JAMB UTME - Biology - 2018

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The group of organisms that have kidneys as the excretory organ is: fishes, amphibians, birds, and man. Kidneys are specialized organs that remove waste products, excess water, and other impurities from the blood. These waste products are then eliminated from the body as urine. Fishes, amphibians, birds, and mammals (including humans) all have kidneys as their primary excretory organ. In fish, the kidneys are responsible for removing excess water and electrolytes from the blood. In amphibians, the kidneys also play a role in maintaining water balance, as well as removing nitrogenous wastes. In birds and mammals, the kidneys are responsible for filtering the blood, regulating water and electrolyte balance, and eliminating waste products. In contrast, annelids (a group of segmented worms), insects, protozoans, reptiles, and tapeworms have different excretory organs. For example, insects have specialized structures called Malpighian tubules that remove waste products and excess water from their blood, while tapeworms excrete waste products through their skin.

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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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The instrument used to estimate the number of plants in a habitat is a quadrant. A quadrant is a square or rectangular frame that is used to isolate a specific area within a habitat for study. It is typically made of a lightweight and durable material, such as metal or plastic, and can be any size, depending on the needs of the study. To estimate the number of plants in a habitat using a quadrant, researchers randomly select several quadrants within the study area and place them on the ground. They then count the number of plants within the quadrant and use this information to estimate the number of plants in the entire study area. Quadrants are a commonly used tool in ecology and are particularly useful for estimating the density and distribution of plant populations. They are simple to use and can provide valuable information for researchers who are interested in understanding the dynamics of plant communities.

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Note: Evolution is a process of gradual change that takes place over many generations, during which species of animals, plants, or insects slowly change some of their physical characteristics.

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The part of the ear which contains nerve cells sensitive to sound vibrations is the cochlea. The cochlea is a small, spiral-shaped structure in the inner ear. It is responsible for translating sound waves into electrical signals that can be interpreted by the brain. The cochlea contains tiny hair cells that are responsible for detecting sound vibrations. These hair cells are arranged along the length of the cochlea and are stimulated by different frequencies of sound. When sound waves enter the ear, they cause the eardrum to vibrate. These vibrations are then transmitted to the three small bones in the middle ear, including the malleus. The malleus transmits the vibrations to the inner ear, where they are picked up by the hair cells in the cochlea. The hair cells then convert the vibrations into electrical signals that are transmitted to the brain via the auditory nerve, allowing us to hear and interpret sounds. In summary, the cochlea is the part of the ear that contains nerve cells sensitive to sound vibrations. The hair cells within the cochlea are responsible for detecting sound waves and translating them into electrical signals that can be interpreted by the brain.

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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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An adult tapeworm consists of a knoblike head, or scolex, equipped with hooks for attaching to the intestinal wall of the host (which may be a human), a neck region, and a series of flat, rectangular body segments, or proglottids, generated by the neck. Scolex is used for attachment to the intestinal wall.

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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 plant tissue that carries water and mineral salts from the roots to other parts of the plant is called xylem. Xylem is like a pipeline that runs throughout the plant and is responsible for transporting water and dissolved nutrients from the roots to the leaves and other parts of the plant. This tissue is made up of specialized cells called tracheids and vessel elements that are arranged end to end to form long, hollow tubes. These tubes allow water to flow through them with minimal resistance, and the water is pulled up through the xylem by a process called transpiration. In summary, xylem is the tissue responsible for carrying water and mineral salts from the roots to the rest of the plant, and it does so through a network of specialized cells that form long, hollow tubes.

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Primary consumers eat these plants exclusively and are all herbivores. We defined secondary consumers as organisms, primarily animals, which eat primary consumers. Furthermore, secondary consumers can be classified into one of two groups: carnivores, or meat eaters, and omnivores, which are plant and meat eaters.

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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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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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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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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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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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Sandy soils are well drained. They have low water holding capacity and are therefore drought prone. They become firm when wet (the opposite of clay), and loose when dry. Sandy soil is light and easy to dig.

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The arteries are the blood vessels that deliver oxygen-rich blood from the heart to the tissues of the body. Each artery is a muscular tube lined by smooth tissue and has three layers: The intima, the inner layer lined by a smooth tissue called endothelium. Arteries have smaller lumens than veins, a characteristic that helps to maintain the pressure of blood moving through the system. They carry blood away from the heart. Pulmonary arteries transport blood that has a low oxygen content from the right ventricle to the lungs. Arteries do not possess valves at intervals throughout their length

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One distinguishing feature of mammals is the possession of hair. Hair is a unique type of structure that grows from the skin of mammals and is made up of a protein called keratin. Hair serves many important functions in mammals, such as keeping the body warm, protecting the skin from damage, and providing sensory information. Hair can also be used for social communication, such as when a cat raises its fur to make itself look bigger and more intimidating. While other animals like reptiles may have scales, and birds may have feathers, only mammals have hair as a defining feature.

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The curvature movement of plants in response to the stimulus of water is called "hydrotropism." Hydrotropism is a type of plant movement that occurs when a plant's roots grow towards a source of water. This is an important mechanism that allows plants to find water and nutrients in the soil. When a plant is exposed to a source of water, such as a moist patch of soil, the plant's roots will start to grow towards the water. This is because the cells on the side of the root closest to the water absorb more water and expand, causing the root to bend towards the source of water. As the root grows towards the water, it will continue to bend until it reaches the water source. Hydrotropism is different from other types of plant movements, such as geotropism, phototropism, and thigmotropism, which involve responses to gravity, light, and touch, respectively.

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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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Reptiles are cold-blooded animals. This means that they cannot produce heat in their own bodies, and have to rely on their surroundings to keep warm. This is why most reptiles are found in hot or warm climates. Reptiles like snakes and lizards are this type of animal. Amphibians like frogs, toads, and salamanders are, too. Fish are also cold-blooded animals.

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A mixed gland is a gland that is both exocrine and endocrine, for example, the pancreas. Pancreas is known as a mixed gland because it performs functions of both exocrine and endocrine glands.

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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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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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Tikka disease is not related to the crop of Groundnut, Mustard, or Paddy. Tikka disease, also known as Ascochyta blight, is a fungal disease that affects various plants, including beans, chickpeas, and lentils. The disease is caused by a fungus called Ascochyta and can result in small, circular spots on leaves, stems, and pods of infected plants. These spots can be gray, brown, or black, and may have a dark border. In summary, Tikka disease is not related to the crops of Groundnut, Mustard, or Paddy. It affects plants such as beans, chickpeas, and lentils, and is caused by a fungus called Ascochyta.

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The incubation period for chicken eggs is generally 21 days. This means that after a fertilized egg is laid by a hen and is kept at the appropriate temperature and humidity in an incubator, it will take approximately 21 days for the chick to develop and hatch out of the eggshell. During this period, the egg goes through several stages of development. In the first week, the embryo's circulatory system, nervous system, and digestive system start to form. In the second week, the chick's beak, wings, and claws begin to develop. And in the third week, the chick grows rapidly and prepares to break through the shell using its egg tooth, a small point on its beak. It's important to note that the incubation period can vary slightly depending on factors such as the breed of chicken and the temperature and humidity in the incubator. However, 21 days is the average incubation period for chicken eggs.

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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 jelly-like fluid that fills a cell is called cytoplasm. It is made up of mostly water and salt. Cytoplasm is present within the cell membrane of all cell types and contains all organelles and cell parts. Cytoplasm has various functions in the cell.
Most of the important activities of the cell occur in the cytoplasm. Cytoplasm contains molecules such as enzymes which are responsible for breaking down waste and also aid in metabolic activity.

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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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DNA in eukaryotic cells is contained in the nucleus. The nucleus is a membrane-bound structure found in eukaryotic cells that acts as the "brain" of the cell, controlling and regulating all of its functions. It is also where the cell's DNA is stored and protected, in a substance called chromatin. The DNA in the chromatin is organized into long structures called chromosomes, which are visible during cell division. In short, the nucleus is the place where the DNA of a eukaryotic cell is located and it plays a vital role in the functioning of the cell.

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In the animal's intestine, the oncospheres hatch, invade the intestinal wall, and migrate to the striated muscles, where they develop into cysticerci. A cysticercus can survive for several years in the animal. Humans become infected by ingesting raw or undercooked infected meat.

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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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Primary production in the photic zone is influenced by three major factors—nutrients and light, which are essential for photosynthesis, and grazing pressure, the rate at which the plants are eaten by herbivores.

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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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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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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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The process in which plants use sunlight to synthesize nutrients from carbon dioxide and water is called photosynthesis. Photosynthesis is a crucial process that enables plants to produce their own food and is responsible for releasing oxygen into the atmosphere. During photosynthesis, plants use chlorophyll, a pigment found in their leaves and other green parts, to capture energy from sunlight. This energy is used to combine carbon dioxide and water to produce glucose (a type of sugar) and oxygen. The glucose produced is then used by the plant as an energy source to fuel its growth and other metabolic processes. In summary, photosynthesis is the process by which plants convert sunlight into chemical energy, which they use to synthesize nutrients and sustain their growth and survival.

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