Correct Answer: B. crude

Explanation

Refined; elegant and cultured in appearance, manner, or taste.

Crude; in a natural or raw state; not yet processed or refined.

Explanation

(a) The main ore of tin is cassiterite or tin stone, (SnO\(_2\))

(b) SnO\(_{(s)}\) + 2C\(_{(s)}\) \(\to\) Sn\(_{(l)}\) + 2CO\(_{(g)}\)

(c) Bronze (Cu and Sn); Soldier (Pb and Sn)

Correct Answer: B. ascertain the amount of profits or losses for each department

Explanation

The main objectives of departmental accountingare: To check out an interdepartmental performance. To evaluate the performance of the department with the previous period result. The gross profit of eachdepartment can be ascertained.

Explanation

a. (i) Type of genetic cross: Dihybrid

(ii) Reason for answer: Two characters are involved in the cross/involves two characters separable in inheritance.

b. (i) Phenotype of F1: Tall and Red.

(ii) Genetic Diagram

Let T represent the gene for Tallness;

t represent the gene for Dwarfism;

R represent the gene for Red;

r represent the gene for White.

OR

Parental genotype TtRr X TtRr

Crosses of parental genotypes

Tall and Red - 9

Tall and White - 3

Dwarf and Red - 3

Dwarf and White - 1

Parental genotype

Parental gametes (TR, Tr, tR, tr) shown

Correct Crosses of parental gamete

Phenotypic ratio 9:3:3:1

(iii) Calculation of Tall and White flowers in F2

(3/16) x (160/1) = 30

Correct Answer: A. catalogue

Correct Answer: A. Knife

Correct Answer: D. Ezekiel

Explanation

a. Features of the small intestine that increase the rate of absorption of digested food

- Ridges/furrows on inner linings;

- Small finger-like projections/villi;

- Minute projections/microvilli on the villi;

- Thin epithelial lining of the villi;

- Highly vascularised/well supplied with blood;

- Intestine is long/it has a large surface area.

b. Fate of glucose formed in a plant during photosynthesis

- Glucose combines with Nitrogen/Sulphur/Phosphorus to form proteins for growth;

- Glucose is stored as starch;

- Glucose is oxidised to form carbon dioxide/water/energy in respiration;

- Glucose is also converted into lipids/cellulose which is stored.

c. Mode of feeding of

(i) Euglena

- Exhibits both autotrophic and heterotrophic modes of nutrition;

- In autotrophic mode of feeding, the chlorophyll in its stellate chloroplast absorbs sunlight energy;

- And the dissolved carbon dioxide in the pond water diffuses into the cell of Euglena;

- Inside the chloroplast, the absorbed solar energy/sunlight is used in the synthesis of glucose from water and carbon dioxide;

- Glucose is converted into starch and stored in the paramylum granules;

- In heterotrophic mode of feeding, it takes in organic matter/diatoms e.t.c.;

- Through the gullet;

- And digests it in the reservoir.

(i)Spirogyra

- Manufactures its own food through photosynthesis;

- Its spiral chloroplast/chlorophyll absorbs the sunlight energy;

- It absorbs carbon dioxide from water/its environment to manufacture food;

- The manufactured food is used;

- while the rest/excess is stored in its pyrenoid in the form of starch;

d. Characteristics of an Estuarine Habitat

- It is shallow;

- It has a high level of nutrients;

- Salinity/pH/O2 level fluctuates;

- Turbidity is high during rainy season;

- It is affected by tides;

- Species diversity is low;

- Muddy/soft soil/substratum

d. Differences between an aquatic and terrestrial habitat

Correct Answer: D. Badr and Uhud.

Correct Answer: C. Simeon