BSC1005 SSC Exam 1 Review
Life cycles of RNA virus
1- endocytosis (entering membrane) 2- fusion/uncoating (attachment) 3- injection of RNA virus genetic material 4- RNA synthesis 5a- RNA polymerase into mRNA 5b- Replication of RNA virus genetic material 6a- Polymerase translate RNA to mRNA 7- Assemble virus genetic material 8- Release
Replication of flu in resp. tract
1- hijacks cellular machinery of host cell 2- produces proteins that interfere with normal functions of epithelial cells causing adverse effects 3- epithelial cells continue to lose function causing them to go into apoptosis
How influenza gets into resp. system
1- human picks up virus on hands 2 puts hands on mouth nose or food 3- flu enters respiratory system through the pharynx then the trachea finally the lungs
How does the coronaviruses replicate
1- translates a couple peptides to form the RNA polymerase 2- assemble in the Golgi apparatus 3- become part of the envelope 4- N spike protein assembles the nucleocapsid
When were coronaviruses first discovered
1950
How many people are infected worldwide with the influenza virus
3 to 5 million people
How many people died of the spanish flu
30 to 50 million
How many cells are in the human body?
30 trillion
Prior to COVID-19, what was the shortest development time for a vaccine given to humans?
4 years
How many people were infected with the spanish flu
500 million
How many deaths are recorded due to the influenza virus
500,000
what percent of the population in the United States may need to be vaccinated in order to achieve herd immunity?
85%
What percentage of a population would need to be immune to prevent the spread of a contagious disease?
95%
Ingredient of Flu Shot Thimersol
A preservative that may be present in some multi-dose vials of the vaccine
Capsid
A protein coat that surrounds the genetic material of host cell. may have proteins attached, tail fibers or spikes, assist in attaching to host
Characteristics of living things present in viruses
Ability to change over time or evolve contain genetic material
Signal of immune response- Interferon
Acts as a signal to nearby cells that a cell has been infected by a virus
Penetration
After attaching, genetic material enters the cell, occurs by injecting genetic material into host cell, or by having the host cell fully engulf the virus called endopoptosis
Which ingredient in the flu vaccine helps the immune system identify the flu virus
Aluminum salts
describes the physical characteristics of the influenza virus?
An RNA virus enclosed in a spherical capsid surrounded by an envelope with spikes
The immune system will target any cell anywhere in the body if it is
An antigen-presenting cell (APC)
A macrophage with an attached pathogen to the surface is called
Antigen-presenting cell (APC)
Antigen
Any substance that prompts an immune system response (viruses or bacteria)
Spikes
Assist a virus in identifying and entering a host cell
Antiviral medications target which aspects of the viral life cycle
Attachment Uncoating Release
Characteristics of living things not present in viruses
Capable of processing energy or materials maintain an internal environment respond to external stimuli contain cell machinery to replicate DNA or RNA
Directional selection
Changes in environment direct natural selection, favors either end of extreme traits (extreme traits on either side) 1 extreme
characteristics that are considered to be evidence of natural selection that Darwin observed aboard the Beagle.
Collecting fossilized remains of extinct animals along the west coast of South America challenged Darwin's idea that the Earth was young. In regard to biogeography, Darwin discovered similar environments and animals with similar appearances in South America and Europe. Darwin noted that unique island finch species are descendants from the mainland species that have developed adaptations to survive on the island's food source.
Homologous structures represent which form of evidence supporting the theory of evolution?
Comparative anatomy Embryonic development
Flow of information except RNA viruses
DNA -> RNA -> Protein
events during inflammatory response
Damaged tissue and nearby immune cells release histamine causing fluid to leak causing more blood flow to wound Macrophages identify and destroy any bacteria or viruses in the wound Neutrophils remove dead cells and any pathogen in the area Clotting factors close the wound
Indirect effects of influenza virus on body systems
Digestive system; loss of appetite muscular system; joint and muscle aches nervous system; headache and fever integumentary system; chills
Thomas Maithus
Economist who stated that populations sometimes increase at rates faster than their food supply can increase, creating competition
E protein
Envelope proteins involved in assembly of virus and the exit of the virus from the host cell
RNA polymerase
Enzyme that flu uses to process genetic material for protein production?
Influenza targets which type of cells?
Epithelial cells
How do emerging viruses arise?
Evolutionary change changes in environment
Natural selection causes mutations.
False
One of the biggest setbacks to influenza research is the lack of ability of viruses to evolve over time.
False
Since viruses never change, an adaptive immune system is not necessary.
False
The closer the genetic information is between two species, the more distant their evolutionary relationship.
False
The closer two organisms are related, the more time there is for mutations to change their genetic information for a trait.
False
The genetic material is not a history of the organism's evolutionary past.
False
Northern hemisphere decides which strains of flu for vaccine in
February
Tikaalik and Archaeopteryx are associated with which type of evidence of evolution?
Fossil
Organ or Tissue Red bone Marrow
Function- tissue where the lymphocyte cells of the body are produced. Location where B lymphocytes mature
structural components of a virus.
Genetic material Protein capsid
All of the genes in an organism
Genome
Charles Lyell
Geologist who proposed that the Earth's surface is dynamic and constantly undergoing erosion and uplift
Signal of immune response- Interleukin
Glycoprotein that is involved in regulating the general immune response
How many total genetic changes have been documented in the coronavirus B.1.1.7 strain that is now circulating?
Greater than 20 genetic changes
Recombinant Vaccine process
H spike protein is added to a virus that insect cells infected insect cells are cultured to produce large amounts of the H spike protein virus is not used, the H spike protein is used to create vaccine
Influenza A has which spikes
H spikes and N spikes
Influenza in the Resp. tract
H spikes identify host epithelial cells by detecting specific glycoproteins on surface of host cell. N spikes then break down the membrane and enters the host cell Infection occurs at anytime from the nasal cavity to the lungs
RNA viruses
HIV, influenza, SARS-CoV-2
Viruses Name
Host, type of strain, year of isolation
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
Physical Barrier for Pathogen- Stomach
Hydrochloric acid destroys bacteria and other pathogens
Symptoms associated with the flu are largely the result of a reaction by which body system
Immune System
characteristics that explain the process of natural selection.
In a population, individuals vary in their heritable traits In a population, individuals struggle to exist In a population, individuals differ in their fitness. Over multiple generations, populations become adapted to their environment.
Natural Selection
Individuals vary in their traits- variations in heritable traits Individuals struggle to exist- competition between population Individuals differ in their fitness- favorable traits for reproduction Populations become adapted to the environment
When does histamine cause capillary beds to be leaky, thus slowing the movement of pathogens into a wound?
Inflammatory response
what is on the surface of every body cell with a nucleus to identify self?
MHC-I
Physical Barrier for Pathogen- Respiratory tract
Mucous trap microbes; they contain chemicals that protect against pathogens(cilia)
Process produces changes in the genetic material
Mutations
Erasmus Darwin
Naturalist and philosopher who proposed that evidence from animal development and animal breeding suggested that species may evolve over time
Jean Baptiste Lamarck
Naturalist who believed that complex life forms are descended from simpler forms
How does the immune system remember past pathogens?
Not all B cells are used in response to a pathogen, the reserves are used when the body is exposed to the same pathogen allowing faster and efficient responses; Memory T cells
Most accurate test to detect covid-19
PCR molecular test
not be a good source to consult for additional information on the new COVID-19 vaccines?
Personal websites and blogs
What produces antibodies?
Plasma cells
B lymphocytes
Produce antibodies to target specific antigens in the fluids of the body (specific)
how an influenza virus identifies and infects its target cell?
Proteins located on the capsid of the virus allow the virus to attach to molecules on the surface of a host cell. The capsid proteins of a virus may attach to protein receptors on the surface of the host cell. Upon identification of a specific protein molecule on the surface of the host cell, the virus can integrate into the host cell.
Which phase of covid-19 produces the symptoms
Pulmonary phase
Influenza evolution is studied by using its ___ to prove mutation records
RNA
Method of producing a vaccine not requiring use of the entire influenza virus
Recombinant method
Which of the following produces immune system cells?
Red Bone Marrow
Tamiflu specifically targets which part of the influenza virus life cycle?
Release phase of life cycle
medications to fight covid-19
Remdesvir, Paxlovid, and Lageviro steroid dexamethasone
Which protein in a coronavirus allows it to identify specific host cells for infection?
S proteins
Southern Hemisphere decides which strains of flu for vaccine in
September
Genes
Sets of DNA
Did antigenic shift or drift cause the most severe flu outbreaks in history
Shift
DNA viruses
Smallpox, chickenpox, herpes
common symptoms associated with the influenza virus?
Sore throat Congestion Body aches Fever
Attachment
Stage 1 of lytic cycle, recognizes and targets host cell for infection due to chape of the protein in the capsid of virus
T lymphocytes
Target cells that have been infected by a specific pathogen (specific)
What are the steps that must take place in a DNA virus to produce proteins?
The DNA is converted to mRNA and then to protein.
What important information about a virus is needed before an mRNA vaccine can be produced?
The genetic sequence of the DNA or RNA
true concerning the flu vaccine.
The influenza vaccine is designed to protect humans against three or four influenza viruses that are most likely to spread and cause a pandemic during the flu season. Flu vaccines take up to six months to prepare and are synthesized based on surveillance information sent to the five influenza centers across the world.
Organ or Tissue Spleeen
The organ where blood is filtered and cleaned by the action of white blood macrophages
genetic mutations have been slow to develop in the coronavirus causing COVID-19. How is this possible?
The virus contains proteins that are able to proofread and fix mutations.
How do the Pfizer and Moderna vaccines mentioned in this article differ from other traditionally produced vaccines?
These vaccines contain mRNA from the coronavirus causing COVID-19.
A comparison of genetic and biochemical similarities can indicate evolutionary relationships.
True
Influenza research involves constructing new vaccines and treatments.
True
Mutations are constantly occurring in the genetic material.
True
Mutations represent the source of genetic variation in a population.
True
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.
True
Newer vaccines are being designed to use other proteins within the capsid, called core proteins, as the basis for programming the adaptive responses.
True
Scientists are researching ways to use antiviral agents to combat parts of the viral life cycle and the development of a universal flu vaccine.
True
When comparing species, some traits are more common in closely related species than distantly related ones.
True
how flu vaccines are produced.
Vaccines contain either inactivated or weakened viruses. Vaccines include additives to preserve the vaccine's contents before use. People with egg allergies should pay attention to how the flu vaccine is made, since some flu shots may contain remnants of eggs due to the egg-based technology used to make the flu vaccine.
circumstances are necessary for evolution to occur?
Variation for a particular trait exists within a population. A particular trait must be able to be passed on to the next.
how do viruses reproduce?
Viruses are typically a piece of genetic material encased in a protein capsule. They are only capable of reproducing once inside a living host cell.
Georges Cuvier
Zoologists studying the fossil record and noticed that it showed a succession of different forms of life
pandemic disease
a disease that has spread globally; movement of a disease between geographically distant populations
Zoonotic Viruses
a disease that is transmitted from an animal host to humans; develops new characteristics as it is passed from host to host; antigenic shift
Glycoprotein
a protein with a sugar attached
How does the immune system distinguish self from nonself cells
a series of markers are on the plasma membrane of each cell
Antigenic shift involves
a single host cell being infected by viruses from two different animals formation of new combinations of H and N spikes on the virus slower adaptations by the immune system
Complement Proteins
act as a molecular tag identifying pathogens for destruction for the immune system; creates holes in bacteria's membrane
cytokines
act as an alarm to organ systems, alerts that a pathogen is present
cell-mediated immunity
adaptive immunity
When pathogens are ingested by the macrophages and dendritic cells of the immune system, they are digested and a small portion of the pathogen, __________, is attached to the surface of the macrophage.
an antigen
N spike
an enzyme called neuraminidase, breaks down the mucous material surround host cell, initiate penetration of the virus
Direct effects of influenza virus on body systems
apoptosis of epithelial cells accumulation of fluid in lungs activation of immune system due to inflammation in the lungs
Maturation
assembles the virus
cytotoxic T cells
attach to target cell and release a protein called perforin; then opens a hole in the membrane
Hyperinflammation phase
body develops acute respiratory syndrome requiring additional oxygen and potentially ventilation
amino acids
building blocks of proteins, DNA contains the specific sequence of aa for the protein
What can antibodies do?
can clump together around am antigen effectively inabling it; can bind to the antigen and flag it for destruction from a natural killer cell
Example of Coronavirus SARS-CoV-2
causes covid-19
Example of Coronavirus MERS-CoV
causes middle eastern respiratory syndrome
Example of Coronavirus Sars-CoV
causes sever acute respiratory syndrome
Release
causes the host cell to burst(lysis) or exits through membrane (exocytosis). Viruses with outer envelope leave by exocytosis
Mutation
change in the sequence of nucleotides in the genetic material
Evolution
changes in species or population over time
Disruptive selection
changes in the environment cause the common traits to be detrimental, favors variants at both ends of distribution (2 extremes)
Cytokine restricts blood vessels in the skin to conserve heat
chills, Integumentary system
Capsid Protein
complex shapes allowing the virus to target specific molecules on the surface of the target cell, the molecules can other proteins, receptors on the surface of cell, and molecules integrated in the membrane
Proteins
complex, 3dimensional shapes
Capsid DNA or RNA
components of a virus
Nucleotides
contains the information for a trait creating building blocks called (GC,AT)
RNA Virus alt
convert RNA to mRNA
What is a Coronavirus
crown like spikes emerging from the surface of the virus; respiratory and intestinal disease
Antigenic
describes organisms that can evade our immunce system defenses
natural killer cells (NK cells)
destroy cells of the body that have been infected by viruses or bacteria (nonspecific)
Macrophages, dendritic cells, neutrophils
destroy pathogens by phagocytosis (nonspecific)
Antigen covid-19 test
detects for previous exposure to the virus; does not detect current infection of virus
What happens after a B cell is activated
develops into a plasma cell, producing large amounts of antibodies for the specific detected antigen; divides rapidly producing more identical B cells allowing for more antibodies to be created
outbreak
disease spreading beyond original population
Core proteins
don't change at the same rate as H and N spike proteins similar between flu strains
Symptoms of covid-19
dry cough fever chills muscle pain loss of taste or smell
Ingredient of Flu Shot Aluminum salts
enhances the ability of the immune system to detect the virus
Granzymes
enter hole of target cell made by cytotoxic T cells and causes the target cell to undergo apoptosis
epithelium cells
epithelial cells arranged in thin layer of tissue (one cell layer thick)
The primary target of the influenza virus is the
epithelial cells lining the respiratory system.
When do mutations occur
exposure to radiation chemicals mistakes in copying genetic information for next gen cells viruses that undergo endocytosis can cause mutations
Viruses
find a host cell, hijack metabolic machinery of host cell, then makes copies of itself
Protein on a capsid
finds specific type of host cell for virus
nasal swab test
fluids from respiratory tract examined for presence of covid-19
epithelial cells
form boundary between the tissues of our bodies and internal environments
helper T cells
form of T lymphocyte; has the ability to recognize the combined MHCC-II antigen receptor on the macrophage; divides to produce cytokines alerting the antibody-mediated responses
endemic disease
found at normal levels in the population
Organ or Tissue Lymph Nodes
function- tissue where the interstitial fluid is filtered and cleansed by white blood cells called macrophages
Most important piece of evidence for evolution
genetic material
which protein can be found in the plasma membrane
glycoproteins
antigentic shift
greater consequences to humans 2 forms of the same virus infect the same cell most often occurs in pigs and birds host cell may manufacture viral particles from both viruses and then reassemble into a new mutation
Cytokine presence alerts the hypothalamus in the brain to increase body temp
headache, fever Nervous system
H spikes
hemagglutinin, type of glycoprotein that identified the receptors of a host cell
H Spikes main function
identifies a specific molecule on the surface of the cell
What do Macrophage and dendritic cells do
identify pathogens; destroy pathogens by phagocytosis
Cytokine storm caused by covid-19
immune system produces abnormally large number of protein molecules called cytokines
Pulmonary phase
immune system responds to the covid-19 virus in the airways and alveoli of the lungs; produces the symptoms of covid-19
Ingredient of Flu Shot Formaldehyde
inactivates any toxins from the viruses or bacteria that may been present during production
Problems with RNA viruses
increased chance of mistakes/mutations of genetic material due to more steps involved causing more variations leading to new strains of the RNA virus
Signals of immune response- Histamine
increases the permeability of the capillaries and causes fluid to be released into the area of a wound
Fertilized Chicken egg Vaccine process
incubate for a few days viruses replicate during incubation liquid portion of egg is extracted viruses are killed virus particles are isolated, purified finally produce vaccine with virus particles
Herd immunity is considered a reduction in
individuals susceptible to infection.
How does a flu vaccine work?
injects the antigens of a pathogen into the body signaling an immune response; causing memory B and T cells to be produced
Protective proteins
innate defense
Genetic Material of a virus contains-
instructions to manufacture the proteins that compose the capsid surrounding the virus
major histocompatibility complex proteins (MHC)
involved in identifying self cells
Lymphatic system
involved in returning fluids called lymph from the tissues of the body back to the circulatory system
Cytokine breaks down muscle fibers and accumulation of fluid
joint and muscle aches. Muscular syst.
Example of Coronavirus 229E, NL63
known to produce symptoms similar to the common cold
Antibodies
large protein molecule that binds to specific antigens
CRISPR technique
looks for genetic material of the virus
Cytokine reduces the action of appetite centers in the brain
loss of appetite, nausea, vomiting. Effects digestive system
What happens when a pathogen is ingested?
macrophage and dentritic cells ingest the pathogen then digested then a small portion of the pathogen attaches to the surface of the macrophage
Phospholipids
makes up the plasma membrane
M protein
membrane proteins involved in assembling the virus
PCR technique
molecular tests
One role for the immune system
monitor lymph fluid for the presence of pathogens done in the lymph nodes
H spike and N spike variations are caused by
mutations
Which of the following are correct regarding antigenic drift?
mutations may be introduced by the action of the RNA polymerase enzyme it may result in a reduced fidelity for flu vaccines it is due to minor mutations in the structure of the H and N spikes
Physical Barrier for Pathogen- Skin
normal bacteria on the surface, along with chemicals released by oil and sweat glands, inhibit bacterial growth
What surrounds the single stranded RNA in the coronavirus
nucleocapsid
Antigenic Drift
occurs when there are small changes in the surface spikes of the influenza virus causes flu vaccine to be less effective due to mutations after creation
Targets of the cell life cycle for antiviral medications- Uncoating
once inside the cell some viruses provide an enzyme to remove their genetic material from the capsid
Spleen
organ where blood is filtered and cleaned by the action of macrophages
Risks Factors of Covid-19
over 65 medical conditions such as asthma, kidney disease, diabetes, heart disorders obesity compromised immune systems
Evolution is described as the change in heritable traits of a(n) __________ over a period of time.
population
MHC I Markers
present on every nucleated cell of the body general self identification tag
MHC II Markers
present on the immune system cells that provide the link between the nonspecific and specific immune responses
Ingredient of Flu Shot Antibiotics
prevents bacterial growth during the preparation and storage of the vaccine
epithelial cells lining for respiratory system
primary target of the influenza virus
5 characteristics to determine if something is alive or not
process energy and materials maintain an internal environment respond to stimuli from the environment reproduce adapt to changing environmental conditions
B lymphocytes immune response
produces antibodies; second form of adaptive immunity; referred to as antibody-mediated immunity
Immune system is responsible for
protecting our bodies from foriegn pathogens, such as viruses and bacteria works closely with lymphatic system
cytochrome c proteins
protein used in many organism used to get energy from nutrients such as carbohydrates. proves the closer 2 organism's DNA to each other the closer in evolution they are.
Antigens are usually
proteins or large carbohydrates that are specific to pathogens
Transitional fossils
provide an indication of the timeline of changes in a species overtime
converting RNA to mRNA in influenza
provides a from of RNA polymerase capable of converting the viral RNA to mRNA. translates to form the viral proteins needed for biosynthesis
epidemic disease
rapid increase in infection rates among the population
ACE 2 (angiotensin converting enzyme 2)
receptors involved in regulating peptide hormones (angiotensin) which controls blood pressure
epithelial cells role
regulate the activities of the body, checks every substance entering or leaving before entering the blood stream
Angiotensin in the lungs
regulates amount of blood flowing into the alveoli; exchanges gas
Lysogenic Cycle Stages
remains inactive in host cells after penetration, host cell divides which replicated the host DNA and virus DNA are replicated. remains inactive until environmental factors signal for it to reenter the lytic cycle 1) Attachment 2)Penetration 3)Integration with Host DNA 4)Host cell divides 5)Biosynthesis 6)Maturation 7)Release
Ingredient of Flu Shot Egg Protein
remnants from the production of the vaccine
RNA Virus
requires host cell's DNA to start protein synthesis
Cell Based Vaccine process
same as chicken egg procedure except instead of egg cells it is mammalian cell cultures
Stabilizing population
selection favors common traits and selects against extreme variants (Average)
Hox genes
similarity in embryonic development is due to the action of a series of developmental genes called? (control) early embryonic development of all animals
Barrier to entry (innate defense)
skin and mucous membrane
T cells have the ability to activate
specific B cells
Researchers are most concerned about mutations that develop in the _________ protein(s) on the coronavirus that causes COVID-19.
spike
S protein
spike protein responsible for the attachment of the virus to specific receptors on the host cell
Ingredient of Flu Shot Gelatin(MSG)
stabilize the vaccine and protect it from temperature variations during storage
Homologous structurees
structures that are similar because they have been inherited from a common ancestor
analogous structures
structures that serve the same function, appear the same, but evolved independently as adaptations to the environment
Alfred Russel Wallace
studied biogeography of south pacific islands, proposed concept of speciation(how a population changes into a new species over time)
Nucleocapsid
surrounds the genetic material of the coronavirus; helical protein structure
Targets of the cell life cycle for antiviral medications- Attachment Phase
target either the molecules on the surface of the cell the proteins that the virus uses to attach to the cell (spike proteins)
Tamiflu
targets the release stage inhibits a viral enzyme called neuraminidase allows the virus to leave the host cell
plasma membrane
the barrier between the interior of the cell and the exterior environment
warmth and pain when sick is caused by
the immune system engages the pathogens in the lymph nodes
Thymus
the organ where T lymphocytes mature
Mutations causes
the protein to become non-functional which can result in the undergoing apoptosis can cause the final protein to have slightly different shape or configuration
T lymphocytes
travel to thymus matures to develop receptors recognizing a single form of antigen
H1N1 and H3N2
two forms of influenza A in humans
Newer vaccines are designed to
use other proteins within the capsid of the virus as the basis for programming the adaptive repsonses
Biosynthesis
virus hijacks machinery to make new capsid proteins and copies of the genetic material. consumes host cells energy and materials
asymptomatic phase
virus incubates; no symptoms of covid-19; still infectious
Targets of the cell life cycle for antiviral medications- Release
viruses provides an enzyme that interacts with specific molecules in the cell's membrane to allow the newly formed viruses to escape the host cell
Thymus
where T lymphocytes mature
lymph nodes
where interstitial fluid is filtered and cleansed by white blood cells called macrophages
Red Bone Marrow
where the lymphocyte cells of the body are produced. location for maturation of B lymphocytes
