JAMB UTME - Biology - 2018

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An animal that is active during the day is known as a diurnal animal. This means that it is awake and active during the daytime hours, when the sun is shining, and typically sleeps or rests during the night. Diurnal animals have evolved to take advantage of the sunlight and are often adapted to see well in bright light. Examples of diurnal animals include humans, birds, squirrels, and many species of primates.

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The correct answer is "species". Species are a group of living organisms that share common characteristics and can interbreed to produce fertile offspring. This means that members of the same species can mate and produce offspring that can themselves reproduce, while organisms from different species cannot produce fertile offspring together. For example, dogs can breed with other dogs to produce fertile puppies, but they cannot breed with cats to produce offspring that can reproduce. Therefore, dogs and cats belong to different species.

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The rate, or velocity, of blood flow varies inversely with the total cross-sectional area of the blood vessels. As the total cross-sectional area of the vessels increases, the velocity of flow decreases. Blood flow is slowest in the capillaries, which allows time for exchange of gases and nutrients. Flow is slowest in the capillaries because of their larger cross-sectional area and narrow diameter.

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The flippers of a whale and the fins of a fish are examples of convergent evolution. Convergent evolution is a process where species that are not closely related, but live in similar environments, evolve similar structures or adaptations to solve similar problems. This is also known as "parallel evolution". For example, whales and fish both live in water, and both need to be able to swim and maneuver. Over time, both species have evolved flippers or fins as a solution to these challenges, even though whales are mammals and fish are fish. This convergence of similar structures in unrelated species is a result of convergent evolution.

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The vitamin that is important in the formation of the retina pigment is Vitamin A. The retina is a part of the eye that contains cells called rods and cones which help us to see. Vitamin A is important for the normal functioning of these cells, especially the rods, which are responsible for vision in low light conditions. The retina pigment, also known as rhodopsin, is a protein found in the rods of the retina. It helps to absorb light and convert it into electrical signals that the brain can interpret as vision. Vitamin A plays a crucial role in the formation of this pigment, and a deficiency of this vitamin can lead to a condition called night blindness, where a person has difficulty seeing in low light conditions. In summary, Vitamin A is essential for the normal functioning of the cells in the retina, especially the rods, and is important for the formation of the retina pigment, which is necessary for vision in low light conditions.

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Ozone sits in the upper atmosphere and absorbs ultraviolet radiaton, another type of solar energy that's harmful to humans, animals and plants. CFCs and halons cause chemical reactions that break down ozone molecules, reducing ozone's ultraviolet radiation-absorbing capacity. Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.

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The accessory materials found in a chicken egg include the albumen (the egg white), the shell membrane (the thin membrane that lines the inside of the eggshell), and the shell itself. The germinal disc, on the other hand, is not an accessory material, but rather an important part of the egg. The germinal disc, also known as the blastoderm, is a small, round spot on the surface of the yolk that contains the genetic material necessary for the development of the embryo. It is located on the surface of the yolk and can be seen as a small white spot when you crack open an egg. This is where the sperm enters and fertilizes the egg, leading to the development of the embryo. So to summarize, the accessory materials found in a chicken egg are the albumen, shell membrane, and shell, while the germinal disc is an essential part of the egg that is responsible for the development of the embryo.

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The total salt content in blood is about 0.85 to 0.9%. Salt, which is also known as sodium chloride, is an essential mineral that is necessary for many bodily functions such as maintaining fluid balance, transmitting nerve impulses, and contracting muscles. However, too much salt in the blood can lead to health problems like high blood pressure, so it's important to maintain a proper balance. The normal range for salt content in the blood is typically around 0.9%, which is equivalent to 9 grams of salt per liter of blood.

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Special temporary organs or embryonic membranes form within the egg, both to protect the embryo and to provide for its nutrition, respiration, and excretion. These organs include the yolk sac. The yolk sac is also responsible for the initial circulation and is in charge of delivering nutrients, via a primitive aorta, to the developing embryo through a process called vitelline circulation.

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The pollutant that is mostly associated with acid rain is nitrogen (IV) oxide, also known as nitrogen dioxide (NO2). NO2 is produced when fuels such as coal, oil, and gas are burned at high temperatures, particularly in vehicles and power plants. It is a gas that can react with other chemicals in the atmosphere to form nitric acid (HNO3), which can then fall to the ground as acid rain. When acid rain falls on soil, it can lower the pH and make it more acidic. This can have negative effects on plants and animals that live in the soil, as well as on the quality of the water in lakes and streams. In addition, acid rain can corrode buildings and other structures made of stone, metal, or concrete. To reduce the production of nitrogen (IV) oxide and the formation of acid rain, it is important to reduce the use of fossil fuels and to use cleaner sources of energy, such as wind, solar, and hydropower. Additionally, regulations and policies can be put in place to limit the emissions of nitrogen (IV) oxide from vehicles and power plants.

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Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides.

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Etiolation is caused by the influence of LIGHT. Etiolation refers to the physical changes that occur in a plant when it is grown in the absence of sufficient light. When a plant does not receive enough light, it elongates its stem and leaves to reach for the light source. This results in a spindly, pale appearance, as the plant allocates its resources towards vertical growth rather than producing chlorophyll and other pigments needed for photosynthesis. Therefore, the absence of light, or insufficient light, is the primary cause of etiolation. While mineral salts, water, and carbon dioxide are all necessary for plant growth, they do not directly cause etiolation.

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Trichocyst, a structure in the cortex of certain ciliate and flagellate protozoans consisting of a cavity and long, thin threads that can be ejected in response to certain stimuli. Trichocysts may be widely distributed over an organism or restricted to certain areas (e.g., tentacles, papillae, around the mouth). It is also a structure in the cortex of certain ciliate and flagellate protozoans consisting of a cavity and long, thin threads that can be ejected in response to certain stimuli.

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Double fertilization is a unique feature of angiosperms, also known as flowering plants. During double fertilization, two sperm cells from the pollen grain fertilize two different cells in the female reproductive structure of the flower. One sperm cell fertilizes the egg cell to form the zygote, which will develop into the embryo of the seed. The other sperm cell fertilizes two nuclei in the central cell, which results in the formation of a triploid cell called the endosperm. The endosperm provides nourishment to the developing embryo. This process is unique to angiosperms and is not seen in bryophytes, pteridophytes, or algae. It is one of the key factors that has contributed to the success of angiosperms, as the endosperm provides a rich source of nutrients for the developing embryo, giving it a competitive advantage for survival and growth.

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The giraffe's long neck is a perfect adaptation to the animal's natural habitat. Clearly the giraffe evolved this uncommon and helpful trait in order to reach those nourishing leaves. That's how natural selection works. Use and disuse' theory in human life advocate the idea that animals acquired characteristics after using certain physical traits constantly.

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Maltose is a disaccharide, which means it is made up of two simple sugar molecules. Specifically, maltose is made up of two glucose molecules that are joined together by a type of bond called a glycosidic bond. Glucose is a monosaccharide, which means it is a simple sugar that cannot be broken down into any simpler sugars. Maltose is formed when two glucose molecules are linked together by a glycosidic bond. This bond is formed by the removal of a molecule of water between the two glucose molecules. The resulting molecule of maltose is therefore a combination of two glucose molecules. Sucrose, on the other hand, is a different type of disaccharide that is made up of one glucose molecule and one fructose molecule, while galactose is a monosaccharide that can combine with glucose to form lactose, a disaccharide found in milk. So to summarize, maltose is a disaccharide made up of two glucose molecules that are linked together by a glycosidic bond. It is not made up of fructose, sucrose, or galactose.

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The temporary union of two organisms and the exchange of micronuclear elements is called "conjugation". Conjugation is a process of sexual reproduction in some single-celled organisms, such as certain bacteria and protozoa. During conjugation, two organisms come together and form a temporary union. They exchange genetic material through a small opening that forms between them, allowing the exchange of micronuclear elements, such as DNA. The exchanged micronuclear elements contain genetic information that can be used to produce new offspring with different genetic traits from the parent organisms. This allows for increased genetic diversity within a population, which can be important for adaptation and evolution. In summary, conjugation is a process of temporary union and genetic exchange between two organisms, which can lead to increased genetic diversity within a population.

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Scabies is the disease that is not hereditary. Scabies is a skin infestation caused by a tiny mite called Sarcoptes scabiei. It spreads through direct skin-to-skin contact with an infected person. Scabies is not a genetic disorder and does not pass down from parent to child through genes. It is caused by a microscopic organism that can infect anyone who comes into contact with it. On the other hand, Albinism, Haemophilia, and Color blindness are all hereditary diseases. Albinism is a genetic condition that affects the production of melanin, resulting in little or no pigment in the skin, hair, and eyes. Haemophilia is a genetic disorder that affects the blood's ability to clot properly. Color blindness is a genetic condition that affects the ability to distinguish between different colors. In summary, while Scabies is caused by a tiny mite and is not hereditary, Albinism, Haemophilia, and Color blindness are all genetic conditions that are inherited from one's parents.

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The gland that is present close to the trachea is the thyroid gland. The thyroid gland is a small, butterfly-shaped gland located in the neck, just below the Adam's apple and above the collarbone. It wraps around the front of the trachea, which is the tube that carries air to the lungs. The thyroid gland produces hormones that regulate many important functions in the body, including metabolism, growth, and development. When the thyroid gland is not working properly, it can cause a variety of health problems, including weight gain or loss, fatigue, and mood changes.

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The role of the membrane in plant cells is played by the cell wall. The cell wall is a protective outer layer that surrounds the plasma membrane, which is a thin layer that encloses the cytoplasm and other cell structures. The cell wall provides support and structure to the cell, and also helps to maintain the shape of the cell. The nucleolus is a structure within the nucleus of a cell that is involved in the production of ribosomes, while the cytoplasm is the gel-like substance that fills the interior of a cell and contains all of the cell's organelles. The mitochondrion is an organelle within the cytoplasm that is responsible for generating energy for the cell.

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The energy released by 1 gram of glucose is about 4 kcal. To put it simply, when our bodies break down glucose, a type of sugar that is a source of energy, it releases energy that we can use. This energy is measured in units of calories, and 1 kilocalorie (kcal) is equivalent to 1,000 calories. So, when 1 gram of glucose is broken down, it releases approximately 4 kcal of energy.

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The process that removes carbon from the atmosphere is "photosynthesis". Photosynthesis is the process by which green plants and other organisms use sunlight to synthesize foods with the help of carbon dioxide and water. During photosynthesis, carbon dioxide (CO2) is taken in from the atmosphere and used to produce glucose, a type of sugar that serves as food for the plant. In this process, the carbon from CO2 is converted into organic carbon compounds, which are then used to build the plant's structure and stored in the plant's tissues. This means that photosynthesis helps to remove carbon from the atmosphere and store it in the biomass of plants. In contrast, processes such as putrefaction, volcanic eruption, and burning of fuels release carbon into the atmosphere, contributing to the increase of atmospheric carbon dioxide levels and, in turn, to climate change.

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Cnidaria is a phylum under Kingdom Animalia containing over 11,000 species of animals found exclusively in aquatic environments: they are predominantly marine. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Modern cnidarians are generally classified into four main classes: sessile Anthozoa (sea anemones, corals, sea pens); swimming Scyphozoa (jellyfish) and Cubozoa (box jellies); and Hydrozoa, a diverse group that includes all the freshwater cnidarians as well as many marine forms, and has both sessile members such as Hydra and colonial swimmers such as the Portuguese Man o' War. The Turbellaria are one of the traditional sub-divisions of the phylum Platyhelminthes, and include all the sub-groups that are not exclusively parasitic.

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Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.

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Spectacles with convex lenses correct long-sightedness by converging the light rays before they enter the eye. In long-sightedness, also known as hyperopia, the eyeball is too short, which causes light to focus behind the retina instead of directly on it. This results in blurry vision, especially when looking at close objects. Convex lenses are thicker in the middle and thinner at the edges, and they bend light rays towards each other. When a person with long-sightedness wears spectacles with convex lenses, the lenses converge the light rays before they enter the eye, which compensates for the shortness of the eyeball. This causes the light rays to focus directly on the retina, which results in clearer vision. Therefore, by converging the light rays before they enter the eye, convex lenses correct long-sightedness.

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The production of pancreatic hormones, including insulin, somatostatin, gastrin, and glucagon, play an important role in maintaining sugar and salt balance in our bodies.

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A mammary gland is an exocrine gland in mammals that produces milk to feed young offspring. Mammals get their name from the Latin word mamma, "breast". Hens do not have mammary glands.

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An example of a radially symmetrical organism is Hydra. Radial symmetry means that an organism has a circular shape and its body parts are arranged around a central axis, like the spokes on a wheel. Hydra is a small, freshwater animal that has a cylindrical body and tentacles that radiate out from its central axis. This type of symmetry allows Hydra to detect and capture prey from all directions. Planaria are also radially symmetrical flatworms, while tapeworms and roundworms are examples of organisms with bilateral symmetry, meaning that they have a distinct front and back and a left and right side.

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While humans and many other species have red blood, due to the iron in their hemoglobin, other animals have different colored blood. Spiders (as well as horseshoe crabs and certain other arthropods) have blue blood due to the presence of copper-based hemocyanin in their blood. Some animals, such as the sea cucumbers, even have yellow blood. What could make blood yellow? The yellow coloration is due to a high concentration of the yellow vanadium-based pigment, vanabin. Unlike hemoglobin and hemocyanin, vanabin does not seem to be involved in oxygen transport.

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Saline, also known as saline solution, is a mixture of sodium chloride in water and has a number of uses in medicine. Intravenous therapy (IV) is a therapy that delivers liquid substances directly into a vein. Saline is used in I.V. therapy, intravenously supplying extra water to rehydrate patients or supplying the daily water and salt needs ("maintenance" needs) of a patient who is unable to take them by mouth. Because infusing a solution of low osmolality can cause problems such as hemolysis, intravenous solutions with reduced saline concentrations typically have dextrose (glucose) added to maintain a safe osmolality while providing less sodium chloride. The amount of normal saline infused depends largely on the needs of the patient (e.g. ongoing diarrhea or heart failure).

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The vessel carrying oxygenated blood to the tissues is called an artery. Arteries are blood vessels that carry blood away from the heart, and they have thick, muscular walls that can withstand the high pressure of blood being pumped by the heart. The oxygenated blood that is pumped out of the left ventricle of the heart into the aorta is then distributed throughout the body via the network of arteries. Arteries branch into smaller vessels called arterioles and then into even smaller vessels called capillaries, where oxygen and nutrients are delivered to the body's tissues. So, arteries play a crucial role in ensuring that oxygenated blood is delivered to the body's tissues to support their proper functioning.

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Like red cells, platelets (thrombocytes) have no nucleus. However, unlike red cells that originate in the marrow as nucleated cells and lose their nucleus, platelets are produced by budding off from a giant multinucleated marrow cell called a megakaryocyte.

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The cycle that involves the process of precipitation and transpiration is the water cycle. The water cycle is the process by which water circulates through the Earth's environment. It starts with the evaporation of water from bodies of water, such as oceans, lakes, and rivers, as well as from the soil and plants through a process called transpiration. This water vapor then rises into the atmosphere, where it cools and condenses into clouds. When these clouds become heavy enough, the water falls back to Earth as precipitation, which can take the form of rain, snow, sleet, or hail. Once the precipitation falls to the ground, it can either be absorbed by the soil and become groundwater or run off into bodies of water. From there, the cycle starts again. In summary, the water cycle involves the process of precipitation, which is the falling of water from the atmosphere to the Earth's surface, as well as the process of transpiration, which is the release of water vapor from plants. This cycle is essential for providing fresh water to living things and maintaining the Earth's environment.

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The organism designated P in the food chain is normally sustained by energy from the sun. This is because P is likely at the bottom of the food chain, which means it is a primary producer. Primary producers, such as green plants, use energy from the sun to produce their own food through photosynthesis. This food is then consumed by the next organism in the food chain, which is Q. The energy then passes from one organism to the next, all the way up the food chain to the top predator. Therefore, in this food chain, P is likely a green plant or another type of primary producer that uses energy from the sun to produce its own food, making sunlight the source of energy for P.

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Cold-blooded animals are referred to as "poikilothermic". Poikilothermic animals are also known as "ectothermic" animals, which means that their body temperature is regulated by the environment around them. This is in contrast to "homoeothermic" animals, also known as "endothermic" animals, which can regulate their own body temperature internally. Examples of poikilothermic animals include reptiles, amphibians, and most fish. These animals are often seen basking in the sun to warm up or seeking out cooler places in order to lower their body temperature. They are able to function at a range of different temperatures, but their bodily functions are often slower at cooler temperatures. On the other hand, homoeothermic animals, such as mammals and birds, are able to maintain a stable internal body temperature, even when the temperature of their environment fluctuates. This allows them to function effectively in a wider range of environmental conditions.

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Saprophytism is the ability of certain plants to live in dead or decaying organic matter. A saprophyte or saprotroph is an organism which gets its energy from dead and decaying organic matter. This may be decaying pieces of plants or animals. This means that saprophytes are heterotrophs. They are consumers in the food chain.

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Holozoic nutrition is a type of heterotrophic nutrition that is characterized by the internalization (ingestion) and internal processing of gaseous, liquid or solid food particles. Protozoa, such as amoebas, and most of the free living animals,such as animals, exhibit this type of nutrition.
In holozoic nutrition the energy and organic building blocks are obtained by ingesting and then digesting other organisms or pieces of other organisms, including blood and decaying organic matter. This contrasts with holophytic nutrition, in which energy and organic building blocks are obtained through photosynthesis or chemosynthesis, and with saprozoic nutrition, in which digestive enzymes are released externally and the resulting monomers (small organic molecules) are absorbed directly from the environment.
Holophytic (plant-like), holozoic (animal- like), and saprophytic nutrition is found in Euglena. Euglena obtains its carbohydrate food by photosynthesis and nitrogenous food by absorption from the surroundings. Its holozoic nutrition is, however, doubtful.

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The vitamin that is commonly associated with swollen, bleeding gums is Vitamin C. Vitamin C is an essential nutrient that helps in the formation of collagen, which is an important component of connective tissues like gums. Without enough Vitamin C, the collagen fibers in gums can weaken and break down, leading to inflammation, bleeding, and even tooth loss. In addition, Vitamin C has antioxidant properties that can help to protect the gums from damage caused by harmful free radicals. Therefore, a diet deficient in Vitamin C can cause gums to become swollen, inflamed, and bleed easily. Consuming sufficient amounts of Vitamin C can help to prevent and treat these symptoms, which is why it is important to include Vitamin C-rich foods in your diet, such as citrus fruits, berries, kiwi, broccoli, and peppers, among others.