JAMB Biology 2019
Questions & Answers

A student might incorrectly choose thin fur or small eyes, assuming those relate to desert survival, but the correct choice is large ears because they dissipate high temperatures as a structural adaptation for camels. Common mistake: confusing temperature regulation mechanisms in desert animals.

Students might mistakenly select phototropism or thigmotropism thinking of general plant responses, but the correct answer is geotropism since it guarantees the downward soil growth driven by gravity. Common mistake: mixing up light and gravity stimuli in plant tropisms.

An examinee might incorrectly select an eagle or a cheetah due to their prominent physical adaptations, but the correct option is the mole because its underground lifestyle relies on strong, clawed forelimbs for digging alongside reduced eyes. Common mistake: overlooking specialized subterranean adaptations.

A student might incorrectly think the primary purpose is to anchor the plant or store food, but root hairs are specifically responsible because they increase the surface area for water and nutrient absorption from the soil. Common mistake: confusing general root functions with the specific role of root hairs.

An examinee might mistakenly choose a ball-and-socket joint, but the knee is correctly classified as a hinge joint because it permits movement mainly in one plane through flexion and extension. Common mistake: mixing up the range of motion in major skeletal joints.

A student might incorrectly pick pseudopodium or cilium thinking of other microscopic locomotion structures, but Euglena uses a flagellum, which is a whip-like structure for movement in aquatic environments. Common mistake: confusing flagella with cilia in unicellular organisms.

An examinee might mistakenly select plasma or white blood cells, but red blood cells are the correct choice because they contain hemoglobin to bind and transport oxygen throughout the body. Common mistake: assuming all blood components share the same transport function.

A student might incorrectly choose high rainfall or dense vegetation, but low rainfall is the correct factor because it restricts plant growth and characterizes the distribution of deserts. Common mistake: confusing the causes of desert biomes with lush environments.

An examinee might mistakenly select fever and chills or skin discoloration as general illness signs, but a persistent cough with blood is correct because lung damage from Mycobacterium tuberculosis leads to this specific symptom. Common mistake: overlooking the hallmark respiratory symptom of tuberculosis.

A student might incorrectly pick skin or lungs, but gills are the correct answer since fish use them to release carbon dioxide and extract oxygen from water as their primary gas exchange site. Common mistake: applying mammalian respiratory organs to aquatic animals.

An examinee might mistakenly choose photosynthesis, which removes carbon, but respiration is correct because living organisms release carbon dioxide into the atmosphere to complete the carbon cycle. Common mistake: confusing the directions of carbon movement in photosynthesis versus respiration.

A student might incorrectly select high salinity or low oxygen levels, but the presence of floating plants is correct as water lilies thrive in this low-salinity freshwater environment. Common mistake: assuming freshwater habitats lack specialized plant life.

An examinee might mistakenly choose Plasmodium vivax or Vibrio cholerae, but Trypanosoma brucei is the correct parasite responsible for sleeping sickness and is transmitted by the tsetse fly. Common mistake: mixing up the pathogens responsible for vector-borne tropical diseases.

A student might incorrectly pick glucose or water, but chlorophyll is the correct molecule because it absorbs light energy needed to drive glucose synthesis during photosynthesis. Common mistake: confusing the energy absorber with the products or reactants of photosynthesis.

An examinee might mistakenly select oxygen or nitrogen, but methane is the correct choice because it acts as a greenhouse gas that traps atmospheric heat and contributes to global warming. Common mistake: assuming major atmospheric gases like nitrogen and oxygen are greenhouse gases.

A student might incorrectly pick Hydra or Sponge which have more complex tissue levels, but Paramecium has a cellular level of organization as a unicellular organism handling all functions within one cell. Common mistake: confusing unicellular organization with multicellular tissue systems.

An examinee might mistakenly choose budding or binary fission, but conjugation is correct because Spirogyra undergoes this sexual reproduction method where gametes from two filaments fuse to form a zygote. Common mistake: mixing up asexual fission methods with sexual conjugation in algae.

A student might incorrectly select small dull petals or light powdery pollen, but a tubular shape is the correct feature because it accommodates a bird's beak for nectar feeding. Common mistake: confusing bird pollination traits with insect or wind pollination characteristics.

An examinee might mistakenly choose karyokinesis or mitosis which refer to nuclear events, but cytokinesis is correct because it specifically divides the cytoplasm after nuclear division so each daughter cell gets organelles. Common mistake: confusing nuclear division with cytoplasmic division.

A student might incorrectly pick high clay content or high water content, but a loose texture is correct because it lets roots penetrate easily, supporting overall growth and nutrient absorption. Common mistake: assuming compact soils provide better structural support for root systems.