JAMB Past Questions

JAMB Biology 2015
Questions & Answers

40 questions · Correct answers highlighted · 40 with explanations

40 Total Questions
2015 Exam Year
40 With Explanations
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1
Question 1 of 40
JAMB · Biology · 2015

Which of the following structures is a protective adaptive feature of the Agama lizard to the environment?

A. Nuchal crest
B. Claws
C. Scaly skin
D. Gular fold
Explanation

The scaly skin of the Agama lizard provides protection against predators and harsh environmental conditions, such as extreme heat and dryness in its habitat.

2
Question 2 of 40
JAMB · Biology · 2015

Which of the following adapts an insect for feeding?

A. Waxy cuticle on shoot surface
B. Paired antennae
C. Segmented body
D. Jointed appendages
Explanation

Jointed appendages, such as mandibles and maxillae, are specialized structures in insects adapted for grasping, chewing, or sucking food, directly aiding in feeding.

3
Question 3 of 40
JAMB · Biology · 2015

What is the genotypic ratio from a cross between Yy and Yy?

A. 2Yy:2yy
B. Yy:yy:Yy
C. Yy:2Yy:yy
D. Yy:Yy:2yy
Explanation

A monohybrid cross between Yy and Yy results in a genotypic ratio of 1 YY : 2 Yy : 1 yy, as per Mendelian genetics. The option Yy:2Yy:yy represents this 1:2:1 ratio.

4
Question 4 of 40
JAMB · Biology · 2015

Which of the following is NOT part of the carbon cycle?

A. Organic carbon
B. Decomposition
C. Nitrates formation
D. Photosynthesis
Explanation

Nitrates formation is part of the nitrogen cycle, involving the conversion of nitrogen into nitrates by bacteria. The carbon cycle includes processes like photosynthesis, decomposition, and organic carbon transfer.

5
Question 5 of 40
JAMB · Biology · 2015

In cellular respiration, energy is stored in the form of

A. Heat energy
B. Adenosine diphosphate
C. Adenosine monophosphate
D. Adenosine triphosphate
Explanation

Cellular respiration produces energy stored as adenosine triphosphate (ATP), the primary energy currency in cells, used for metabolic processes.

6
Question 6 of 40
JAMB · Biology · 2015

The principal organ for the manufacture of food in autotrophs is the

A. Root hair
B. Growing root
C. Mature fruit
D. Green leaf
Explanation

The green leaf contains chlorophyll, which captures sunlight to perform photosynthesis, the process by which autotrophs produce food (glucose).

7
Question 7 of 40
JAMB · Biology · 2015

A disease that results from lack of iodine in the diet is

A. Beriberi
B. Scurvy
C. Rickets
D. Goitre
Explanation

Goitre is caused by iodine deficiency, which impairs thyroid hormone production, leading to swelling of the thyroid gland.

8
Question 8 of 40
JAMB · Biology · 2015

The process whereby some organisms with certain favorable features get established in an area is

A. Gene mutation
B. Dispersal
C. Overcrowding
D. Natural selection
Explanation

Natural selection is the process where organisms with traits best suited to their environment survive and reproduce, becoming established in an area.

9
Question 9 of 40
JAMB · Biology · 2015

The rise and fall of ocean water during the day is referred to as

A. Gravity
B. A pull
C. Tide
D. Zone
Explanation

Tides are the periodic rise and fall of ocean water caused by the gravitational forces of the moon and sun acting on Earth’s oceans.

10
Question 10 of 40
JAMB · Biology · 2015

Which of the following is a producer in an aquatic habitat?

A. Nymphaea
B. Diatoms
C. Planarian
D. Similium
Explanation

Nymphaea (water lily) is a producer in aquatic habitats, using photosynthesis to produce energy. Diatoms are also producers, but Nymphaea is the best fit among the options.

11
Question 11 of 40
JAMB · Biology · 2015

The relationship that exists between the shark and Remora is

A. Parasitism
B. Commensalism
C. Saprophytism
D. Symbiosis
Explanation

In commensalism, the Remora benefits by attaching to the shark for food scraps and transport, while the shark is neither harmed nor benefited.

12
Question 12 of 40
JAMB · Biology · 2015

The process of shedding the exoskeleton of an arthropod is known as

A. Ecdysis
B. Star formation
C. Metamorphosis
D. Osmosis
Explanation

Ecdysis is the process by which arthropods, such as insects and crustaceans, shed their exoskeleton to allow for growth.

13
Question 13 of 40
JAMB · Biology · 2015

Which of the following is a major cause of constipation in humans?

A. Lack of roughage
B. Vitamin B
C. Vitamin E
D. Lack of salts
Explanation

Lack of roughage (dietary fiber) reduces bulk in the stool, slowing bowel movements and causing constipation.

14
Question 14 of 40
JAMB · Biology · 2015

In mammals, the organ directly on top of the kidney is the

A. Adrenal gland
B. Prostate gland
C. Pancreas
D. Thyroid gland
Explanation

The adrenal gland is located directly on top of the kidney in mammals, producing hormones like cortisol and adrenaline.

15
Question 15 of 40
JAMB · Biology · 2015

An accurate identification of a rapist can be carried out by conducting a

A. RNA analysis
B. Blood group test
C. Behavioural traits test
D. DNA analysis
Explanation

DNA analysis provides a unique genetic profile, making it the most accurate method for identifying individuals in forensic investigations.

16
Question 16 of 40
JAMB · Biology · 2015

An example of a fish that aestivates is

A. Croaker
B. Lung fish
C. Shark
D. Cat fish
Explanation

Lungfish can aestivate during dry periods by burrowing into mud and breathing air, entering a dormant state to survive drought.

17
Question 17 of 40
JAMB · Biology · 2015

The opening and closing of the stomata are regulated by

A. Respiration
B. Osmosis
C. Diffusion
D. Transpiration
Explanation

Osmosis controls water movement in guard cells, altering their turgidity to open or close stomata, regulating gas exchange and water loss.

18
Question 18 of 40
JAMB · Biology · 2015

Which insect is commonly associated with blackflies as a disease vector?

A. Housefly
B. Mosquito
C. Tsetse fly
D. Blackfly
Explanation

Mosquitoes, like blackflies, are vectors for diseases (e.g., malaria, onchocerciasis) and share similar aquatic larval habitats, making them closely associated.

19
Question 19 of 40
JAMB · Biology · 2015

A crucible of sodium weighed 10g after filling with fresh soil. It is then heated in an oven at 1000°C for 1 hour. After cooling in a desiccator, the weight was 8g. The percentage of water in the soil is

A. 0.8
B. 0.2
C. 0.4
D. 0.6
Explanation

Initial weight = 10g, final weight = 8g. Water weight = 10g - 8g = 2g. Percentage of water = (2g / 10g) x 100 = 20% = 0.2.

20
Question 20 of 40
JAMB · Biology · 2015

The waste product of plants used in the conversion of hide to leather is

A. Alkaloid
B. Resin
C. Tannin
D. Gum
Explanation

Tannin, a plant-derived compound, is used in the tanning process to bind with proteins in animal hides, converting them into leather.

21
Question 21 of 40
JAMB · Biology · 2015

Which of the following is an example of a parasite?

A. Squirrel living in an abandoned nest
B. Mistletoe growing on an orange tree
C. Fungi growing on a dead tree branch
D. Cattle egret feeding on ticks
Explanation

Mistletoe is a parasitic plant that grows on host trees like orange trees, deriving nutrients and harming the host.

22
Question 22 of 40
JAMB · Biology · 2015

A water medium is necessary for fertilization in

A. Conifers
B. Angiosperms
C. Ferns
D. Fungi
Explanation

Ferns require water for fertilization, as their motile sperm swim through a water film to reach the egg.

23
Question 23 of 40
JAMB · Biology · 2015

An example of a sex-linked trait is the

A. Colour of the skin in humans
B. Ability to roll the tongue
C. Possession of facial hair in adult humans
D. Ability to grow long hair in females
Explanation

Facial hair in adult males is a sex-linked trait, influenced by genes on the Y chromosome, which is present only in males.

24
Question 24 of 40
JAMB · Biology · 2015

Which of the following is true of cloning?

A. It is welcomed as an ethical and morally sound science
B. It involves the asexual multiplication of the tissues of the original organism
C. The clone is similar but not exactly like the original organism
D. Only one cell of the original organism is needed to initiate the process
Explanation

Cloning involves asexual reproduction to produce genetically identical copies of an organism, often through tissue multiplication or nuclear transfer.

25
Question 25 of 40
JAMB · Biology · 2015

Which of the following is a primitive respiratory system?

A. Insect
B. Fish
C. Snail
D. Mouse
Explanation

Insects have a primitive respiratory system using tracheae, a network of tubes that deliver oxygen directly to tissues, unlike gills or lungs.

26
Question 26 of 40
JAMB · Biology · 2015

One adaptation shown by hydrophytes in fresh water habitats is the

A. Waxy cuticle on shoot surface
B. Poor development of roots and xylem tissues
C. Well-developed roots and supporting system
D. Leaves reduced to spines
Explanation

Hydrophytes have poorly developed roots and xylem due to abundant water availability, reducing the need for extensive water-absorbing structures.

27
Question 27 of 40
JAMB · Biology · 2015

Which of the following results from diffusion as the principal method of gaseous exchange?

A. Grasshopper
B. Rat spines
C. Lizard
D. Earthworm
Explanation

Earthworms rely on diffusion through their moist skin for gaseous exchange, lacking specialized respiratory organs like lungs or tracheae.

28
Question 28 of 40
JAMB · Biology · 2015

The theory which supports the view that the large muscles developed by an athlete will be passed on to the offspring was proposed by

A. Mendel
B. Darwin
C. Lamarck
D. Pasteur
Explanation

Lamarck’s theory of inheritance of acquired characteristics posits that traits developed during an organism’s life, like large muscles, can be passed to offspring.

29
Question 29 of 40
JAMB · Biology · 2015

The chromosomes of members of the kingdom Monera are within the

A. Nucleoplasm
B. Nucleus
C. Nucleolus
D. Cytoplasm
Explanation

Monera (e.g., bacteria) lack a true nucleus; their genetic material is located in the cytoplasm as a nucleoid region.

30
Question 30 of 40
JAMB · Biology · 2015

The mangrove swamp in Nigeria is restricted to the

A. Sahel savanna
B. Guinea savanna
C. Tropical rainforest
D. Sudan savanna
Explanation

Mangrove swamps in Nigeria are found in the tropical rainforest zones, particularly coastal areas like the Niger Delta, due to high rainfall and tidal influences.

31
Question 31 of 40
JAMB · Biology · 2015

The photosynthetic pigments include

A. Chloroplast and cytochrome
B. Melanin and haemoglobin
C. Chlorophyll and carotenoids
D. Carotenoids and haemoglobin
Explanation

Photosynthetic pigments in plants include chlorophyll (absorbs light for photosynthesis) and carotenoids (accessory pigments that absorb additional wavelengths).

32
Question 32 of 40
JAMB · Biology · 2015

The highest level of ecological organization is the

A. Ecosystem
B. Niche
C. Biosphere
D. Population
Explanation

The biosphere is the highest level of ecological organization, encompassing all ecosystems and living organisms on Earth.

33
Question 33 of 40
JAMB · Biology · 2015

A biotic factor which affects the distribution and abundance of organisms in a terrestrial habitat is

A. pH
B. Competition
C. Temperature
D. Light
Explanation

Competition, a biotic factor involving interactions among living organisms, influences the distribution and abundance of species in a terrestrial habitat.

34
Question 34 of 40
JAMB · Biology · 2015

The eye defect that arises because the cornea is not curved smoothly is

A. Astigmatism
B. Short-sightedness
C. Long-sightedness
D. Presbyopia
Explanation

Astigmatism results from an unevenly curved cornea, causing blurred or distorted vision at all distances.

35
Question 35 of 40
JAMB · Biology · 2015

Which of the following organisms is an example of a saprophyte?

A. Mushroom
B. Fern
C. Moss
D. Pea plant
Explanation

Mushrooms are saprophytes, feeding on dead organic matter by secreting enzymes to decompose it, unlike ferns, mosses, or pea plants, which are photosynthetic.

36
Question 36 of 40
JAMB · Biology · 2015

Which of the following processes is responsible for the movement of water up the stem of a plant?

A. Diffusion
B. Osmosis
C. Transpiration pull
D. Capillarity
Explanation

Transpiration pull drives water movement up the stem, as water evaporation from leaves creates a suction force that pulls water through the xylem.

37
Question 37 of 40
JAMB · Biology · 2015

Which of the following is a characteristic feature of the tropical rainforest?

A. Low rainfall
B. High humidity
C. Sparse vegetation
D. Extreme cold
Explanation

Tropical rainforests are characterized by high humidity, supporting dense vegetation and high biodiversity due to abundant rainfall.

38
Question 38 of 40
JAMB · Biology · 2015

The process of nitrogen fixation in the soil is carried out by

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

Nitrogen-fixing bacteria, such as Rhizobium in root nodules of legumes, convert atmospheric nitrogen into compounds usable by plants.

39
Question 39 of 40
JAMB · Biology · 2015

Which of the following animals is an example of a hermaphrodite?

A. Earthworm
B. Cockroach
C. Lizard
D. Frog
Explanation

Earthworms are hermaphrodites, possessing both male and female reproductive organs, allowing mutual fertilization during mating.

40
Question 40 of 40
JAMB · Biology · 2015

Which blood group is known as the universal donor?

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

Blood group O is the universal donor because it lacks A, B, and Rh antigens, making it compatible with all other blood groups during transfusion.

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