0eSwgaXQgd2lsbCBoYXZlIGZldyBoZXRlcm96eWdvdGVzLCBhbmQgX19fX18gZml4ZWQgYWxsZWxlcy4=[Qq]

[f]wqBZZXMuIENoZWV0YWhzIGhhdmUgbG93IGdlbmV0aWMgZGl2ZXJzaXR5LCBtZWFuaW5nIHRoYXQgdGhleSYjODIxNztsbCBoYXZlIA==bW9yZQ==IGZpeGVkIGFsbGVsZXMu[Qq]

[f]wqBOby4gQ2hlZXRhaHMgaGF2ZSA=bG93IGdlbmV0aWMgZGl2ZXJzaXR5LsKgSWYgYSBwb3B1bGF0aW9uwqBoYXPCoGxvdyBnZW5ldGljIGRpdmVyc2l0eSwgaXQgd2lsbCBoYXZlIGZldyBoZXRlcm96eWdvdGVzLCBhbmQgX19fX18gZml4ZWQgYWxsZWxlcy4=[Qq]

[x]

[restart]

[/qwiz]

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