bacteria/eukaryotes have no internal compartments?
bacteria/eukaryotes have cell size which is usually about 1um in diameter?
bact/euk. can exist in form of multicellular organisms?
bacteria/eukaryotes chromosomes are linear pieces of DNA associated w/proteins?
bacteria/eukaryotes reproduce by binary fission?
bacteria/eukaryotes flagella are composed of a single fiber of proteins that spins like a corkscrew?
bacteria/eukaryotes can perform various types of metabolic activities?
Escherichia coli are gram-negative/gram-positive eubacteria?
conjugation is a process carried out by bacteria and eukaryotes/eukaryotes only
bacteria and eukaryotes
Escherichia coli have pili and flagella/only flagella as appendages
pili and flagella
chemicals that interfere w/life processes of bacteria are called antibiotics/toxins
cyanobacteria: photosynthetic, chemoautotrophic or heterotrophic?
purple sulfur bacteria: photosynthetic, chemoautotrophic or heterotrophic?
bacteria that preform nitrification: photosynthetic, chemoautotrophic or heterotrophic?
Rhizobium: photosynthetic, chemoautotrophic or heterotrophic?
consumers or decomposers in food chains
Bacteria that obtains energy from inorganic substances.
Bacteria that make their own food using light energy.
what resources in your body do bacteria on or in body compete for?
protein, minerals, fats, carbs and vitamins
what is the name of the bacterium that causes Lyme disease?
what causes tooth cavities?
dense collections of bacteria in mouth (Steptococcus mutans)
what are two basic ways that bacteria cause disease?
by metabolizing host or by secreting chemical compounds (toxins) into environment
Alexander Fleming noticed that a certain fungus secretted a substance called ___ that was toxic to bacteria
Antibiotics cannot be used to cure diseases caused by ___
many fermented foods, such as cheese and buttermilk, are made with the assistance of bacteria (t/f)
chemoautotrophic bacteria can be used to increase mineral content of ores (t/f)
scientists have not yet learned how to modify bacteria genetically to yield characteristics that are useful to humans (t/f)
segments of nucleic acids contained in a protein coat are called
another name for protein coat
capsids may contain ___ or ____ but not both
RNA or DNA
many viruses have a(n) ___ which surrounds the capsid and helps the virus enter cells
an envelope consists of proteins, lipids and ___ derived from the host cell
viruses that infect bacteria
any agent that causes disease
the cycle of infection, replication and cell destruction is called the
the viral gene inserted into the host chromosome in the lysogenic cycle is a
the type of cycle where the cell isn't destroyed by a viral reproduction (the father cell, at least) is the
viruses that evolve in a geographically isolated area and are pathogenic to humans are
infectious disease agents that have a single strand of RNA and have no capsid are called
there is a newly discovered class of infectious particles called ____ which are composed of proteins w/no nucleic acid
an outgrowth on bacteria that attaches to surfaces or other cells
a gel-like layer outside cell wall and membrane
chemicals that interfere with life processes in bacteria
bacterial structures that can survive environmental stress
a process in which two organisms exchange genetic material
chemicals poisonous to eukaryotic cells
series of events that suppress infection and speed recovery
when the body's temp rises when fighting a pathogen (many bad bacteria don't grow well in heat--> slow rate of bad growth)
defense mechanism containing around 20 different proteins which circulate in blood and become active if encounter pathogen
protein released by infected cells (causes nearby cells to produce enzyme that prevents viruses from making proteins/RNA)
WBC that engulfs and destroys pathogens (and self, in process)
WBC that eats and kills pathogens in encounters
how does skin help defend body against infection?
acts as nearly impenetrable barrier to invading pathogens, keeping them outside the body (reinforced w/chemical weapons like oils and sweat)
how do mucous membranes help defend body against infection?
layers of epithelial tissue that produce mucus (viscous fluid) and serves as barrier like skin to pathogens and produce chemical defenses (mucous traps pathogens)
how does a natural killer cell defend the body against pathogens?
they attack cells infected w/pathogens by puncturing a hole into it's cell membrane water then rushes into the infected cell causing it to swell and then burst
cytotoxic T cells
attack and kill infected cells
label invaders for later destruction by making plasma cells which in turn release antibodies
helper T cells
activate both cytotoxic T cells and B cells
what are antigens?
substances that trigger and immune response
what is the relationship between antigens and WBC?
WBCs of immune system are covered w/receptor proteins that respond to infection by binding to specific antigens on surface of infecting microbes
what are the two main parts of an immune response?
the T cell response (muscles: active, cell-meditated, destroys pathogens) and B cell response (brain: passive, humoral, aids in removal of pathogens)
how do helper T cells first become part of the immune response to invasion by virus?
they are activated by macrophages
how does interleukin-1 amplify the body's response to an invasion
activates Helper T cells, which activated cytotoxic T cells and B cells, while also causing helper T cells to release interleukin-2 which stimulated further division of helper T cells and cytotoxic T cells
what is the role of B cells in immune response?
they divide when activated by interleukin-2 and develope into plasma cells
what is the role of plasma cells in the immune response?
cells that release special defensive proteins into the blood (antibodies) which, upon exposure to a specific antigen can bind to that antigen
how do antibodies help fight viral infections?
they bind to the viral antigen on the virus and on infected cells and mark the virus and infected calls for destruction
diseases transmitted from person to person are considered contagious or ___
after an immune response, some B cells and T cells become ____ cells, which protect against previously encountered pathogens
what step in Koch's postulates? the pathogen is taken from the second animal and is grown in a laboratory culture. the pathogen should be the same as the original pathogen
what step in Koch's postulates? when the pathogen is injected into a healthy animal, the animal developes the disease
what step in Koch's postulates? the pathogen is found in an animal w/the disease
what step in Koch's postulates? the pathogen is isolated from the sick animal and is grown in a laboratory culture
resistance to a particular disease
a medical procedure used to produce immunity
a way of deceiving the immune system when viruses produce new antigens (disguise) that the immune system doesn't recognize
solution that contains a dead or modified pathogen that can no longer cause disease
an autoimmune disease
a disease in which the body launches an immune response against its own cells, attacking body cells as if they were pathogens
someone whose blood contains antibodies to HIV is said to be ___ _____
the most common method of HIV transmission is through ____ ____
give two examples of allergy-causing antigens
pollen and the feces of dust mites
what is histamine and it's role in allergic reactions?
a chemical released when cells are exposed to alley-causing antigens causes swelling, redness, increase mucous production, runny nose, itchy eyes and nasal congestion (the common symptoms of allergic reactions)
what defense attacks invading organisms during third defense?
what is produced in the 3rd level of defense
a protein produced in response to and counteracting a specific antigen (the immune response the antigen produces)
where are antibodies produced in body
in the thymus gland (in children), lymph nodes and spleen
what happens in an antigen-antibody reaction?
an antigen causes the production of a specific antibody and that antibody will react only with that particular antigen
body does it itself
get injection or something (don't have to fight off by self)
boy has mumps (passive or active)
an infant receives antibodies against measles in its mother's milk (passive or active)
a woman who has been exposed to hepatitis is given a shot of gamma globulin (passive or active)
fraction of blood that contains antibodies
what causes the rejection of many skin grafts and organ transplants
how can rejection of transplants be controlled
by drugs or radiation
under what circumstances have transplants been most successful?
between identical twins (body proteins are so similar, harder to be rejected)
first line of defense
non specific keeps out all invaders
second line of defense
non specific stop growth of any invader that gets part 1st line of defense
third line of defense
specific WBCs organize to destroy a specific type of invader ***creates memory of invaders so can defeat in future
purpose of 1st line of defense
block entry of pathogens (non specific)
exs of 1st line of defense
skin mucous membranes tears stomach acid other microorganisms
unbroken skin is pathogen proof dead surface layers scale off and remove pathogens acids in swear and oils inhabit growth of pathogens
lining of organ systems (digestive tract, respiratory tract, ect.) mucous is slimy to trap pathogens and acidic to inhabit pathogen growth cilia: hair like projections that filter particles and germs coughing and sneezing
secreted continuously by tear glands clean and lubricate eyes contain lysozymes (enzymes that destroy bacteria)
kills potential invaders in food
good bacteria that living in body crowd out and prevent bad bacteria from reproducing
purpose of second line of defense
when first line of defense falls, the second line of defense fights local infection (non specific)
exs of second line of defense
fever inflammatory response (inflammation)
increased temp is helpful (inhabits growth of pathogens and speeds up immune system reactions) high fever (over 103) is cause for concern (dangerous or even deadly b/c high temp destroys proteins and enzymes controlling important chemical reactions)
inflammatory response (of second line of defense)
injured cells and invaders release of histamines histamine causes inflammation- blood vessels widen, increased blood flow to area (redness, swelling, local fever, leaky capillaries enable macrophages and neutrophils to engulf pathogens)
dead cells and fluid left over from the inflammatory response
third line of defense purpose
to attack specific invaders (specific defense)
third line of defense exs
B and T cells organize specifically to attack H1N1 virus
three kinds of WBCs in 2nd line of defense and function
neutrophils: engulfs and destroys pathogens and sacrifices itself while doing so macrophages: ingest and kill pathogens natural killer cells: attack cells infected with pathogens by puncturing its cell membrane (causing water to rush in and pop the pathogen)
four types of WBCs in 3rd line of defense (Immune Response)
Macrophages: ingest and kill Cytotoxic T cells: attack and kill infected cells B cells: label invaders for later destruction by macrophages Helper T cells: activate both cytotoxic T cells and C cells