Diatoms are a type of phytoplankton and primary producers that form the base of the marine food chain, supporting various marine life

This sequence accurately represents a food chain where spirogyra (a type of algae) is consumed by tadpoles, which are then eaten by fish, followed by kingfishers and sealions.

The light organs in deep-sea fish are often used to attract prey in the dark ocean depths, aiding in their hunting strategy.

This appears to be a mistake in the options. The largest source of marine food for humans typically comes from various marine environments, but the correct answer in context is unclear. "Freshwater" is not normally the largest source of marine food.

Fish and other marine organisms often have adaptations like air bladders that help them maintain buoyancy in the water.

Tropical rainforests are characterized by high temperatures and high humidity. The statement is incorrect because low humidity does not describe tropical rainforests accurately.

Algae are a type of phytoplankton that perform photosynthesis, making them primary producers in aquatic ecosystems.

The description of a dark forest floor, a tall canopy, and abundant arboreal animals strongly indicates a tropical rainforest habitat.

This is the correct sequence in the marine food chain, where phytoplankton serve as primary producers, followed by zooplankton as primary consumers, and so forth.

Kano is primarily in a drier region and does not have tropical rainforest habitat. Akwa Ibom, Anambra, and Oyo have significant rainforest areas

Plankton often have adaptations like oil globules or gas-filled sacs that help them remain buoyant in the water column

Nekton refers to larger marine organisms that can swim freely and actively against currents, such as fish and whales.

Muddy shores are often rich in nutrients and invertebrates, attracting more birds that feed on these organisms. Sandy shores may also attract birds, but muddy shores typically have higher bird diversity

Many aquatic animals produce mucus or slime to help them cling to surfaces and avoid being swept away by currents.

Rocky shores are often rich in biodiversity because they provide numerous habitats and niches for various marine organisms. They support a variety of species compared to sandy shores.

Many benthic organisms are adapted to cold, deep-sea environments, where temperatures are low. They do not typically require warm habitats.

Plankton refers to organisms that drift in the water column and cannot swim against currents. They include both phytoplankton (producers) and zooplankton (consumers).

Arid land is characterized by dry conditions and does not represent an estuarine habitat, which is defined by the mixing of fresh and saltwater

In estuarine habitats, the food chain starts with organic detritus, which is consumed by worms (detritivores), followed by fish and then birds.

Cyclops (cyclopoid copepods) are zooplankton, not phytoplankton. The other options (diatom, spyrogyra, chlamydomonas) are types of phytoplankton.

Arboreal animals are typically smaller and more agile to navigate the trees. A large body build would be a disadvantage for climbing and moving through branches.

Peat is the accumulative organic material found in wetlands, formed from decayed plant matter in anaerobic (low oxygen) conditions.

Streams are typically flowing bodies of water, not stagnant. The other statements accurately describe characteristics of freshwater ecosystems.

Protozoa are microscopic animals that are classified as zooplankton. The other options are primarily photosynthetic organisms.

Algae are classified as plankton, not nekton, as they do not swim actively but instead drift with currents

Estuarine habitats are characterized by the mixing of freshwater and saltwater, making them aquatic environments. In contrast, arid land, marshes, and swamps are all terrestrial habitats.

Temperature and rainfall are the key climatic factors that determine the types of vegetation that can thrive in terrestrial habitats.

The forest floor of tropical rainforests is often dark and has limited sunlight, resulting in a thin undergrowth. Therefore, this statement is incorrect.

The subzones of the littoral (or intertidal) zone typically include the intertidal, splash zone, and tidal zone. "Transtidal" is not commonly recognized as a specific subzone.

Light organs can serve multiple purposes, including attracting mates and prey, helping deep-sea fish communicate and feed in their dark environment.

While some organisms may reproduce under stress conditions, the primary survival strategies include laying heat-resistant eggs or burrowing, rather than increasing procreation.

Zonation refers to the spatial arrangement of different organisms in an ecosystem based on their tolerance to environmental factors such as light, temperature, and salinity.

Sandy shores typically have less marine biodiversity compared to rocky shores, which provide more habitat complexity. Sandy substrates can be less stable and provide fewer niches for marine organisms

Epiphytes are plants that grow on other plants, typically trees, without harming them. They are considered arboreal because they live in the canopy of forests, using the trees for support.

The benthic zone refers to the lowest ecological zone in a body of water, typically the ocean floor, and does not start at the surface. It extends from the intertidal zone down to the deepest parts of the ocean. The statement about it being from the surface to 500 meters is incorrect.

The emergent layer is actually above the canopy layer, consisting of the tallest trees that rise above the main canopy. The other descriptions are accurate for the rainforest structure.

Salinity in brackish water is primarily influenced by factors such as rainfall (wet/dry seasons) and ocean tides, rather than water depth.

While the benthic zone can support life, it is often less favorable due to high pressure, low light, and sometimes low oxygen levels, especially in deeper areas.

Tidal waves primarily affect marine environments rather than freshwater habitats. The other factors (oxygen concentration, temperature, turbidity) significantly influence zonation in freshwater ecosystems.

Lagos is located in a region of Nigeria that features tropical rainforest. Other regions like Kaduna and Bauchi are more arid or savanna.

While many trees in tropical rainforests have smooth bark to prevent water loss and support growth, fissured bark is not a common characteristic. The other options (tall stems, branches near the top, presence of epiphytes) are typical of tropical rainforest trees.

Marshes and swamps typically have murky water due to high organic content and decomposition, not clean and clear water.

The subtidal zone, located just below the intertidal zone, is rich in both producers (like algae) and consumers (like fish), supporting diverse marine life.

Brackish water is a mixture of freshwater and seawater, typically found in estuaries. The other options do not specifically describe this mixture.

Guinea fowl are ground-dwelling birds and are not adapted for life in the trees. The other options (flying squirrel, flying lizard, chameleon) are all capable of living in trees.

Generally, ground-dwelling animals in tropical rainforests may be larger than arboreal animals, which are often smaller and adapted for climbing. This statement is misleading.

Estuarine areas are where freshwater from rivers meets ocean water, leading to tidal flows. The other options refer to zones or areas that do not specifically denote where tides enter.

Camels are adapted to arid desert environments and are not found in tropical rainforests. The other animals listed (elephants, monkeys, antelopes) are commonly found in such habitats.

Floating is not an adaptation for terrestrial environments; it is more relevant to aquatic habitats. The other options describe adaptations for survival on land.

Variation refers to genetic diversity within a population and does not directly affect population size like disease, immigration, or abiotic factors do.

Desert plants are generally not epiphytes, which grow on other plants; they are adapted to survive in arid conditions

Disease can significantly affect population density by increasing mortality rates, unlike factors like flood or drought, which can cause temporary changes.

Oxides of nitrogen also contribute to acid rain, reacting with water to form nitric acid.

This sequence represents a correct food chain, starting from a primary producer (grass) to primary consumers (grasshoppers), and then moving up to secondary consumers (toads), tertiary consumers (snakes), and finally quaternary consumers (hawks).

A long neck is not a typical adaptation for aquatic life. Adaptations like gills, streamlined bodies, and a development of tails are common in aquatic organisms.

Tapeworms do not have a circulatory system; they rely on diffusion for nutrient and gas exchange. They also lack an alimentary system

Tapeworms do not have a respiratory system; they exchange gases through their body surface

The contractile vacuole functions to expel excess water that accumulates in the cell, maintaining osmotic balance.

Xerophytes are adapted to survive in arid environments with scarce water, not areas with plenty of water.

Mesophytes, which thrive in environments with moderate water availability, typically have well-developed roots to access moisture.

Stomata are primarily for gas exchange, allowing for the uptake of carbon dioxide and the release of oxygen, not for absorbing oxygen directly.

The ability to moult is a general adaptation seen in many organisms for growth and development, not specifically a parasitic adaptation. The other options directly relate to adaptations that help parasites survive in their hosts.

Noise pollution can lead to various health issues such as poor sleep, headaches, and high blood pressure, but it does not cause blindness.

Tapeworms lack a mouth and digestive tract; they absorb nutrients directly through their skin.

Succulents are specialized plant structures that store water, allowing plants to survive in dry conditions.

Proglottids do not have a digestive system; they absorb nutrients through their body surface.

This statement is incorrect; rhizobia form a mutualistic relationship with leguminous plants, fixing nitrogen and providing benefits rather than causing harm.

Countershading is a form of camouflage that helps animals avoid predation, but it does not directly influence population size. In contrast, food availability, disease, and water supply are critical factors that can significantly impact population dynamics.

Nephridia are excretory organs found in some invertebrates, not specifically adaptations for parasitism. The other options (haustorium, hook) are adaptations that assist in attachment and nutrient absorption

Filarial worms are transmitted by mosquito bites, causing diseases like lymphatic filariasis, whereas the other worms listed do not have mosquito vectors.

Birds that feed on grains typically have stout, short beaks suitable for cracking seeds, not long wide beaks.

While killing pests with pesticides can control pests, it can also lead to soil pollution due to chemical residues. Preventing overgrazing and deforestation, as well as crop rotation, are effective strategies for preventing soil pollution.

Epiphytes live on other plants but do not harm them, unlike parasites, which take nutrients from the host.

Hydrophytes often have less developed conducting systems compared to terrestrial plants because they live in water, where water is readily available.

Dredging is used to remove sediment and debris from the bottom of water bodies, but it is not effective for clearing crude oil. The other methods (using adsorbents, growing oil-eating bacteria, and using chemical dispersants) are specifically designed to address oil pollution.

Large aquatic animals typically have buoyancy support from water, reducing the need for a robust skeletal structure compared to terrestrial animals, which require strong support systems against gravity.

Fallouts refer to the radioactive particles that fall to the ground after a nuclear explosion, posing serious health risks.

Goats are herbivores that graze on plants, and they have a predictable food source. In contrast, hyenas, snakes, and hawks rely on hunting, which involves uncertainty in finding prey.

Commensalism is actually a relationship where one party benefits while the other is neither

Tapeworms do not have hooks for digging; they have hooks or suckers for attachment to the host's intestinal wall.

Fishing itself does not directly cause water pollution. In contrast, crude oil drilling, dredging, and agricultural waste are activities that can lead to water contamination.

Sulphur dioxide is a primary contributor to acid rain, as it reacts with water in the atmosphere to form sulfuric acid.

Proper waste disposal is a general practice for managing waste, but it is not specifically a method for preventing soil pollution compared to crop rotation, manuring, and preventing overgrazing.

The relationship between flatworms and the human intestine is parasitic. In contrast, rhizobium and leguminous plants, epiphytes and tall trees, and cattle and cattle egrets all demonstrate mutualism, where both parties benefit.

While nuclear waste can contaminate water, it is not as common as agricultural waste, household wastes, or industrial waste, which frequently contribute to water pollution.

While some nematodes are hermaphroditic, many have separate sexes. The other statements are generally true for nematodes.

The use of pesticides contributes to soil pollution through chemical residues that can harm soil health. Dredging and dumping of garbage can also cause pollution, but planting trees helps improve soil quality.

Xerophytes typically have narrow or reduced leaves to minimize water loss, not broad leaves.

Rickets is primarily caused by a deficiency of vitamin D, calcium, or phosphate, not by tapeworm infection. The other conditions (anemia, malnutrition, indigestion) can be related to parasitic infections.

Smog typically occurs in large, industrialized cities due to high levels of pollution, not primarily in small or undeveloped areas.

River blindness (onchocerciasis) is caused by the filarial worm transmitted by blackflies.

The ozone layer protects the Earth by absorbing the majority of the sun's harmful ultraviolet (UV) radiation, preventing excessive irradiation.

Nematodes have a complete digestive system and do not rely on diffusion for feeding. They actively ingest food.

Tapeworms are typically parasitic and cause harm to their hosts rather than providing mutual benefits, which is what symbiosis implies

Color adaptation often serves to camouflage organisms, helping them avoid predation.

An increase in natality (birth rate) typically occurs when resources are plentiful, not during food shortages. Food shortages can lead to competition, cannibalism, and migration, but not to increased birth rates.

This refers to a food chain, not an adaptation of the tapeworm itself. Tapeworms exploit hosts for nutrients rather than utilizing the food chain.

Noise pollution primarily affects health and well-being, leading to issues like deafness, restlessness, and headaches, but it does not directly cause malnutrition.

The act of dumping sewage and garbage on land results in land pollution, which negatively impacts soil and the surrounding environment.

While the cerebrum contributes to many cognitive functions, the perception of smell is primarily handled by the olfactory bulb and lobe, not the cerebrum itself

The axon is a long projection that carries impulses away from the cell body to other neurons or muscles.

The nervous system consists of the brain, spinal cord, and nerves, which facilitate communication throughout the body. Muscles, while they respond to signals from the nervous system, are part of the muscular system, not the nervous system.

In a resting neuron, there is a higher concentration of sodium ions outside the cell and a higher concentration of potassium ions inside the cell. This distribution is crucial for establishing the resting membrane potential and preparing the neuron for action potential generation.

The dura mater is the tough, outermost layer of the meninges. It provides the first line of defense against physical impacts and infections

The olfactory lobe is primarily responsible for processing smells. It receives sensory input from the olfactory receptors in the nasal cavity and is crucial for the sense of smell.

The brain coordinates all nervous activities, including motor control, sensory processing, and cognitive functions. During a race, it processes information from the environment, regulates heart rate, and directs muscle movements, making it the central hub for coordination

A reflex arc follows this pathway: a stimulus activates a receptor, which sends a signal through a sensory neuron to the spinal cord. There, an intermediate (or interneuron) processes the signal and relays it to a motor neuron, which then activates an effector muscle to produce a response

The sympathetic nervous system inhibits peristalsis (the movement of the intestines) to divert energy to muscles, increasing heart rate and respiration instead.

The peripheral nervous system (PNS) is divided into the somatic nervous system, which controls voluntary movements, and the autonomic nervous system, which regulates involuntary functions

The hypothalamus is involved in regulating many autonomic functions such as hunger, temperature control, and emotional responses, but it does not directly perceive pain. Pain perception is primarily processed in the thalamus and cerebral cortex

The hypothalamus does not play a direct role in the perception of smell; this function is primarily associated with the olfactory system. The hypothalamus is involved in hormonal regulation, body water balance, and emotional responses

Motor neurons transmit signals from the brain and spinal cord to muscles, facilitating movement.

The medulla oblongata is the lowest part of the brainstem and connects directly to the spinal cord, playing a crucial role in autonomic control.

The autonomic nervous system manages involuntary functions, including heart rate, digestion, and respiratory rate, maintaining homeostasis in the body

Nerves are the structures that transmit electrical impulses throughout the body, facilitating communication between the brain, spinal cord, and other body parts

There are 12 pairs of cranial nerves that emerge directly from the brain and brainstem, responsible for various functions including sensory and motor activities.

The brain is considered the most specialized organ due to its complex functions, including cognition, memory, emotional regulation, and coordination of bodily functions. It is uniquely structured to process vast amounts of information and control the body

Cerebrospinal fluid (CSF) circulates in the space between the pia mater and arachnoid mater, providing cushioning for the brain, removing waste, and delivering nutrients

This statement is incorrect because the sympathetic nervous system actually increases heart rate and cardiac output in response to stress or danger.

The transmission of nerve impulses relies on the movement of sodium (Na+) and potassium (K+) ions across the neuron's membrane. This movement generates action potentials, which are essential for impulse transmission.