PART I
ANSWER ALL THE QUESTIONS
1 (a)Specimens a A, B and C are different liquids of food materials. Cary out the Following tests to identify the food Contents Of Specimens A, B and C.
Wash the test-tubes after each use to avoid contaminating the next sample.
Record your tests and observations shown in the table below
|
TESTS |
OBSERVATIONS |
INFERENCE |
(i) To a small portion of a specimen A, add four drops of reagents F, Shake the mixture and heat gently for a few minutes. Record your observations and inference.
(ii) To a small portion of a specimen A, add three drops of reagent D, shake the mixture and heat gently for a few minutes. Allow the mixture to cool. Record your observations and inference.
(ii) To a small portion of a specimen A, add three drops of reagent H, shake the mixture and heat gently for a few minutes. Allow the mixture to cool. Record your observations and inference.Leave this mixture in the test tube.
(iv) To the resulting mixture in (ii) above, add three drops of reagent E, shake the mixture and heat gently for a few minutes. Allow the mixture to cool. Record your observations and inference.
(v) To a small portion of specimen B, add three drops of reagents G, Shake the mixture. Record your observations and inference.
(vi) Take a strip of the litmus paper provided, dip the tip of the paper into Specimen C, Record your observations and inference of the reaction on the litmus paper.
(b)(i) Give one example each of the food contents identified in specimens A and B (ii) State two uses each, of the food contents identified in specimens A, B and C to man.
(c) Name the primary source of the food contents identified in specimens A and B and a natural source of specimen C.
2. (a) (i) State three observable I and J without reasons.(ii) Name the habitats of specimens I and J (b) State three observable structural adaptations for movement possessed by specimen J (c)(i) Name one respiratory organs of specimen l and J three respiratory organs of specimen J. (ii) State four common features of the respiratory organs of specimens I and J(d) Cut off one of the opercula of specimens I with the scalpel or small knife to expose the respiratory organ. Make a labeled drawing about 8 cm to 10cm long of the head region up to the end of the pectoral fin only to show its structures.
PART II
ANSWER ALL THE QUESTIONS
3. (a) Observing specimen K, copy and complete the table below
|
Specimen |
Floral Parts | Number of Colored Parts | Free or Fused or united |
Essential or Non-essential |
| K |
Sepals/calyx Petals/corolla Stamens Stigma |
b. Cut Specimen K longitudinally into iwo halves. Observe the halved specimen K and use it to answer Questions (b) (i) – (iv) . (i) What is the symmetry of specimen K (ii) Classify Specimen K in relation to its reproductive structures. structures. (iii) Name tne type of placentation specimen K (iv) What type of ovary does specimen K have?
c. Detach the sepals and petals of the longitudinal section of the Specimen and make a labeled diagram of 10cm to 12cm long to illustrate the features of the remaining part of specimen k
d. Name the agent of pollination of specimen K . (ii) Give one example of the agent of pollination of specimen K (iii) State four adaptive features of specimen K that attracts the agent you have mentioned.
Explanation
|
Test/ Method |
Observation |
Inference |
|
(i) To a small portion of specimen A, add few drops of reagent F and heat gently. |
A brick-red/ orange precipitate is observed.
|
Indicates presence of reducing sugar e.g glucose, fructose and galactose |
|
(ii) To a small portion of specimen A add few drops of reagent D. |
blue- black /black color is observed. |
Indicates presence of starch |
|
(iii) To a small portion of specimen A, add small quantity or reagent H, No color change/No change. heat gently for a few minutes and allow to cool. |
No red precipitate/ No precipitate. No color change/ No change |
No food content detected |
|
iv) To specimen A treated with reagent H heated, add small quantity of reagent E, heat for a few minutes and allow to cool |
A blue precipitate The blue ppt when heated turn brick red /red Or Brick-red orange precipitate obtained. |
This indicates presence of starch/ complex carbohydrate or has been hydrolyzed to simple reducing Sugar Or indicates presence of simple reducing sugar. |
|
(V) To a small portion of specimen B, add small portion of reagent G |
Violet/purple color is obtained |
Indicates presence of protein |
|
(vi)Litmus dipped in specimen C |
No color change/ No change. Color remain the same. it is neutral to litmus paper. |
Neutral solution/Distilled water/Liquid solvent water present/ no change |
(b) (i) Examples of food contents in specimens A and B: (1) Specimen A: Reducing sugar/glucose/fructose/galactose e.g. Fruits/oranges/grapes/mango/tomato; Maltose or lactose, e.g. banana /pineapple/lime/coconut milk; Starch,
e.g. rice /grains/cereal/ yam/potato/any correctly named food containing starch.
Specimen B-Protein e. g meat fish/egg/ milk/ chicken/Cray fish/ beans/ legumes.
(i) Importance of specimen A, B and C to man: (1) Reducing sugar provides energy, maintains body temperature, produces heat for oxidation and produces warmth. (2) Starch provides energy, heat or warmth which can be converted and stored as fat and for industrial uses, e.g alcohol productions and laundry.
(3)Protein is for growth body building, for repairs or replacement of worn out or damaged cells/tissues/blood cells, synthesis or enzymes or hormones and for red blood making.
(4) Water is used as solvent, medium for reactions of particles, Sustenance or lie, cooking/washing/drinking/domestic use, maintenance of body temperature, medium for digestion
(C)(i) The Primary source of food contents identified in specimen A and B is Plant/green plant/producers. (ii) Natural Source of specimen C is spring/stream/river/sea/rain/lake/ocean/pond.
2. (a) Specimen I - is a bony fish/Tilapia; Specimen J is a toad/frog/bufo. (ii) Habitat of specimen I is Aquatic; Habitat of specimen J is Terrestrial/land, Fresh water or partial aquatic fresh water.
(b) Structural adaptations for movement by specimen J: Short fore-limb (in the four digits for landing); Long and muscular nind - limbs (for hopping/Jumping); Webbed digits/toes of the hind - limbs (for swimming); Streamlined body (for movement in water). (d) Respiratory organs of specimens I and J: Specimen I = gill/gill only; Specimen J bucal cavity/mouth, Skin, Lungs, Nostril.
(C)(i) Common features of the respiratory organs of specimen l and J: Thin surface/layer. Large/broad suce area, Moist/moistened/wet surface,
-Surface vascularized/ richly supplied with blood vessels, numerous tnin blood vessels.
| Specimen | Floral | Number of Parts | Color | Free/Fuse united |
Essential or Non-essential |
|
K (Hibiscus flower ) |
Sepals/calyx | 5 | Green | united/fused |
Non-essential |
| Petals/corolla | 5 | Red/Pink | Free |
Non-essential |
|
| Stamens | numerous/ / uncountable Above 10 many /plenty | Red/Pink/white/ yellow | united/fused |
Essential |
|
| Stigma | 5 | Red/Pink | free |
Essential |