Bio100 Pre-lecs second exam

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

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

Which of the following is not a characteristic of living things?

creating energy

Binary fission produces __________.

two genetically identical bacterial cells

The introduction of smallpox to the Americas by Europeans in the colonial era devastated populations of Native Americans. However, now very few people are vaccinated against the smallpox virus. Why?

Smallpox virus has been eliminated from the earth by vaccination of most of the people alive today.

Which eukaryotic structures are thought to have been the result of extensive inward folding of the plasma membrane of an ancestral prokaryotic cell?

The endoplasmic reticulum Prokaryotes do not have an extensive internal membrane system. Scientists believe that the interconnected internal membrane system of eukaryotes—including the endoplasmic reticulum, the nuclear envelope, and the Golgi apparatus—arose through the inward folding of the plasma membrane of an ancestral cell.

There are many organs and glands of the endocrine system, but which one is the master controller?

The hypothalamus

Why is combination drug therapy for HIV/AIDS less likely to lead to resistance than single drug therapy?

The likelihood of one virus spontaneously mutating to be resistant to several different drugs at the same time is extremely small.

What is radiometric dating?

The process of determining the age of a fossil from radioactive isotopes

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.

What is the concern about using antibacterial and antimicrobial soaps?

The use of any chemical that kills bacteria can eventually lead to resistance to that chemical in the population of bacteria

The urinary tract represents a portal of entry for E.coli, a normal inhabitant of the GI tract. Introduction of this opportunistic pathogen and its subsequent colonization is known as __________.

an infection An infection represents an invasion or colonization by a pathogen.

Female fireflies choose mates based on the specific flash pattern displayed by males flying nearby. This is an example of

behavioral isolation

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

The protein coat that surrounds the nucleic acid of a virus is called a

capsid

The protein coat that surrounds the nucleic acid of a virus is called a --

caspid

In the video, what does the UK's Chief Medical Officer suggest for promoting the development of new antibiotics?

encouraging big pharmaceutical companies to start investing again in new drug research and development

The evolution of populations due to chance is

genetic drift (Genetic drift describes the evolution of a population due to chance.)

In a population with brown and green alleles for color, genetic drift

has more effect on the evolution of a small population. (Genetic drift affects the evolution of small populations more than it affects the evolution of large populations.)

Sort each type of bacteria according to whether it is helpful or harmful.

helpful: probiotics nitrogen fibers decomposers Harmful: Salmonella MRSA pathogens

A degenerative brain disorder transmitted by cannibalism is called ________.

kuru

a viral life cycle in which the virus inserts its genome into the genome of its host, where it may remain dormant for long periods.

lysogenic cycle

a viral life cycle that results in bursting of the host cell.

lytic cycle

The process that gives rise to new species is called

speciation

Which of the following examples uses the biological species concept to describe different species

Female horses and male donkeys are able to mate, but their offspring (mules) are infertile.

Two populations of lobsters do not mate because one population lives in the Atlantic Ocean and the other lives in the Pacific Ocean.

Habitat isolation

The earliest hominin to use fire was

Homo erectus

A patient enters your office, feeling achy and tired. Subsequent evaluation reveals a temperature of 39.9 oC. The achy and tired feeling represents a _____ of infection, and that temperature represents a _____ of infection.

symptom; sign The feelings of achiness and tiredness are not measurable and are felt only by the infected individual. This represents a symptom of infection. Signs of infection are observable and/or measurable, and they tend to be more specific than symptoms.

Which of the following contributes the LEAST to the problem of antibiotic resistance

taking the entire course of antibiotics as prescribed by the doctor

Some researchers have proposed that the human population was reduced to fewer than 10,000 individuals as a result of a catastrophic event that occurred about 50,000 years ago, and that all modern humans are descendants of this small population. If this proposal is true, it would be an example of

the bottleneck effect

If color is an inherited trait in beetles, and birds are more likely to eat brown beetles than green beetles,

the frequency of the green allele will increase (If birds are more likely to eat brown beetles than green beetles, then green beetles will survive and reproduce more than brown beetles. This causes the frequency of the green allele to increase.)

Following an injury to your hand, the injured area appears red and swollen. It feels painful and warm to the touch. What is the cause of these symptoms

the inflammatory response

Although generally not considered to be alive, a -- is studied alongside other microbes such as bacteria.

virus

a virus that specifically infects bacteria.

bacteriophage

In the projected video showing the growth of bacteria, why did the bacteria grow up to the edge of the area with antibiotics, pause, then continue to grow across the area with antibiotics?

A few bacteria experienced random mutations in their DNA, which allowed some of them to grow even though antibiotics were present.

Which of the following pathogens causes mad cow disease?

A prion

What is the condition in which the body's immune system overreacts to an otherwise harmless foreign particle?

Allergy

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.

Which of the following do not get infected by viruses

Animals, plants and bacteria can all be infected by viruses.

Which of the following correctly describes what the video referred to as a "microbial cure"

Antibiotics are used to kill all of the infectious bacteria in a person.

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

Ardi lived in a woodland habitat

Over time, bacteria have become increasingly resistant to antibiotics. Which of the following best explains this in terms of natural selection?

Bacteria that happen to have natural resistance to antibiotics survived and reproduced.

By what means do prokaryotes typically divide?

Binary fission

Which of the following best defines microevolution?

Changes in genes within a population over time

Which period of infection represents the immune system or pharmaceutical intervention working at its peak performance? A-B-C-D-E? (shape is in a upside down U curve)

D The number of microbes is steadily decreasing due to the activity of the immune system or pharmaceutical intervention. As a result, the signs and symptoms associated with the infection are also dissipating.

In the lab, Nachman examined dark mice from two different populations living hundreds of km apart. The mice looked nearly identical. Their dark color was caused by two different genes. What does this tell you?

Dark fur color evolved independently on each lava flow. There are at least two genes involved in creating dark mouse fur. Two completely different mutations in two separate genes can generate the same phenotype. Under very similar conditions, natural selection can favor very similar adaptations

Many populations of clams release their sperm and eggs into the same region of a lake, but only the sperm and eggs from the same species successfully unite to form zygotes.

Gametic isolation

Color is an inherited trait in beetles. If brown beetles move into a population from a nearby island, which of the following statements is correct?

Gene flow causes the frequency of the brown allele to increase. (Gene flow occurs when individuals move into or out of a population, changing the allele frequencies in the population. In this case, new brown beetles in the population cause the frequency of the brown allele to increase.)

Habitat loss has driven the population of the Florida panther (Puma concolor cougar) to extremely low numbers. Which mechanism of microevolution is likely at play in this species?

Genetic drift: the bottleneck effect A drastic reduction in the population size has led to a much-reduced gene pool.

Remember that color is an inherited trait in beetles. Which of the following is an example of natural selection?

Green beetles leave more offspring than brown beetles because they are better at finding food. Natural selection occurs when organisms with one inherited trait survive and reproduce more than organisms with other trait

Patients with advanced AIDS often die from infections that do little harm to healthy people. Why?

HIV infects and destroys the helper T cells of the immune system.

When dark-colored fur gives mice a 1% competitive advantage and 1% of the population begins with dark fur, in about 1000 years, 95% of the population will have dark fur. Which of the following statements is true?

If dark-colored rock pocket mice had a competitive advantage of 0.1%, it would take longer for 95% of the population to have dark fur.

How might global warming result in most grizzly bears having fur that is less dense in the future?

In any population of bears, some individuals have thick fur, some have thin fur, and some are in between. As temperatures increase with the passage of time, the survival of bears with thin fur will increase, and the number of bears in the population with thick fur will decrease.

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 fossil record contains creatures with features that are intermediate between those of modern humans and quadrupedal apes. The first humans evolved in Africa.

The birds-of-paradise are a group of brightly colored birds living mostly in New Guinea that have elaborate and elongated feathers. Behavioral isolation prevents different birds-of-paradise species from mating and reproducing.

Males of one species perform orchestrated dances and sing songs that only attract females of the same species.

Which of the following are examples of macroevolution

Mass extinctions that wipe 50% or more of living species The creation of new species The evolution of novel biological features

A male snail and a female snail from different species attempt to mate, but the orientation of their different types of shells prevents mating from occurring.

Mechanical isolation

How do vaccines convey long-term immunity to some pathogens?

Memory cells

What does Dr. Carroll mean when he says, "while mutation is random, natural selection is not"?

Natural selection acts on traits. Mutations for advantageous traits are more likely to be passed on to the next generation. Natural selection favors some mutations.

A particular antibiotic kills 99% of a bacterial population. What will be the result of the continued application of this antibiotic?

Over time, the antibiotic will become less effective at killing the bacteria.

Two populations of flowers do not produce offspring because one blooms during early spring and the other blooms during late spring.

Temporal isolation

In addition to behavioral isolation, other reproductive barriers that may prevent populations from breeding and producing fertile offspring include:

Temporal isolation (mating or fertilization occurs at different seasons or times of day) Habitat isolation (populations live in different habitats and do not meet) Mechanical isolation (structural differences prevent fertilization) Gametic isolation (female and male gametes fail to unite in fertilization)

Although most biologists do not consider viruses to be alive, viruses do share some characteristics with living things. Which of the following is the requirement for life that viruses lack?

The ability to reproduce on their own

defines a species as a group of populations whose members have the potential to interbreed with one another and produce fertile offspring

The biological species concept

Which of the following statements about viruses is false ?

The widespread use of antibiotics has led to resistant strains of viruses.

Why do dark-colored rock pocket mice on dark lava flows have white bellies?

There is no selection for dark bellies by visual predators.

Why did dark-colored rock pocket mice first appear in a population of light-colored rock pocket mice?

They have a genetic mutation that affects their fur color.

Which medication prevents viral infections by priming the immune system against a specific virus?

Vaccine

Which of the following can be found in bacteria but not viruses?

a cell membrane

Mutations are always __________.

a change in an individual's DNA

A requirement of cladistics is that a grouping must include

a common ancestor and all its descendants

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

Suppose you were in charge of sending an unmanned space probe to a new planet in search of life. The probe would be able to collect and test samples and make observations, but the planet is too far away for the probe to be able to bring samples back to Earth. The probe is small and would only be able to run a few tests, so you want to pick a test for evidence of life that is broad enough to incorporate all forms of life as we know it. Which one of the following tests would be the best to use in this situation?

a test for the presence of cells that contain DNA

Homeostasis is a living organism's

ability to maintain constant internal conditions even when environmental conditions change.

Viruses are

not alive because they are not made of cells and require a host cell for reproduction.

In the Grand Canyon, fossils in rock layers at the bottom of the canyon are __________ than those in layers closer to the top.

older

A group of individuals of the same species that live in the same area and interact with one another is a

population

a viral genome that has inserted itself into the genome of its host.

prophage

anything that prevents successful interbreeding between species.

reproductive barrier

Which of these sub-cellular structures is found in both eukaryotes and prokaryotes?

ribosomes