General Biology - FINAL Exam (Ch. 15 and 19)

Bacterial conjugation is the process in which a bacterium

B. exchanges DNA directly with another bacterium.

Which of the following groups of characteristics defines prokaryotes?

C. single-celled, single circular chromosome, no membrane-enclosed organelles

Mosquito-borne diseases include

A. Dengue B. Malaria C. Yellow fever D. West Nile E. Chikungunya F. Zika Correct Answer: G. All the above

If a professional scientist is trying to build an extensive database of bacterial swabs from humans in all parts of the world, what is the most cost-effective way to increase the number of samples collected in a one-year time period?

A. Train citizens of many countries to collect samples from people in their local area.

The human microbiome is the complete collection of microbes that live in and on our cells and bodies.

A. True

Which of the following is true of the Zika virus?

A. Zika is spread by females of both the Aedes aegypti and Aedes albopictus species. B. Zika is a DNA virus. C. Infected mothers pass the Zika virus to their fetuses. D. Zika causes a birth defect called microcephaly (stunted brain growth). E. All the above is true Correct Answer: F. Only A, C, and D are true

What is a possible result of a rapid increase in population density?

A. a lack of food to support the sudden increase in individuals B. an increase in behaviors not adapted to life in community C. an increase in death due to increase in disease Correct Answer: D. all the above

An individual with a deep, closed belly button is more likely to have more __________ bacteria living in his or her belly button compared to an individual with a shallow, open belly button.

A. anaerobic

Which of the following are most well known for their ability to thrive in extreme environments that feature extremely high temperatures, high salt concentrations, or very acidic conditions?

A. archaeans

14. Some prokaryotes can

A. break down chemicals for energy. B. use sunlight for energy. C. create their own energy. D. harvest energy from other organisms. Correct Answer: E. all the above

Archaeans are often referred to as "extremophiles" because they are

A. capable of living in extreme environments where other organisms cannot function.

The maximum number of individuals in a population that can be supported indefinitely by the population's environment is called the

A. carrying capacity.

If a population is growing with no constraints on its resources, it will

A. grow exponentially.

The human microbiome affects

A. gut and brain health B. body odor C. risk of infection D. how attractive you are to other people or mosquitos Correct Answer: E. all the above

The growth of populations can be limited by

A. natural disturbances. B. weather. C. food shortages. Correct Answer: D. All the above

Disease-causing bacteria in a human begin to multiply rapidly when they sense that their numbers are high enough to overpower an immune response. This is possible because of

A. quorum sensing.

Structures produced by bacteria, but not archaeans, that are extremely resistant to boiling and freezing temperatures are

A. spores.

Many bacteria have a shorter generation time at warmer temperatures. Why do food safety guidelines recommend rapidly cooling leftover foods and maintaining them at refrigerator temperatures?

B. Many bacteria reach disease-causing levels rapidly when food is warm.

Prokaryotes can be found in most habitats because they

B. can survive in both oxygen-rich and oxygen-free environments.

A prokaryotic cell and a eukaryotic cell are placed in an environment ideal for growth of both cells. After 24 hours it is observed that the prokaryote cell population is significantly greater than the eukaryote cell population. This has occurred because prokaryotes

B. have a simpler structure, which allows more rapid reproduction.

Prokaryotes may pick up pieces of DNA from the environment or other bacteria and incorporate these pieces into their own genome through

B. horizontal gene transfer.

Professional scientists benefit from citizen science because citizens

B. increase their ability to collect samples.

Heterotrophic bacteria and archaeans that are decomposers are important in

B. nutrient cycling.

If one forgets to brush his or her teeth, bacteria may use __________ to attach onto the surface of the teeth.

B. pili

One of the earliest prokaryotes on Earth, the cyanobacteria, played an important role in the evolution of multicellular eukaryotes. These early prokaryotes changed Earth's chemistry when they began

B. producing oxygen as a by-product of photosynthesis.

When a population reaches its carrying capacity,

B. the birthrate = the death rate.

Is it reasonable to expect that all habitats suitable for a given organism will have the same carrying capacity for that organism?

C. No; an organism may be able to live in many locations, but the resources it requires may be available in varying amounts.

Prokaryotes that are observed "swimming" through a liquid environment most likely possess

C. a flagellum.

A disease-causing bacterium may be protected from the immune system by a slippery

C. capsule.

Escherichia coli, a bacterium that normally lives in the gut of humans, will have the shortest generation time when it is found

C. in an incubator set close to human body temperature.

A group of individuals of a single species located within a particular area is called

D. a population.

Cells that lack membrane-enclosed organelles and have a single circular chromosome may be

D. either bacteria or archaea.

Bacteria and archaea are both classified as

D. prokaryotes.

Match each prokaryotic cell structure with its description: A. capsule B. pilus C. flagellum D. cell wall E. plasmid

E. Plasmid: loop of non-chromosomal DNA A. Capsule: helps protect disease-causing bacteria from destruction by the immune system C. Flagellum: spins like a propeller to allow movement through a liquid environment B. Pilus: links bacteria together or attaches them to a surface in their environment D. Cell Wall: surrounds the cell, just outside of the plasma membrane