1. You are provided with solutions P, Q,R,S,T and specimen U. You are required to carry out tests on the solutions using specimen U, following the procedure provided.

Procedure
a) i) Label five test tubes as P, Q, R, S and T and add 10cm3 of the corresponding solution to each test tube.
   ii) Using a cork borer cut out 10 pieces from specimen U, each measuring 4cm long.
  iii) Put two pieces of U, made in (a) (ii) into each test tube and leave the set-up for one hour.
  iv) After one hour, carefully pour out all liquid from test tube P into a measuring cylinder leaving behind the pieces of U in the test tube.
  v) Record the final volume of the liquid from test tube P in Table 1.
  vi) Repeat te steps (iv) and (v) for the remaining test tubes to obtain the final volume of the liquids from test tubes Q, R, S and T. Record each of them in Table 1.

Table 1

b) Work out the change in volume in each test tube and complete Table 1 above.
c) Draw a histogram of change in volume against solutions P,Q, R, S and T on a graph paper.
d) Using your histogram explain the changes in volume of each solution P,Q,R,S,T.
e) From your results, estimate the water potential of the cell sap of specimen U. Give a reason for your answer.

2. You are provided with specimens W, X, Y and Z.
a) Using a hand lens, examine specimen Z and state how the features of its head are suited for its role in the community it lives.

b) Examine the wings of specimen W and Y using a hand lens and state three structural differences between them in Table 1.

Table 1

c) i) Observe the tibia and tarsus of each specimen using the low power of a microscope. State two descriptive features on the tibia and tarsus of each specimen in Table 2.

    ii) Observe the abdominal appendages on each of the specimens and state your observation in Table 2.

d) Using the features on the tibia alone, construct a dichotomous key to identify the specimens.
e) In the space below; draw and label the last three segments of the tarsus of the hind limbs of specimens W and X, when viewed under low power of a microscope.

3. You are provided with specimen M which is freshly killed.
     a) i) Name the class to which the specimen belongs.
        ii) Examine the specimen and give five characteristics of the class named in (a) (i) which can be observed on the specimen.

b) Open up the specimen, clear the pectoral muscles of the thorax to expose the rib cage and structures in the neck region. Draw and label the rib cage and structures located in the neck region of the specimen.

c) i) Cut out the alimentary canal and dissect the prosterior part of the specimen to expose blood vessels which drain blood from structures used for excretion and left hind limb, back the heart.
   ii) Continue to dissect the anterior parts of the specimen to expose blood vessels which take away blood from the left head region, left thoracic region and left fore limb back to the heart.

Draw and label what is displayed in (c) (i) and (c) (ii) excluding the heart, in one drawing.

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