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1) Australopithecines were the ancestors of modern humans. Select all of the phr

ID: 274806 • Letter: 1

Question

1) Australopithecines were the ancestors of modern humans. Select all of the phrases that accurately describe australopithecines.

Check All That Apply

Flat skull baseFlat skull base

Legs and arms shorter than modern humansLegs and arms shorter than modern humans

More human-like than chimp-likeMore human-like than chimp-like

Large teethLarge teeth

Large craniumLarge cranium

Walked like a humanWalked like a human

Stood 4-5 feet tall

2) Some traits that are uniquely human are due to changes in the sequence or expression of single genes. In each of the following examples, identify the genetic change involved.

1. Humans have less body hair than chimpanzees and gorillas due to loss of expression of  (Click to select)  the embryonic hemoglobin genes  a keratin gene  the fetal hemoglobin genes  the FOXP2 gene  .

2. The ability to speak is controlled by the  (Click to select)  MYH16  fetal hemoglobin  keratin  FOXP2  gene.

3. The human genome is not that different from that of a pufferfish, with added   (Click to select)  mitochondrial DNA  hemoglobin genes  introns  gene regulatory sequences  and repeated sequences.

4. Most of the differences between humans and chimpanzees are due to  (Click to select)  single nucleotide polymorphisms  changes in chromosome structure  changes in gene expression  changes in the genome sequence  .

3) The peopling of the world was a series of founder effects as groups left Africa. Select all of the sentences that accurately describe the peopling of the world.

Check All That Apply

Geographical and climatic barriers periodically shrank human populations.

Geographical and climatic barriers periodically shrank human populations.

Natural selection and genetic drift expanded the African gene pool.

Natural selection and genetic drift expanded the African gene pool.

Global climate change, such as ice ages, forced people into habitable areas, called refugia.

Global climate change, such as ice ages, forced people into habitable areas, called refugia.

Between 23,000 and 19,000 years ago, a population bottleneck killed off all but about only 1,000 people who had survived the journey over the bridge from Siberia.

Between 23,000 and 19,000 years ago, a population bottleneck killed off all but about only 1,000 people who had survived the journey over the bridge from Siberia.

Native American populations are very different from each other because of their journey across the land bridge.

Native American populations are very different from each other because of their journey across the land bridge.

The earliest Eskimos in Greenland came from a different migration than the one that was ancestral to Native Americans and modern Eskimos, and left no present-day descendants.


Explanation / Answer

1. Flat skull base

Legs and arms shorter than modern humans

Large teeth

Walked like a human

Stood 4-5ft tall

2. FOXP2 gene

3. gene regulatory sequence and repeated sequence

4. Single nucleotide polymorphisms

5. Geographical and climate barriers periodically shrank human population

Natural selection and genetic drift expanded the African gene pool

Global climate change such as ice ages forced people into habitable areas called refuges.