Biology Paper 3 (Practical), WASSCE (SC), 2017

Question 2

LIST OF SPECIMENS

Specimen A - Winged termite.
Specimen B - Maggot (freshly procured).
Specimen C - Adult butterfly with open wings.
Specimen D - Caterpillar (freshly procured).
Specimen E - Grasshopper.
Specimen F - Carrot with leaves attached (freshly procured).
Specimen G - Irish potato.
Specimen H - Adult mosquito.
Specimen J - Adult cockroach.
Specimen Q - Housefly.
Specimen R - Earthworm (dead, freshly procured in a Petri dish containing water).
Specimen S - cross section of unripe mango fruit.
Specimen T - Cross section of tomato fruit.

 

Study specimens F and G carefully and use them to answer questions 2(a) and 2(b).
  1. (a) State three observable features of biological importance in:
    (i) specimen F; [3 marks]
    (ii) specimen G. [3 marks]
  2. (i) Classify specimens F and G as either stem tuber or root tuber. [2 marks]
    (ii) Give two reasons each for the answers in 2(b)(i). [4 marks]
  3. Study specimens H and J carefully and use them to answer questions 2(c) and 2(e).
  4. Classify specimens H and J into the class to which both belong. [1 mark]
  5. (i) State four observable differences between specimens H and J. [4 marks]
    (ii) State four observable similarities between specimens H and J. [4 marks]
  6. (i) State the feeding habits of each of specimens H and J. [2 marks]
    (ii) Name two observable features used for feeding in specimen J. [2 marks]

Observation

This question was poorly attempted. Some candidates could not state the observable features of biological importance of specimen F. Some candidates could state the observable similarities between specimens H and J. Most candidates could not also state the feeding habits of specimen H but could state for specimen J.

 The expected answers are:

 

  1. Observable features of biological importance in

    Specimen F/Carrot

    - Main root/tap root/swollen/root tuber;

    - Presence of lateral roots;

    - Presence of short stem (green);

    - Presence of foliage leaves;

    - Part of main root tapering.

    Specimen G/Irish potato

    - Swollen stem/stem tuber;

    - Bud(s)/eye;

    - Lenticels;

    - Scale leaf

    - Adventitious root(s).

  2. (i) Classification of

    Specimen F/Carrot
    Root tuber

    Specimen G/Irish potato
    Stem tuber

    (ii)Reasons for classificationSpecimen F/Carrot

    - Swollen tap root;

    - Lateral roots present;

    - Has a reduced stem (above the swollen tap root).

    Specimen G/Irish potato

    - Swollen stem/tuber;

    - presence of bud(s)/eye;

    - presence of scale leaves/leaf;

    - presence of lenticel(s).

  3.  

  4. Class of specimens H and J
    Insecta
  5.  

  6. (i) Observable differences between specimens H and J

    (ii) Similarities between specimens H/adult mosquito and J/adult cockroach

    - Presence of a pair of compound eyes;

    - Body is divided into three divisions/head, thorax and abdomen;

    - Three pairs of/six (walking) legs;

    - Presence of jointed appendages;

    - Presence of a pair of membraneous wings;

    - Presence of a pair of antennae;

    - Both have exoskeleton made of chitin;

    - Segmented body.

  7. (i)Feeding habit of
    Specimen H/adult mosquito
    Piercing and sucking

    Specimen J/adult cockroach
    Biting and chewing

    (ii)Observable features used for feeding in specimen J/adult cockroach
    Mandible; maxillae; labium; labrum