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Low Achieved
Candidate explains bacterial digestion
Incorrect description of fungal
digestion
Candidate explains bacterial
reproduction
Candidate describes fungal
reproduction as involving
the use of spores
The candidate has restated what they
wrote on page 2 with the additional
information that both can reproduce
asexually. Only 3 points = A3
This candidate has described three "Achieved" points; penicillin
was most effective, it has the largest no bacterial growth area,
and the agar plate should be sterile to prevent contamination
such as fungi.
Need more than "affect the experiment" or "to keep the
experiment honest" as an explanation for sterilising the
agar plate.
There is no description or explanation on how
the agar plate was inoculation
Saprophytes are micro-organisms that
feed on dead material - not live on / off
This candidate has offered no explanation of the temperature
changes, nor linked these changes to the life process
(respiration) of the micro-organism.
No evidence for Achieved or Merit points in this section (b)
The candidate has stated two Achieved points:
* the bacteria excretes CO2 (a very weak answer, barely
acceptable as an Achieved point)
* the bacteria is aerobic meaning they use oxygen
These additional statements for Question
1 are largely irrelevant (not asked for in
the question). They provide no additional
evidence towards a higher grade.
High Achieved
Candidate has explained bacterial digestion,
although they have used "excrete" instead of
secrete
Stated "extra-cellular digestion"
DNA is replicated, not split.
Binary fission stated
Candidate explains fungal reproduction as
involving spores which are dispersed.
4 points covered (2 at Merit level) = A4
The candidate has explained how an inoculation loop is used to
evenly inoculate the agar plate, i.e. by moving it in an 'S' shape,
turning the plate 90 degrees and another 'S' shape drawn = M point
Incorrect description / definition
This candidate has described how the temperature
increased and then decreased (from graph) but has not
linked this to the process of respiration
The candidate has given a descriptive answer with no
explanations. There are three descriptions (1 in part (b) and
2 in part (c) ) and therefore the grade for Question 3 in A3.