JAMB Past Questions

JAMB Biology 2012
Questions & Answers

40 questions · Correct answers highlighted · 40 with explanations

40 Total Questions
2012 Exam Year
40 With Explanations
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1
Question 1 of 40
JAMB · Biology · 2012

The respiratory structure in insects is the

A. Lung
B. Trachea
C. Gill
D. Heart
Explanation

Insects use a tracheal system with spiracles for respiration, unlike lungs or gills.

2
Question 2 of 40
JAMB · Biology · 2012

The organelle responsible for heredity is

A. Mitochondrion
B. Endoplasmic reticulum
C. Golgi apparatus
D. Nucleus
Explanation

The nucleus contains DNA, which carries hereditary information.

3
Question 3 of 40
JAMB · Biology · 2012

The most evolutionarily advanced animal among the following is

A. Liver fluke
B. Earthworm
C. Snail
D. Cockroach
Explanation

Cockroaches, as insects, have complex structures, making them more advanced.

4
Question 4 of 40
JAMB · Biology · 2012

The lowest category in biological classification is

A. Class
B. Species
C. Family
D. Genus
Explanation

Species is the most specific taxonomic rank in classification.

5
Question 5 of 40
JAMB · Biology · 2012

Plants showing secondary growth are typically

A. Thallophytes
B. Pteridophytes
C. Monocotyledons
D. Dicotyledons
Explanation

Dicotyledons have vascular cambium for secondary growth.

6
Question 6 of 40
JAMB · Biology · 2012

Fungi are distinct eukaryotes mainly because they

A. Produce spores
B. Lack chlorophyll
C. Have fruiting bodies
D. Reproduce sexually and asexually
Explanation

Fungi lack chlorophyll, distinguishing them from photosynthetic plants.

7
Question 7 of 40
JAMB · Biology · 2012

An arthropod destructive in its early life stage is

A. Butterfly
B. Mosquito
C. Bee
D. Millipede
Explanation

Butterfly larvae (caterpillars) damage plants, unlike other options.

8
Question 8 of 40
JAMB · Biology · 2012

An animal body divisible into identical parts along any axis is

A. Radially symmetrical
B. Bilaterally symmetrical
C. Asymmetrical
D. Symmetrical
Explanation

Radial symmetry allows identical halves in any plane, e.g., jellyfish.

9
Question 9 of 40
JAMB · Biology · 2012

Which animal possesses mammary glands?

A. Dogfish
B. Whale
C. Shark
D. Catfish
Explanation

Whales, as mammals, have mammary glands for nursing.

10
Question 10 of 40
JAMB · Biology · 2012

The evolutionary link between birds and reptiles is

A. Feathers
B. Beak
C. Skeleton
D. Scales
Explanation

Birds and reptiles share scales, a common ancestral trait.

11
Question 11 of 40
JAMB · Biology · 2012

Countershading in animals helps them to

A. Fight enemies
B. Remain undetected
C. Warn enemies
D. Attract mates
Explanation

Countershading camouflages animals by balancing light and shadow.

12
Question 12 of 40
JAMB · Biology · 2012

Which plant structure lacks a waterproof cuticle?

A. Leaf
B. Stem
C. Root
D. Shoot
Explanation

Roots lack a cuticle to facilitate water absorption.

13
Question 13 of 40
JAMB · Biology · 2012

In the male mammalian reproductive system, the passage for urine and semen is

A. Urethra
B. Ureter
C. Bladder
D. Seminal vesicle
Explanation

The urethra serves as a dual passage in males.

14
Question 14 of 40
JAMB · Biology · 2012

A micronutrient required in minute quantities for plant growth is

A. Copper
B. Potassium
C. Phosphorus
D. Sodium
Explanation

Copper is a micronutrient needed in trace amounts.

15
Question 15 of 40
JAMB · Biology · 2012

Which organism is both parasitic and autotrophic?

A. Sundew
B. Loranthus
C. Rhizopus
D. Tapeworm
Explanation

Sundew photosynthesizes and traps insects, combining autotrophic and parasitic traits.

16
Question 16 of 40
JAMB · Biology · 2012

Hydrochloric acid in the stomach during digestion

A. Neutralizes bile
B. Coagulates milk protein
C. Stops ptyalin action
D. Breaks food particles
Explanation

HCl creates an acidic environment, stopping ptyalin (salivary amylase).

17
Question 17 of 40
JAMB · Biology · 2012

Which is a polysaccharide?

A. Glucose
B. Sucrose
C. Maltose
D. Cellulose
Explanation

Cellulose is a complex carbohydrate made of glucose units.

18
Question 18 of 40
JAMB · Biology · 2012

In the kidney, ultrafiltration occurs in the

A. Uriniferous tubule
B. Bowman’s capsule
C. Loop of Henle
D. Renal tubule
Explanation

Bowman’s capsule filters blood to form glomerular filtrate.

19
Question 19 of 40
JAMB · Biology · 2012

Secondary thickening in plants involves

A. Collenchyma and xylem
B. Vascular and cork cambium
C. Vascular cambium and sclerenchyma
D. Cork cambium and sclerenchyma
Explanation

Vascular and cork cambium drive secondary growth in plants.

20
Question 20 of 40
JAMB · Biology · 2012

A fruit developing from a single carpel is

A. Okro
B. Tomato
C. Bean
D. Orange
Explanation

Beans form from a single carpel, unlike multiple-carpel fruits.

21
Question 21 of 40
JAMB · Biology · 2012

Plant growth is artificially stimulated by

A. Gibberellin
B. Kinin
C. Abscisic acid
D. Ethylene
Explanation

Gibberellin promotes stem elongation and growth.

22
Question 22 of 40
JAMB · Biology · 2012

The autonomic nervous system controls

A. Voluntary muscles
B. Heart beat
C. Tongue
D. Hands
Explanation

The autonomic system regulates involuntary actions like heart rate.

23
Question 23 of 40
JAMB · Biology · 2012

Temperate plants can grow in tropical zones in

A. Rain forest
B. Guinea savanna
C. Sudan savanna
D. Montane forest
Explanation

Montane forests have cooler climates suitable for temperate plants.

24
Question 24 of 40
JAMB · Biology · 2012

The water cycle is maintained by

A. Evaporation alone
B. Evaporation and condensation
C. Condensation alone
D. Transpiration and respiration
Explanation

Evaporation and condensation drive the water cycle.

25
Question 25 of 40
JAMB · Biology · 2012

Organisms in estuarine habitats adapt to

A. Temperature fluctuations
B. Low salinity
C. Salinity fluctuations
D. Phytoplankton diet
Explanation

Estuarine organisms tolerate varying salinity levels.

26
Question 26 of 40
JAMB · Biology · 2012

Sunken stomata and leaf spines are adaptations for

A. Tropical rainforest
B. Mangrove swamps
C. Desert
D. Montane forest
Explanation

These features reduce water loss, typical in desert plants.

27
Question 27 of 40
JAMB · Biology · 2012

Animals that rely solely on metabolic water are

A. Forest arboreal dwellers
B. Desert dwellers
C. Forest-ground dwellers
D. Rainforest dwellers
Explanation

Desert animals use metabolic water to survive scarce water.

28
Question 28 of 40
JAMB · Biology · 2012

The first colonizers of bare rock are

A. Mosses
B. Ferns
C. Lichens
D. Fungi
Explanation

Lichens break down rock as pioneer species.

29
Question 29 of 40
JAMB · Biology · 2012

The carrying capacity of a habitat is reached when population growth

A. Increases slowly
B. Slows down
C. Remains steady
D. Decreases rapidly
Explanation

Growth slows as resources limit population size.

30
Question 30 of 40
JAMB · Biology · 2012

Abiotic factors controlling human population include

A. Disease and famine
B. Space and rainfall
C. Flooding and earthquake
D. Temperature and disease
Explanation

Flooding and earthquakes are abiotic, unlike biotic factors like disease.

31
Question 31 of 40
JAMB · Biology · 2012

An indigenous method to maintain soil fertility is

A. Burning farms
B. Monocropping
C. Annual fertilizers
D. Crop rotation
Explanation

Crop rotation and shifting cultivation restore soil nutrients.

32
Question 32 of 40
JAMB · Biology · 2012

Water-borne diseases include

A. Gonorrhoea and poliomyelitis
B. Typhoid and syphilis
C. Tuberculosis and cholera
D. Typhoid and cholera
Explanation

Typhoid and cholera are transmitted via contaminated water.

33
Question 33 of 40
JAMB · Biology · 2012

A graph showing cassava plant height illustrates

A. Highest frequency at 2m
B. Discontinuous variation
C. Continuous variation
D. Total yield
Explanation

Height is a continuously varying trait, shown in the graph.

34
Question 34 of 40
JAMB · Biology · 2012

The approximate height of most cassava plants is

A. 1.6m
B. 1.8m
C. 1.9m
D. 2.0m
Explanation

The graph’s peak indicates most plants are around 1.6m.

35
Question 35 of 40
JAMB · Biology · 2012

The primary source of energy in an ecosystem is

A. Decomposers
B. Consumers
C. Producers
D. Sunlight
Explanation

Sunlight drives photosynthesis, the base of energy flow.

36
Question 36 of 40
JAMB · Biology · 2012

Which blood group is a universal donor?

A. A
B. B
C. AB
D. O
Explanation

Group O lacks antigens, making it compatible with all blood types.

37
Question 37 of 40
JAMB · Biology · 2012

The process of nitrogen fixation is carried out by

A. Fungi
B. Bacteria
C. Algae
D. Protozoa
Explanation

Nitrogen-fixing bacteria convert atmospheric nitrogen into usable forms.

38
Question 38 of 40
JAMB · Biology · 2012

The structure that anchors a fetus to the placenta is the

A. Amnion
B. Umbilical cord
C. Chorion
D. Allantois
Explanation

The umbilical cord connects the fetus to the placenta for nutrient exchange.

39
Question 39 of 40
JAMB · Biology · 2012

Which hormone regulates blood sugar levels?

A. Adrenaline
B. Thyroxine
C. Insulin
D. Cortisol
Explanation

Insulin lowers blood sugar by promoting glucose uptake.

40
Question 40 of 40
JAMB · Biology · 2012

The type of reproduction in Amoeba is

A. Sexual
B. Binary fission
C. Budding
D. Conjugation
Explanation

Amoeba reproduces asexually by binary fission, splitting into two.

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