NECO Biology Past Questions & CBT Practice

Liver destroys old red blood cells to produce digestive substance called

1. A.amalyse
2. B.bile
3. C.insulin
4. D.lipase✓ Correct
5. E.rennin

Why does the treatment of cotton fabrics with dilute acids weaken the materials?

1. A.Cotton is hydrolysed completely to glucose
2. B.The fabrics are soluble in dilute acids✓ Correct
3. C.The molecular chains are partially broken
4. D.The molecular chain length f the fabric increases
5. E.The thread holding the fabric together Is completely destroyed.

The following are examples of synchronous communication, except?

1. A.A.  blogs
2. B.B. Google talk
3. C.C. phone
4. D.D. video conferencing
5. E.E. yahoo messenger✓ Correct

To keep a lorry moving at a constant speed v, requires power p, from the engine. The force provided by the engine is

1. A.$\frac{1}{2}$v
2. B.pv
3. C.$\frac{p}{v}$✓ Correct
4. D.pv2
5. E.$\frac{p}{v^2}$

The boiling point of water is higher than the boiling point of ethanol because

1. A.the bonding in water is electrovalent (ionic) whereas the bonding in ethanol is convalent
2. B.the hydrogen bonding between water molecules is stronger than the hydrogen bonding between ethanol molecules
3. C.water has a higher lattice energy than ethanol.✓ Correct
4. D.water has hydrogen bonding between its molecules but ethanol has no hydrogen bonging between its molecules;
5. E.water is a better solvent than ethanol.

When the same amount of current, I is passed through different wires under the same conditions, the rates of production of heat are

1. A.directly proportional to I
2. B.directly proportional to the resistances of the wires
3. C.directly proportional to the square of the resistances of the wires
4. D.inversely proportional to I✓ Correct
5. E.inversely proportional to the resistance of the wires

20 cm3 of 0.09 mol dm3 solution of tetraoxosuiphate (Vi) acid requires 30cm3 of sodium hydroxide solution for complete neutralization. The molar concentration of sodium hydroxide is [H = 1; S = 32; 0 = 16; Na = 23]

1. A.0.03 mol dm3
2. B.0.12 mol dm3
3. C.0.27 mol dm3✓ Correct
4. D.0.45 mol dm3
5. E.0.90 mol dm3

Express the quotient of 0.422 and 0.004 in standard form

1. A.1.055 × 102
2. B.10.55 × 101
3. C.105 × 100
4. D.10.55 × 10-1✓ Correct
5. E.1.055 × 10-2

The reaction C2H6 → C2H + H2 is known as

1. A.dehydration
2. B.dehydrogenation
3. C.displacement✓ Correct
4. D.hydrogenation
5. E.reduction

He was instructed to catch the thief dead or ______.

1. A.alive
2. B.deceased✓ Correct
3. C.killed
4. D.living
5. E.unconscious