BIOS1063 Exam 1

correct order to represent the stages in which antigens are formed by the immune system.

1. a pathogen is detected in the immune system 2. the pathogen is ingested by the macrophage and is fragmented into pieces 3. a fragment of the pathogen called an antigen is attached to the surface of the macrophage 4. The expression of this antigen on the macrophage, which is now called an antigen-presenting cell, alerts the remainder of the immune system.

The influenza name A/Singapore/INFIMH-16-0019/2016 A(H3N2)-like virus, indicated that is the ______ form of the virus.

A

Which of the following best describes a virus?

A nonliving complex of RNA or DNA protected by a protein coat

occurs when two different influenza viruses infect the same host cell, and a new form of the virus is manufactured.

Antigenic shift

What is the correct sequence of events in viral reproduction?

Attachment, penetration, biosynthesis, maturation and release

Directional selection:

Changes in the environment direct natural selection to favor the variants at one end of the distribution.

Darwin also proposed that natural selection occurs is a series of steps:

Individuals vary in their traits. Individuals struggle to exist. Individuals differ in their fitness. Populations become adapted to the environment.

Cytokines are responsible for many of the symptoms we have when we get infected by a virus or bacteria

Redness Swelling Fever Body aches Nausea

Which protein structures on the SARS-CoV2 virus identify host cells?

S (spike proteins)

What are the stages of COVID

Three phases: Asymptomatic phase The virus incubates in the body 4-5 days Pulmonary phase 80% of people infected start to see symptoms as the immune system actives in the lungs Hyperinflammation phase Some individuals develop acute respiratory distress syndrome (ARDS) due to cytokine storm Results in low oxygen levels

Georges Cuvier

Zoologist who studied the fossil record and noticed that it showed a succession of different forms of life over time. However, he believed that all species were created at the same time, and that catastrophic events had caused some to go extinct.

All viruses are made up of two components. These components are

a protein capsid and genetic material.

Line of evidence 1, ______, is the comparison of physical structures between species.

anatomical evidence

_____________shared between organisms, whether visible as an adult or only visible during embryonic development, can indicate a trait has been inherited from a common ancestor, and the organisms have_________

anatomical features; shared evolutionary ancestry

certain types of influenza virus originate in

animals such as birds

the second form of adaptive immunity is often referred to as

antibody- mediated immunity

harmful mutations

can lead the protein to be nonfunctional

Each protein has its specific function in the

cell

evolution is

change over time

anti genetic drift causes the more

changes and strains in the influenza virus

the symptoms of the flu in humans is

cough, sore throat, problems breathing, nausea, body aches, fever, vomiting

natural killer cells

destroy cells of the body that have been infected by viruses or bacteria and the are nonspecific about what pathogens they destroy

Influenza viruses enter the respiratory system through

either the nose or mouth

Line of evidence 4, _______, focuses on embryo comparisons because some features may be present in the embryo that are not apparent in the adult form.

embryotic evidence

Over many generations, natural selection leads to_________ an explanation for the process of how organisms change over time.

evolution

_________ is supported by __________ evidence from all branches of biology, and scientists continue to test, evaluate, and refine their understanding of how evolution impacts life. Below are the different lines of evidence.

evolution; experimental

The exchange of genetic material allows the influenza virus to

evolve into a new form.

If two or more species share a unique physical feature, such as a similar___________ hey may have inherited this feature from a common ancestor. Physical features shared due to evolutionary history are said to be ___________

forelimb structure, homologues

Evidence of long-term evolutionary change starts with the ________ which provides evidence for the past existence of species that are now extinct. Although it is __________ record of evolutionary history, it not only provides evidence of what organisms were like but also gives an indication of how they evolved over time.

fossil record; not a complete

The virus can now be transmitted to a new host, such as humans, and spread easily

from person to person causing a flu outbreak.

innate defenses

general defenses not targeting a specific pathogen

adaptive immunity

has the ability to target cells of the body that are infected with pathogens, while also responding to any pathogens that are free in the blood or interstitial fluid of the body.

As the viruses exchange genetic material

hey evolve into new forms that can then be transmitted to humans, causing flu outbreaks.

When some individuals with certain traits in a population have a _____ survival and reproductive rate than others, they _________ these better adapted genetic features to their offspring.

higher; pass on

viruses are an excellent example of

how evolution occurs over time

By recognizing the mechanisms through which organisms change over time, or evolve, we gain insight into which of the following?

how to design better medications such as antiviral agents and vaccines, resistance to insecticides and antibiotics, how the organization of life on our planet reflects evolutionary history

macrophages, dendritic cells and neutrophils are

in our immune system to destroy pathogens by phagocytosis and it is nonspecific to what pathogens it destroys

human influenza viruses originate

in pigs or birds

All vaccines contain

inactivated viruses

The change in the heritable traits of a population continues because natural selection __________ the frequency of the advantageous trait in the population and ___________ the frequency of detrimental traits.

increases; decreases

two different forms of the influenza virus are

issued during the year

The most common flu vaccine is called a trivalent vaccine because

it contains three different strains of inactivated viruses.

Epithelial cells

line and cover organs.

lymph nodes

tissue where interstitial fluid is filtered and cleansed by white blood cells called macrophages

red bone marrow

tissue where the lymphocyte cells of the body are produced. location where B lymphocytes mature

Natural selection favors variation, which increases the ability of the individual to reproduce and pass the

trait on to the next generation, and acts against detrimental traits.

Steps of an inflammatory response

1. damaged tissue and nearby immune cells release histamine 2. The macrophages identify and destroy any bacteria or viruses in the wound area 3. Neutrophils remove dead cells and any pathogens in the area by phagocytosis 4. clotting factors close off the wound. this causes pressure to build and accounts for the red, tender appearance of inflammation

Historically, viruses have not been classified as living organisms. Which of the following characteristics of life excludes viruses from being classified as living organisms?

Ability to process energy and materials

occurs when a mutation causes a change in the H and N spikes on the influenza virus.

Antigenic drift

Disruptive selection

Changes in the environment cause the average, or most common, form of variation to be detrimental and favors the variants at the ends of the distribution

evolution explains almost every aspect of biology including

Ecology Genetics Anatomy and Physiology Microbiology Systematics

Thomas Malthus

Economist who stated that populations (in this case, humans) sometimes increase at rates faster than their food supply can increase, thus creating competition.

Charles Lyell

Geologist who proposed that the Earth's surface is dynamic and constantly undergoing erosion and uplift, which explained how the different fossil layers were formed.

cell mediated immunity makes use of

Helper T cells (white blood cells produced in the bone marrow)

________ in a gene can produce a new or altered ________ that may encode for a unique trait. The new trait could be advantageous or disadvantageous to members within a population but is only able to persist if the new allele is _______

Mutations; allele; heritable

Erasmus Darwin

Naturalist and philosopher who proposed that evidence from animal development and animal breeding suggested that species may evolve over time.

Those individuals most at risk of developing serious symptoms are:

Over the age of 65 Have preexisting medical conditions (high blood pressure, diabetes, etc) Obese Immune compromised

Stabilizing selection

Selection favors the most common form of variant for the trait, and selects against the extreme variants.

Biologists have identified three different ways that natural selection can influence the variation for a trait in a population.

Stabilizing selection Directional selection Disruptive selection

The virus will begin using the epithelial cell's machinery to make more viruses. This will lead to:

The accumulation of fluid in the lungs Dead of epithelial cells Activation of the immune system

what is natural selection?

The idea that the fittest survive and pass along their traits to their offspring.

inactivated viruses

a weakened virus or viral genetic material along with preservatives.

In some instances, an intermediate host, like a pig, allows for the exchange of genetic material between two different strains of the influenza virus

an avian influenza strain and a human virus strain.

the N spikes

assist with entry into the host cells

The SARS-CoV 2 virus enters host cells by

attaching to ACE2 receptors.

he immune system monitors our

body fluids for the presence of pathogens

the chemical signals of the immune response are collectively called

cytokines

The immune system will activate near by white blood cells, which will release chemicals called

cytokines.

Darwin described the process of evolution as _________ a progression in which species change and eventually give rise to new___________ over time. All living things, therefore, can trace their descent to an_________

decent with modification; species; ancient common ancestor

Line of evidence 2, _____, is the comparison of genetic and biochemical similarities to indicate evolutionary relationships.

genetic material

Mutations are constantly occurring in the

genetic material

The differences between heritable traits of organisms of a population, also known as ________ is the primary force driving the mechanism of__________

genetic variation ; natural selection

COVID mostly attacks the respiratory system but

long-term impacts on other body systems have been seen.

If not blocked by the immune system, the virus migrate to the

lower respiratory tract where they infect the alveoli cells

The cycle of viral infection that will rapidly result in the death of a bacterial cell is called the ______ cycle.

lytic

There are two basic methods by which the influenza virus changes its genetic information:

mutations or reassortment

Jean-Baptiste Lamarck

naturalist who believed that complex life forms are descended from simpler forms. Proposed that individuals can acquire characteristics that enable them to evolve over time. This idea is referred to as inheritance of acquired characteristics.

In the influenza strain name A/Singapore/INFIMH-16-0019/2016 A(H3N2)-like virus, this was the ______ strain isolated in 2016 in this region.

nineteenth

The avian influenza virus may typically infect and transmit the virus among

one animal species at a time

evolution is recognized as

one of the unifying theories of biology

spleen

organ where blood is filtered and cleaned by the action of white blood cells in the macrophages

Most of the flu-like symptoms that we attribute to the virus or actually caused by

our own immune system

Mutations represent the source of genetic variation in a

population

Cytokines alert other cells and body systems to the

presence of a pathogen

B lymphocytes

produce antibodies to target specific antigens in the fluids of the body and they are specific about what pathogens they destroy (produce antibodies)

neutral mutations

produce neither adverse or helpful changes and they do not change the protein

he immune system is responsible for

protecting our bodies from foreign pathogens

A change in the nucleotide sequence of a DNA molecule can change the sequence of amino acids in a

protein thus changing the properties of that protein

Amino acids are the building blocks of

proteins

The initial infection can happen anywhere along the

respiratory tract

the lymphatic system s responsible for

returning body fluid to the circulatory system (blood)

which of the following is an antigen on the corona virus that is detected by the immune system?

s spikes

The accumulation of evidence supports that _____ change over time and that this change is the result of evolution by________

species; natural selection

Natural selection leads to an evolutionary change due to differential ____________ rates of individuals, because of differences in traits.

survival and reproduction

cell mediated immunity

target cells of our bodies that are presenting antigens

T lymphocites

target cells that have been infected by a specific pathogen and they are specific about what pathogens they destroy

adaptive immunity

targets specific antigens associated with a pathogen

The primary targets of the influenza virus are

the epithelial cells lining the respiratory system.

Line of evidence 3, ______, is a line of evidence that provides information on transitional species.

the fossil records

The H spikes of Influenza A identify

the host cells

They quickly enter into the respiratory system and travel down

the pharynx into the trachea and lungs.

SARS-CoV-2 also enters the body through

the respiratory system

From the perspective of a biologist, evolution is one of the unifying_______ or a widely accepted explanation for how the natural world works.

theories

evolution explains the

theories and diversity of life, as well as why organisms are well adapted to their environments

Central Dogma

theory that states that, in cells, information only flows from DNA to RNA to proteins

beneficial mutations

they can change in a way that increases the fitness of an organism

there are several types of genetic mutations

they include neutral, beneficial, and harmful

The most common vaccine contains three inactivated viruses. This is called a

trivalent vaccine

By recognizing the methods by which organisms change over time, or evolve,

we gain insight into how to design better medications, such as antiviral agents and vaccines.

Often, viruses are picked up on the hands and introduced to the body when

we touch our faces or mouth or handle food