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Question 4
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(a) Identify specimens P, Q and R. [2 marks]
(b) Name the part of the host where each of specimens P, Q and Rean be found. [2 marks]
(c) Mention three ways by which specimen P is adapted to survive in the host. [3marks] .
(d) State three effects of specimen Q on the host. [3 marks]
(e) . List four diseases transmitted by specimen R. [2 marks]
. (f) State four control measures of specimen R. [4 marks] |
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This question was popular with the candidates. In 4(a) and (b), majority of the candidates could identify
specimens P (Tapeworm), Q (Liver fluke) and R (Tick) and name the part of the host where specimens P
(Intestine of host), Q (Inside the liver/bile duct) and R (skinlhody of host) can be found.
However, in 4(c), many of the candidates could mention ways by which specimen P (Tapeworm) is
adapted to survive in the host. In 4( d), most of the candidates could state the effects of specimen Q (Liver
fluke) on the host. In addition to this, in 4(e) and (f), majority of the candidates were able to list diseases
transmitted by specimen R (Tick) and state control measures of specimen R (Tick). |
The expected answers include:
Ways by which specimen P is adapted to survive in the host:
Head/scolex has suckers and hooks for firm attachment to host.
Head/scolex for sucking the nutrients and blood from host.
Has many segments/proglottids which have complete reproductive structures. These increase
their survival.
They have both male and female reproductive structures, which favours self fertilization.
They secrete chemicals which ensure their freedom from digestive enzymes of host.
Nutrients are absorbed by all surfaces of the body/large surface area.
Formation of cysts around the bladderworm, ensuring the survival of the bladderworm in the
reproductive cycle.
The proglottids contain several eggs which increase possibility of survival; even if several
perish, many will still survive.
Body covered with tough cuticle which resists digestion by the host
Other equipment that may be added to specimens G, H, I and J to perform the operation
mentioned in 2(a) (i)
Leveling staff
Abney level
Theodolite
Prismatic compass
Gunter's chain/metric 'chain/engineer's chain
Offset staff/pin
Other equipment that may be added to specimens G, H, I and J to perform the operation mentioned in 2(a) (i)
Leveling staff
Abney level
Theodolite
Prismatic compass
Gunter's chain/metric 'chain/engineer's chain
Offset staff/pin
Precaution that should be taken when using specimen J (Garden line)
Do not drag/rub against rough surfaces/edges
Do not pull too hard when taking measurement to avoid damage/snapping
Properly tie to the pole to avoid accidental release when in use and to ensure accurate readings
Must be straight and horizontal for accurate measurements |
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