from pp Flashcards
how do the characteristics of inflammation help in response
- pain alerts the person that there is an injury
- warmth speeds up {chemical reactions / skin cell division
/ phagocytosis / increases rate of enzyme activity (of
person) / defence mechanisms} - swelling results in more {blood / white blood cells /
platelets / phagocytes / antibodies/ tissue fluid} (to the
wound) - redness results in more {blood / white blood cells /
platelets / phagocytes / antibodies} (to the wound)
what is the difference between bactericidal and bacteriostatic antibiotics
bacteriostatic inhibit the growth of bacteria in other words keeps the number of bacteria constant
bactericidal antibiotics destroy the bacteria in other words decrease the number of bacteria
how does gut flora (bacteria in the intestines)
- to compete with pathogenic bacteria for nutrients/space which would limit the growth of pathogenic bacteria
define habitat
- a place organisms live
define population
- organisms of one species living in a particular area
define community
a group of organisms of different species interacting in a particular area
calculation in investigation
- calculate the mean AND SD
define anthropogenic
- caused by effects of humans
- changes to mean temp.
how to calculate the age of a tree by the rings
- each year a ring will form
- the thickness of the rings will be different each year depends on the condition
define aseptic technique
- methods used to prevent contamination of culture
why using aseptic technique is important
- prevent the entry of bacteria that may compete with E.coli
- to prevent infection of the person with bacteria in culture that may be pathogenic
define biodiversity
- number of different species
- genetic diversity within a specie
state the meaning of the term biomass
how much organic matter present in organisms
why describe diagrams as model
because it is making predictions (1)
based on {knowledge / data} (1)
it is a visual representation (of what might happen) (1)
why are enzymes needed
- needed for metabolism
why two primers are needed in PCR
primers needed so that (DNA / taq) polymerase can bind (to
one strand)
because one primer is needed for each strand
because the DNA strands {are antiparallel / are
complementary / have different base sequences at each end}
how does TB result in death
- because formation of tubercles
- therefore insufficient oxygen for aerobic respiration
- organ failure
- weakens immune system so death from infection
how optical methods can be used to compare the growth rates of two populations
- both types of bacteria cultured in the same culture conditions
- use aseptic technique
- use light meter / light sensor
/ spectrophotometer /
colorimeter / cross
underneath the flask / shine a
light through and measure
{transmission / absorbance} - calibration curve used to determine concentration of bacteria
what are interferons
- interferons are secreted by infected cells (1)
they are anti-viral proteins (1)
preventing {viral replication / synthesis of viral proteins /
spread of virus} (1)
involved in activation of {macrophages / T killer cells}
what happens to the bacteria at the lag phase
- (no increase in number of bacteria) because the cells had to
{adjust to new environment / warm up / synthesise new
enzymes}
log
(increase in number of bacteria) as {conditions are suitable /
nutrients available / pH appropriate / oxygen levels
appropriate / appropriate temperature}
describe the method used in dilution plating
- use serial dilution
- sample added to agar and spread
state the characteristics of pioneer species
need to withstand {harsh / extreme} environments (1)
* need to be able to withstand {dessication / lack of shade} (1)
* have a low requirement for {minerals / mineral ions / named
mineral ion / soil}
* have {fast life-cycles / grow fast / reproduce asexually / produce lots
of seeds / wide dispersal mechanisms}
why succession occurs in stages
changes to the habitat have to take place before a different
organism can survive there
* credit named improvement g. make soil, improve soil,
provide food (for animals)
* credit organism that would appear in next stage following this
improvement e.g. (deeper soil) bushes / trees,
(food / shelter) animals
nuclear DNA is linear and mtDNA is circular (1)
* nuclear DNA has unbound {phosphate group / sugar} whereas
mtDNA does not (1)
* mtDNA has (far)fewer {phosphodiester bonds / base pairs}
