Chapter 24 study review Bio

There is a phenomenon called parental leakage, in which a small amount of the mitochondrial DNA from the father is found in the offspring. If parental leakage is assumed to occur in most matings, how would it change our interpretation of studies of mitochondrial DNA in human ancestors and in groups of different modern humans?

If it is truly a small amount, then those deviations shouldn't influence the conclusions generated from the study

The first DNA comparison studies between humans and chimpanzees relied on which of the following?

The more complementary two strands of DNA are, the higher the melting point.

Which of the following statements about great apes is correct?

Bonobos are more closely related to humans than to orangutans.

Imagine that one of your friends has just learned about the multiregional hypothesis, and she is astonished that humans evolved independently (on different continents). What evidence would you provide your friend that contradicts the multi regional hypothesis?

Caan's research using mitochondrial DNA demonstrated that humans originated in Africa, and subsequently migrated to other continents.

is the name of a gene that may be important to language, as mutations in this gene are implicated in speech pathologies.

FOXP2

All evidence suggests that the Neanderthals did not interbreed with our ancestors.

False

Charles Darwin noted that the human lineage probably arose out of Africa. Which of the following was most likely the reason behind his hypothesis?

Gorillas and chimpanzees, which are the primates most closely related to humans, only live in Africa.

Which of the following hominin lineages is correct?

Homo ergaster → Homo heidelbergensis → Homo sapiens

The mitochondrial DNA study indicated that there was no genetic input from Neanderthals in modern humans, but the whole-genome study suggests that in fact there was. Which of the following strategies could be employed to resolve this discrepancy?

Look at the Y chromosome because that also does not undergo recombination.

There are seemingly conflicting studies that have taken a look at whether Neanderthals interbred with human ancestors. One study of mitochondrial DNA suggests that the two groups did not interbreed. Another study, of the whole genome, suggests that they did. Which of the following could explain these results?

Mitochondrial DNA is passed on the maternal side, so if Neanderthal females did not interbreed with our ancestors, Neanderthal mitochondrial DNA would never have entered the modern human gene pool.

Many researchers hypothesize that modern humans have derived from the Homo ergaster populations that spread around the world starting about 2 million years ago. This hypothesis is known as the:

Multi regional hypothesis

Which of the following characteristics separates primates from other mammals?

Primates have nails instead of claws.

Which of the following is the most likely explanation for why the human brain is capable of so much more than what would be required for evolutionary fitness?

The additional capabilities are by-products of what was necessary for evolutionary fitness.

Which one of the following is an advantage of using the fossil record to obtain information about our evolutionary history?

The fossil record gives us examples of the intermediate stages of evolution

Which of the following explains how chimpanzees and humans can be so different with such similar genomes?

The genetic differences could have occurred in genes responsible for development.

Which of the following hypotheses is the most current and accepted one with regard to modern human origins?

The out of Africa Hypothesis

There is some debate about whether Homo floresiensis is a separate species or an aberrant form of Homo sapiens. Regardless, what we do know is that H. floresiensis were only found on an Indonesian island and adults were only 3 feet tall. What could explain this distinct phenotype?

The smaller body size was necessary for an island, as food is often limited.

Cro-Magnon is the name of the group of the first Neanderthals found in Europe.

True

Hominins refers to members of all the different species in the lineage leading to humans.

True

Phenotypic differences between humans and chimpanzees may be better explained by the time during development when genes are turned on in humans and chimpanzees, than by genetic differences themselves.

True

When Rebecca Cann decided to research on the evolution of humans, she chose to study mitochondrial DNA. Which of the following explains why she chose this type of DNA?

because mitochondrial DNA is more abundant and therefore easier to extract

A young student is trying to figure out the order in which certain traits evolved in humans. Which of the arrangements below is most likely correct?

bipedalism → opposable thumbs → human jaw → language

Humans are included in which of the following groups?

great apes

You are working in a lab and come across a gene, Gene X, that you think might explain some of the differences seen between chimpanzees and humans. Which of the following results would support your hypothesis?

if Gene X was active in humans, juvenile chimpanzees and inactive in adult chimpanzees

Which of the following, if true, would force us to reevaluate the findings that Cann discovered with regard to the human family tree?

if human fossils were discovered in Asia that had DNA completely different from the DNA found in early Homo sapiens in Africa

Cann's studies involving mitochondrial DNA showed that the two deepest branches of the human family tree are African. Which of the following observations explains this statement?

that all humans evolved in Africa and only later migrated to other places

What does it mean when it is said that the tree of human evolution is shallow?

that all humans, no matter how distantly related they are, share a recent common ancestor

he common phrase "Humans evolved from chimpanzees" really means:

that humans and chimpanzees share a common ancestor.

What does it mean to say that humans are neotenous?

that humans in their adult state resemble juvenile chimpanzees

Analyzing DNA sequences in different populations provided us with what new information?

that the chimpanzees are more closely related to humans than gorillas are

Mitochondrial DNA studies were used to determine that Homo sapiens evolved in Africa and only later did they become established elsewhere.

true