Flashcards
Communicable diseases
Cards in this deck (19)
- 1Define the term parasite.lives , in / on , host ;
gains nutrition / feeds , from (host) ;
at the expense of / harms (host) ; - 2In patients with IDA, anaemia is caused by the destruction of erythrocytes (red blood cells) by phagocytosis. Suggest why erythrocytes that contain Plasmodium are more likely to be destroyed by phagocytosis than healthy erythrocytes.(different) chemicals that attract phagocytes (released from
infected erythrocytes) ; - 3Describe how the structure of antibodies allows them to perform their function.2 light chains and 2 heavy chains / 4 polypeptide
chains ;
variable region allows , binding / attachment , to
antigen ;
two variable regions allow binding of more than
one (of the same) antigen ;
variable region on different antibodies allows specificity
to different antigens ;
constant region allows , recognition by / attachment to /
binding to , (named) phagocytes ;
hinge (region) allows flexibility ;
disulfide , bonds / bridges , hold , polypeptides / light
and heavy chains , together ; - 4Outline the mode of action of antibodies in defending the body against pathogens by describing the processes of neutralisationcover / block , binding site / antigen / receptor site (on
pathogen) ;
bind to toxins ;
prevent , binding / entry , to (host) cell ; - 5The term immunity is often used when describing how vaccines work. In a piece of school homework a student wrote: “Bacteria can evolve quickly and many are now immune to antibiotics.” Explain why the student’s use of the word ‘immune’ was incorrect.immunity involves / bacteria do not have , lymphocytes /
white blood cells / antibodies / memory cells /
plasma cells / an immune system ;
(correct term is) resistant ;
bacteria are unicellular / only multicellular organisms
(can) have an immune response; - 6Explain how phagocytes are able to pass from the blood into the tissue fluid.obed / narrow , nucleus ;
(cells) can change shape ;
can squeeze / move / fit / AW , between cells
/ through pores , in (walls of) capillaries ;
histamine makes , capillary walls /
endothelium , leaky ; - 7State two features of the malarial parasite that indicate that it is not a prokaryotenucleus / nuclei ;
other named organelle /
membrane bound organelles ;
linear chromosomes ;
DNA, associated with / AW, histones / protein ;
80S / 22nm / large, ribosomes ;
large cells / AW ;
no cell wall ; - 8The malarial parasite is carried by an insect, the female Anopheles mosquito. (i) Describe how the mosquito transmits the malarial parasite to a human.(mosquito), is vector ;
Plasmodium / parasite, present in (mosquito), saliva /
salivary gland ;
idea that infected mosquito, feeds on / bites, human ;
Plasmodium / parasite, passes (from saliva) to blood ; - 9In order to fight the spread of malaria, insecticides have been used in areas where the Anopheles mosquito breeds. One problem that can occur when using insecticides in this way is the development of insecticide resistance. Suggest one other reason why some people might be concerned about using insecticides.destruction of a species is, morally / ethically, wrong ;
might cause unintended health problems in humans ;
might harm, other / unintended, species ;
idea of bioaccumulation / biomagnification ; - 10—
- 11Suggest why the influenza vaccine has to be changed each yeardifferent strains of the virus / virus mutates (each year) ;
(new strains have) different antigens ;
idea that antibody produced , needs to match new strain /
antigen ; - 12Identify the infective agent that causes AIDS.human immunodeficiency virus / HIV ;
- 13The infective agent that causes AIDS takes control of the T lymphocytes of the host. Using the information in Fig. 1.1, suggest why the infective agent is able to ‘take control’ once it has entered the T lymphocytes.reverse transcriptase in (host) nucleus ;
viral DNA, (inserted) in (host), chromosome / DNA ;
idea of: (viral) RNA / mRNA produced / transcribed ;
(to) code for / make / translate, viral proteins ; - 14Describe how cytokine molecules can stimulate specific groups of B lymphocytes to divide.cytokine / interleukin / receptor has, specific / unique,
shape ;
(cytokine / interleukin), binds / attaches / bonds to / fits into,
receptor ;
receptor on (cell surface) membrane (of B lymphocyte) ;
(receptor and cytokine have) complementary shapes ;
activates / stimulates, clonal expansion / mitosis ; - 15Explain how bacteria cause food spoilage.bacteria / (bacterial) cells, divide / increase in number / multiply /
reproduce / proliferate / replicate ;
(secrete) enzymes / named enzyme ;
food, digested / broken down ;
protein / named protein / polypeptides → peptides / amino acids
OR
fat / triglycerides → fatty acids
OR
starch / amylose / glycogen → glucose / sugar ;
production / release / excretion / secretion, of,
toxins / named toxin / waste products ;
(causes) change in, appearance / smell / texture / taste ; - 16Food can be preserved by keeping it at low temperature in a refrigerator or freezer. Name two other methods of food preservation and state how each method works.salting ;
lack of water due to, osmosis / low water potential (outside cell) ;
sugar ;
lack of water due to, osmosis / low water potential (outside cell) ;
(air / freeze) drying ;
idea that enzymes cannot mobilise /
intracellular transport impaired /
reactions have no medium in which to occur /
(microbes) cannot move ;
pickling / (use of) vinegar ;
(low pH) denatures / changes tertiary structure of /
changes 3D shape of, enzymes / proteins
OR
substrate no longer fits active site / active site shape changes /
prevents ESC ;
heat treatment / cooking ;
denatures / changes tertiary structure of /
changes 3D shape of, enzymes / proteins
OR
substrate no longer fits active site / active site shape changes /
prevents ESC ;
irradiation / UV / gamma rays / X-rays / ionising radiation ;
destroys / damages / changes / mutates,
DNA / genes / genetic material ;
smoking ;
(so exposed to) antibacterial / named antibacterial, chemical(s) ;
vacuum packing / canning / bottling ;
microorganisms cannot respire aerobically ; - 17Describe the actions of the B lymphocytes in the immune responsehumoral response ;
(B) cell / lymphocy ,
has antigen receptor / carries antibody on its surface ;
specific to / matches / complementary to , only one antigen ;
clonal selection ;
selection / activation , of , appropriate / specific ,
B lymphocyte / cellB ;
by , macrophages / antigen presenting cells / dendritic cells /
T helper cells / cytokines / interleukins ;
clonal expansion ;
(selected cell) divides by mitosis / clones ;
(B) cel , differentiate / specialise ;
(B cells) form , plasma / effector , cells ;
(which) secrete / produce , antibodies ;
antibodies are , specific / complementary , to antigen ;
(B cells) form memory cells ;
Either (memory cells) long-lived / remain in circulation /
remain in body / provide immunological memory
or
(provides) secondary response
or
faster / stronger , response to subsequent exposure
(of same antigen / pathogen / parasite) ; - 18When antibiotic growth promoters were used, it was claimed that the meat was of better quality, with less fat and increased protein content. Suggest two further benefits of using antibiotics.reduces / prevents (infectious) disease ;
prevent, problems / named problem, with gut ;
digest food more, efficiently / easily / quickly ;
greater proportion of, food / energy,
can contribute to growth ;
reduce risk of transmitting, pathogens / named pathogen, to
humans ; - 19—
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- A level Biology Flashcards on Communicable diseases, created by Harsimranjot Kaur on 07/04/2021.
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- Harsimranjot Kaur
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