OSU BIO 1101 Exam 4

What is the characteristic of bacteria in terms of cell structure?

Bacteria are prokaryotic cells.

How do bacteria reproduce?

Bacteria reproduce by binary fission.

What unique component do bacterial cell walls contain?

Peptidoglycan.

What is the shape of bacterial chromosomes?

Circular.

What is MRSA?

A bacterial infection that can become resistant to treatment.

How are bacteria classified?

By shape, gram stain, and habitat.

What are the two types of bacterial toxins?

Endotoxins and exotoxins.

What is an endospore?

A specialized bacterial cell structure that can withstand extreme conditions.

What is the function of peptidoglycan?

It provides strength to the bacterial cell wall.

What are viruses considered in terms of cellular structure?

Non-cellular infectious agents.

What are the two basic components of a virus?

DNA or RNA as a genetic core and a tough protein coat/capsule.

What is the first step in the viral infection process?

Viral attachment to the host cell.

What happens during viral penetration?

Viral genetic material enters the host cell.

What is the role of reverse transcriptase in HIV?

It converts RNA into DNA.

What is antigenic drift?

A process where the flu virus mutates slightly during replication.

What is antigenic shift?

A process that creates a new strain of virus when an organism is infected with multiple flu viruses.

What is the average number of deaths caused by influenza in the U.S. per year?

Approximately 20,000 deaths.

What was the cause of the 1918 pandemic known as the Spanish Flu?

An RNA virus called influenza.

What is botulism?

A type of food poisoning caused by an exotoxin from clostridium botulinum.

What does Botox do?

It acts as a neurotoxin that kills part of a nerve cell.

What is the primary habitat for the West Nile virus?

Cycles between mosquitoes and birds.

What is the significance of the bacterium Bacillus anthracis?

It is known for its endospore formation and can cause anthrax.

What is the effect of antibiotics on peptidoglycan?

Many antibiotics target peptidoglycan to stop bacterial growth.

What is the typical reproduction rate of bacteria under ideal conditions?

Every 20 minutes.

What is the primary method of viral release from host cells?

Budding or lysis.

What is the primary tissue affected by the influenza virus in humans?

Lungs.

What is the difference between endotoxins and exotoxins?

Endotoxins are part of the bacterial cell wall, while exotoxins are secreted by bacteria.

How does the immune system respond to nerve cells infected by herpes?

The immune system does not kill nerve cells, leading to permanent infection.

What is the primary reason for getting flu shots every year?

Antigenic drift and shift due to changes in the virus.

What are the two types of antigenic changes that occur in viruses?

Antigenic drift and antigenic shift.

What does H5N1 or H1N1 refer to?

Sub-types of the influenza virus that the body may not recognize.

What is the role of swine in the transmission of influenza viruses?

Swine can be co-infected with human and bird viruses, which can then infect humans.

Why is hand washing important in preventing influenza?

It helps deactivate the virus by breaking apart the lipid component of its envelope.

What is the most common virus that causes the common cold?

Rhinovirus, responsible for about 50% of cases.

How do cold viruses primarily spread?

By direct contact to the nose.

What is a common myth about catching colds?

That wet hair or not wearing a coat in winter causes colds.

What are prions?

Pathogenic proteins that can influence other proteins to change configurations.

Who proposed the idea that pathogenic proteins can influence other proteins?

John Stanley Griffith.

What disease is caused by prions in cows?

Mad Cow Disease.

What is Chronic Wasting Disease?

A prion disease in deer and elk that causes them to stop eating and wither away.

What happens to nerve tissue in Spongiform Encephalopathies?

It becomes spongy and loses motor functions due to prion proteins.

What is the significance of Stanley B. Prusiner's work?

He won the Nobel Prize for demonstrating that prions are infectious proteins.

What is the impact of sneezing on the spread of cold viruses?

Particles can travel 2-3 meters at speeds of 150 km/hr, effectively spreading the virus.

What is abiogenesis?

The beginning of life, marking the transition from non-life to life.

What are the three distinct subjects often confused with evolution?

Abiogenesis, evolution, and speciation.

What is the main confusion surrounding the term 'evolution'?

It is often misused in contexts outside of biological evolution.

What is the effect of prions on proteins?

One prion can influence other proteins to misfold, creating more prions.

What is the primary method of prion transmission?

Through body fluids or consumption of infected tissue.

What is a key characteristic of prions in terms of disinfection?

Normal disinfectant methods are ineffective against prions.

What is the consequence of prion infection in humans?

It can lead to diseases such as Creutzfeldt-Jakob Disease (CJD), which is permanent and deadly.

What is the estimated age of the Earth?

4.6 billion years

How old are the oldest rocks containing life forms?

3.5 billion years

What does organic 'biological' evolution deal with?

Living organisms

How far back does the idea of evolution date?

At least 3,500 years ago (500-600 BCE)

Who developed the idea of inheritance of acquired characters?

Jean-Baptiste de Lamarck

What was Malthus's contribution to the understanding of populations?

He documented that populations rapidly increased in numbers.

What is spontaneous generation?

The idea that complex living organisms arise spontaneously from non-living materials.

Who disproved spontaneous generation?

Louis Pasteur

What is the hypothesis proposed by Louis Pasteur?

Cells arise from cells; they do not arise by spontaneous generation.

What mechanism drives evolution according to Darwin?

Natural selection

Who are the two individuals credited with the theory of natural selection?

Charles Darwin and Alfred Wallace

What is the title of Darwin's book published in 1859?

The Origin of Species

What does 'survival of the fittest' mean in evolutionary terms?

It refers to individuals best adapted to their environment who survive and leave offspring.

What is the significance of genetic variation in a population?

It allows for individuals to survive and reproduce in changing environments.

What is artificial selection?

Restricting mating to individuals with desired characteristics.

What is directional selection?

A shift in allele frequencies in a single constant direction due to environmental impacts.

What is an example of directional selection?

Pesticide resistance and antibiotic resistance.

What happens to individuals that are 'selected against'?

They are less likely to survive and reproduce.

How does natural selection affect allele combinations over time?

Traits that allow for survival and reproduction become more common in the population.

What is the result of individuals being 'selected for'?

They are better adapted to their environment and more capable of surviving to reproductive age.

What is the role of competition in natural selection?

It arises from limited resources, leading to a struggle for survival.

What does evolutionary 'fitness' refer to?

The ability to leave offspring.