Question 1

How is nuclear DNA inherited?

Accepted Answer

Nuclear DNA inheritance follows the pattern of Mendelian inheritance, where 50 percent of each parent's nuclear DNA is inherited by their offspring. Therefore, 50 percent of nuclear DNA is inherited from the mother's ancestral line and 50 percent from the father's ancestral line.

Question 2

Which of the following statements is NOT true?

Accepted Answer

Different species of hominins actually coexisted on Earth, such as Homo sapiens and Homo neanderthalensis.

Question 3

In 2010, Dr. Svante Pääbo published research indicating that all modern ethnic groups, other than Africans, carry traces of Neanderthal DNA in their nuclear genomes. His earlier work indicated no overlap between Neanderthal mitochondrial DNA and that of Homo sapiens. Which of the following is NOT a likely possible hypothesis that could be supported by this information?

Accepted Answer

The lack of overlap in mitochondrial DNA (passed from mother to child) between Neanderthals and Homo sapiens suggests that if interbreeding occurred, it was not simply between female Neanderthals and male Homo sapiens, making option D not a likely hypothesis based on the given information.

Question 4

Is it possible for Homo sapiens and Neanderthals to be related even if humans are not the direct descendants of Neanderthals?

Accepted Answer

Humans and Neanderthals share a common ancestor as both species evolved from a common ancestor around 600,000 years ago. While humans are not direct descendants of Neanderthals, they share a significant amount of genetic material due to interbreeding. Therefore, it is possible for Homo sapiens and Neanderthals to be related even if humans are not the direct descendants of Neanderthals. Option A and B are incorrect as they suggest no connection or a linear evolution of humans, which is not scientifically accurate. Option C is partially correct as humans and Neanderthals did interbreed, but it does not fully explain the relationship between the two species.

Question 5

Would a hominin evolutionary tree look thin and spindly or full and bushy?

Accepted Answer

The hominin evolutionary tree would look full and bushy because it would have started about 6 mya with multiple branched branches throughout the millennia. This is because the hominin evolutionary history is characterized by multiple species, lineages, and transitions, resulting in a diverse and complex tree. While there is some debate about the exact branches of the tree and the relationships between different hominin species, it is generally accepted that the tree is full and bushy, with many divergent branches and multiple transitional forms.

Question 6

What evidence would support the hypothesis that Neanderthals evolved sometime after hominins migrated out of Africa?

Accepted Answer

The presence of Neanderthal DNA in the genomes of modern humans in all ethnic groups except for those of Africans suggests that interbreeding occurred between Neanderthals and modern humans after the latter migrated out of Africa but before the populations diverged. This supports the hypothesis that Neanderthals evolved later than the hominins that migrated out of Africa.

Question 7

Examine the skulls shown in this figure. What can be said regarding trends in braincase size and teeth over time?

Accepted Answer

The trend over time is towards larger braincase size and smaller, more humanlike teeth. This can be seen in the gradual reduction in teeth size and increase in braincase size from older hominin fossils to more recent ones.

Question 8

If evidence indicates that Homo erectus and Homo habilis used stone tools and may have been able to use fire, which of the following is also likely?

Accepted Answer

Homo heidelbergensis and Homo neanderthalensis are later hominid species that also used stone tools and are known to have used fire. The other species mentioned in the answer choices are too early in our evolutionary history to have evidence of fire use.

Question 9

Fossilized hominin bones have been found in Germany along with some tools and evidence of charred and fossilized bones from large animals dating to about 350,000 years ago. The hominin bones bear resemblance to both Homo erectus and Homo sapiens. Which of the following is the most likely possible identity of these fossils?

Accepted Answer

The fossils have similarities to both Homo erectus and Homo sapiens, suggesting they may be an example of archaic Homo sapiens. The other choices (Australopithecus anamensis, Homo habilis, and Paranthropus boisei) are all more ancient hominin species that would not be expected to have overlapped with evidence of tools and charred animal bones from 350,000 years ago.

Question 10

Which of the following best describes the source of your mitochondrial DNA?

Accepted Answer

Mitochondrial DNA is inherited maternally, meaning that all of an individual's mitochondrial DNA comes from their mother.

Question 11

You are evaluating DNA from a fossil and hypothesize that the mother was a Neanderthal and the father was a human. Which of the following would support your hypothesis?

Accepted Answer

The answer of You are evaluating DNA from a fossil...

Question 12

Which of the following best describes the source of your nuclear DNA?

Accepted Answer

Nuclear DNA is inherited from both parents through a process called sexual reproduction. This means that each parent contributes half of their genetic material to their offspring, resulting in a combination of genetic traits from both parents. Therefore, half of an individual's nuclear DNA comes from their mother and half comes from their father.

Question 13

Fossil evidence indicates that the first members of the genus Homo arose approximately ________ years ago.

Accepted Answer

Fossil evidence suggests that the first members of the genus Homo, including Homo habilis, arose approximately 2 million years ago. This was a significant development in human evolution, as it marked the emergence of early tool use and a larger brain size in our ancestors.

Question 14

The infamous American outlaw, Jesse Woodson James, died April 3, 1882. His body was originally interred on the James' farm but was later moved to Mt. Olivet Cemetery in Kearney, Nebraska. Some people have hypothesized that his death was staged. Researchers have exhumed the body and analyzed mitochondrial DNA found in the teeth with that of mitochondrial DNA from hair samples from the James' farm burial site; they matched. These samples were then compared to the mitochondrial DNA of Jesse's sister Susan's great-grandson and her great-great-grandson. Which of the following would support the hypothesis that the body buried in Mt. Olivet Cemetery is NOT Jesse James?

Accepted Answer

If the body buried in Mt. Olivet Cemetery is not Jesse James, then the mitochondrial DNA from the grave would not match the mitochondrial DNA obtained from Jesse's relatives. Therefore, the correct choice is B, as it states that the mitochondrial DNA from the grave does not match the mitochondrial DNA obtained from Susan's great-grandson and great-great-grandson, which would indicate that the body buried in Mt. Olivet Cemetery is not Jesse James.

Question 15

Eggs provide

Accepted Answer

The answer of Eggs provide
...

Question 16

How is mitochondrial DNA inherited?

Accepted Answer

Mitochondrial DNA is inherited only from the mother, as the sperm contributes very little (if any) mitochondrial DNA to the developing embryo. This is because all the mitochondria in a sperm's tail are destroyed during fertilization. Therefore, all children inherit their mitochondrial DNA exclusively from their mother.

Question 17

Evidence indicates that archaic Homo sapiens gave rise to which of the following?

Accepted Answer

Archaic Homo sapiens gave rise to both modern humans and Homo neanderthalensis, as evidenced by genetic studies and fossil evidence. Homo habilis and Homo rudolfensis are considered to be early members of the Homo genus, but they did not directly give rise to modern humans or Neanderthals.

Question 18

Sperm provide

Accepted Answer

Sperm provide only nuclear DNA to the offspring cell, while the egg provides both nuclear and mitochondrial DNA.

Question 19

If your mitochondrial DNA was sequenced and compared to the sequence of mitochondrial DNA isolated from your mother's paternal grandmother (the mother of your mom's dad) would you expect to see a significant match to yours and why?

Accepted Answer

Mitochondrial DNA follows a maternal inheritance pattern, meaning it is passed down from mother to her offspring. Therefore, there would not be a significant match between your mitochondrial DNA and your mother's paternal grandmother.

Question 20

Examine the following Hominin evolutionary tree. Which of the following genera are most closely related?

Accepted Answer

The genus Australopithecus and Homo are most closely related as they share a common ancestor more recently than any of the other genera on the tree.

Quiz 14: Human Evolution