BIO SOCIETY EXAM 2

Which of the following is an accurate statement regarding human evolution?

-In the latest phase of human evolution, there has been a greater reliance on culture. -The first humans evolved in Africa. -The fossil record contains creatures with features that are intermediate between those of modern humans and quadrupedal apes.

The discovery of the fossilized remains of Tiktaalik was important because this fossil represents _____.

-a transitional fossil -an intermediate between older similar aquatic fossils and newer similar terrestrial fossils -the movement of animals from aquatic environments to terrestrial environments

Which of the following traits can be used to differentiate humans from our closest living primate relatives?

-extensive tool use -large brain size -bipedality (the ability to walk exclusively on two legs

The first genetic material is thought to have been _____.

RNA

What observation concerning the geographic distribution of species on the Galápagos Islands helped Darwin formulate his ideas about the mechanisms of evolution?>

Darwin observed that most of the animals that inhabit these remote islands are not found anywhere else in the world, but they resemble South American species. Furthermore, each island has its own unique species.

Which statement is true about the origins of humans?

Human evolution likely occurred in Africa.

Scientists contend that humans and modern apes are related. What specifically does that mean?

If you traced the ancestry of humans and apes, you would at some point arrive at a shared ancestor that was neither a modern ape nor a human.

Homo neanderthalensis

Made sophisticated tools, controlled fire, had shelters, had "culture", skilled hunters.

Experiments in which electricity was discharged into a vessel containing hydrogen gas, water vapor, methane, and ammonia to simulate early-Earth chemistry were conducted by __________.

Miller and Urey

The absence of ______ in the primitive atmosphere was essential to the origin of life on Earth.

O2

Which of those listed is NOT an advantage of bipedalism?

Pelvic size that allowed for easier birth of large skulls

Why is RNA thought to have been the first genetic material?

RNA is capable of self-replication.

Remember that the protein hemoglobin is composed of many amino acids strung together. Most vertebrate carry genes for hemoglobin, however they are not all exactly the same and amino acid sequences will vary between groups. Which statement is true?

The more closely related organisms are, the more amino acids they have in common.

Louis and Mary Leakey found two different fossil hominid skulls at Olduvai. Which of the following statements about the skulls is true?

The second skull represented a species more closely related to modern humans than the first skull's species.

Australopithecusspecies

Walked upright regularly, short in stature, saw increases in brain size

Which of the following anatomical features of the 3.2-million-year-old Australopithecus fossil known as "Lucy" suggest she was a bipedal hominid?

a much shorter hip bone that is broader from front to back and wraps around the side

According to one of the main hypotheses for the origin of life, what must have come first?

abiotic synthesis of organic monomers

What was the first key hominid trait to appear in the fossil record?

bipedalism, as indicated by skeletal structure

What traits were present in early Homo habilis, the first representatives of the genus Homo?

bipedalism, moderate brain size, and tool use

How do scientists know that the hominid called "Ardi" is about 4.4 million years old?

by using radiometric dating techniques on the volcanic deposits found above and below the layer containing Ardi

A period of mass extinction is often followed by ________.

explosive diversification Submit

The genes that code for the RNA components of ribosomes are very, very similar to each other in all of the domain Eukarya. They are also very similar to the domains Bacteria and Archaea. These genes have not changed much over evolutionary time and as such, they are considered to be _____.

highly conserved genes

Currently, we humans are the only hominid species on Earth. This situation _____.

is relatively recent. For most of hominid history there were multiple coexisting hominid species.

Homo habilis

nicknamed "handy man" for their use of tools made from bone and rock.

Sahelanthropus tchadensis

oldest known member of "human"family tree, could walk upright when it needed to

Which anatomical features are homologous?

the forelimb of a dog and the forelimb of a cat

Humans have a tailbone even though we have no tail and therefore serves less of a function for our bodies. However, our evolutionary ancestors did have a tail. Our tailbones are considered to _____.

vestigial structures

It is hypothesized that the dinosaurs _____.

went extinct due to a meteor crash and the rapid environmental changes that occurred because of it

The first photosynthetic cells were thought to _____.

have evolved before the first aerobically respiring cells

Homo sapiens

modern day humans

Conditions on early Earth were not favorable to life. Describe these early Earth conditions. Select all that apply.

-no liquid water (oceans, lakes, rivers) -atmosphere lacking oxygen, containing nitrogen oxides, methane, ammonia, and hydrogen sulfide -frequent meteor and volcanic activity

About how many years ago did the lineages leading to chimpanzees and modern humans become separated?

5 million years

Which of the following statements about the classification of primates are true?

=Apes and monkeys are anthropoids. =Monkeys are primates and anthropoids. Submit

What did scientists learn from other fossils found in the same sediment layer as Ardi?

Ardi lived in a woodland habitat

Characid fishes are found naturally only in South America and Africa. Fossils of these fish are not found on any other continents. What is the most likely explanation of this distribution pattern?

Characid fishes arose prior to the separation of the African and South American continents.

The Miller-Urey experiment mimicked life on early Earth. What did they discover with their experiment?

Conditions on early Earth favored the creation of small molecules needed for life, including amino acids

What does the primate phylogenetic tree show?

All primates descended from a common ancestor.

Which of the following statements supports the conclusion that the common ancestor of modern chimps and modern humans lived around 7 million years ago?

Analysis of modern human and modern chimpanzee protein and DNA sequences suggests that their lineages diverged about 7 million years ago.

The similarity of the embryos of chickens and humans is evidence of ________.

common ancestry