Back-to-School: Genetics 101 Quiz Results

Okay students, pencils down!

A week ago Friday we posted the second in a three-part series of educational courses for back-to-school season. The entries are now in. You can see how you did by comparing with the correct answers below. Also, a special congratulations goes out to Damien Marsic for being selected among all the entries. For the rest of you, you’ll have more chances to win an Amazon gift card when we post the last quiz in our series. For those who love learning for the sake of learning, the course is still available here.

Question: Approximately how genetically similar are humans to each other?
Correct Answer: 99.5%
It’s amazing that just 0.5% difference still results in so much genetic variation amongst humans!

Question: There are rules for how the bases of DNA pair together. Which is correct?

(1) A pairs with A, C pairs with C, G pairs with G, T pairs with T
(2) A pairs with G and C pairs with T
(3) A pairs with C and G pairs with T
(4) A pairs with T and C pairs with G

Correct Answer: A pairs with T and C pairs with G

Question: How many total chromosomes do humans typically have?
Correct Answer: 46
Humans typically have 23 pairs of chromosomes for a total of 46 chromosomes.

Question: What inheritance laws did Gregor Mendel characterize?
Correct Answer: recessive and dominant
Gregor Mendel characterized the idea of recessive and dominant traits. Although other modes of inheritance also exist, Mendel’s experiments laid the groundwork for understanding how a genetic trait is passed to offspring.

Question: Gregor Mendel carried out his famous genetic experiments with:

(1) Cats
(2) Apples
(3) Monkeys
(4) Peas

Correct Answer: Peas!
Mendel chose the common garden pea for his first experiments. The pea was good choice because there are different varieties that produce easily distinguishable traits like seed texture (round or wrinkled), flower color (purple or white), seed color (green or yellow), and growth form (tall or short). He could also pollinate them himself.

Question: How many total chromosomes do chickens typically have?
Correct Answer: 78
Chickens have 39 pairs of chromosomes for a total of 78 chromosomes. Interesting fact – although chickens have more chromosomes than humans, they have roughly the same number of genes as humans.

Question: Roughly how many genes do humans have?
Correct Answer: 20,000
Humans have approximately 20,000 genes.