A student trying to find out the order in which organisms appear on a cleared plot is studying one of the following

A. Ecosystem

B. Food chain

C. Food web

D. Succession

E. Community

An organism X lives entirely on the waste products in another organism Y. In this association X is a

A. symbiont

B. commensal

C. saprophyte

D. parasite

E. epiphyte

The tips of some rice seedlings were cut off while some were left intact. Both were covered with a container which had not only one small hole to allow light through. After twenty-four hours it was observed that

A. the cut tips was bent away from the light

B. the cut tips bent towards source of light

C. the intact tips bent away from the light

D. the intact tips bent towards the light

E. both tips bent away from light

If three 30 cm lengths of glass tubes are tightly packed with clay, sand and loamy soils respectively and then stood in a beaker of water for one week, the level of water will be

A. lowest in the tube with clay

B. the same in all tubes

C. lowest in the tube with loamy soil

D. highest in the tube with sandy soil

E. lowest in the tube with sandy soil

If a baby is a female, her mother's ovum must have been fertilized by a sperm carry the chromosome

A. X

B. XY

C. XX

D. YY

E. Y

Leguminous plants, e.g Mucana, are usually planted in cultivated farmlands because they

A. enrich the soil with phoshates

B. provide animals with food

C. enrich the soil with organic nitrogen

D. protect the soil from being over-heated

E. protect the micro organisms in the soil

During thunderstorms the energy of lightning discharge causes

A. oxygen and nitrogen to combine

B. more carbon dioxide to be formed

C. nitrites to be converted to nitrates

D. nitrates to be converted to nitrogen

E. death

A few grams of dried soil were first heated until red hot and then further heated until no more smoke was released. This experiment was to determine

A. amount of water in soil

B. percentage of water in soil

C. presence of humus in soil

D. resistance of laterities to heat

E. release of smoke from the soil

Oxygen from the atmosphere reaches the mammalian blood stream through one of the path indicated below. Indicate the correct path, a = mouth, b = trachea, c = bronchiole, d = nostril, e = bronchus, f = alveoli

A. a → b → e → f → d

B. b → d → f → e → c

C. d → b → e → c → f

D. b → a → f → e → c

E. f → e → c → d → c

Below are some group of diseases. Which group of diseases is caused by bacteria?

A. Tuberculosis, smallpox

B. Gonorrhoea, measles

C. Tuberculosis, polio

D. Sleeping sickness, measles

E. Syphilis, gonorrhoea