JAMB UTME - Biology - 2018

The role of scolex in tapeworm is to

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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.

Use the diagram to answer the question. The breeding posture illustrated in the diagram is known as

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The breeding posture illustrated in the diagram is known as "amplexus". Amplexus is a mating behavior displayed by many amphibians, in which the male grasps the female with his front legs from behind and holds her in position during mating. This position helps the male to fertilize the eggs as they are laid by the female. Amplexus can be further classified into two types: axillary amplexus, in which the male grasps the female's body just behind the front legs, and inguinal amplexus, in which the male grasps the female's body in the pelvic region. This behavior is critical for the reproduction of many amphibian species, and without it, successful fertilization of the eggs would be less likely to occur.

Which of the following statements is true about sandy soil?

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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.

How many days does it take for incubation of an egg to release chick?

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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.

Double fertilisation is a unique features of

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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.

What is the critical limiting factor for plants below the photic zone in an aquatic ecosystem?

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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.

Which of the following features is not a characteristic of arteries? Arteries

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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

The energy released by 1 gram of glucose is

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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.

Examples of animals with mammary glands include the following except

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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.

In the egg of a bird, the embryo is located in the

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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.

The reason why hospitals use saline solutions as drip instead of water is

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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).

The graph below shows the results of a laboratory investigation which measured the body temperatures of a lizard and a bird under changing artificial conditions. Use it to answer the question.

Which of the statements below is valid?

The part of the ear which contains nerve cells sensitive to sound vibrations is the

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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.

Which is an animal without red blood cells?

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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.

The greatest amount of energy would be obtained by the Oxidation of 100kg of

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The greatest amount of energy would be obtained by the oxidation of 100 kg of sugar. When sugar is oxidized (i.e., burned), it undergoes a process called combustion, which releases energy in the form of heat and light. This energy is stored in the chemical bonds of the sugar molecule, which contain a large amount of potential energy. Sugar is a carbohydrate, and when it is metabolized by the body, it is broken down into glucose molecules, which can be used by cells to produce ATP (adenosine triphosphate), the main source of energy for the body. In fact, glucose is the primary fuel for most cells in the body, including the brain, and is used to produce ATP through a process called cellular respiration. Compared to meat, butter, and biscuits, sugar contains the highest amount of energy per unit weight, or calories. This is because sugar is a highly concentrated source of carbohydrates, while meat, butter, and biscuits contain other nutrients such as protein, fat, and fiber. Therefore, if you were to burn 100 kg of each of these substances, you would obtain the greatest amount of energy from the sugar.

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

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An accurate identification of a rapist can be carried out by conducting DNA analysis. DNA analysis involves collecting and analyzing a sample of DNA from a suspect, such as a hair, skin, or semen sample, and comparing it to a sample of DNA taken from the crime scene. If the DNA profiles match, it can provide strong evidence linking the suspect to the crime. Blood group tests and behavioral tests are not reliable methods for identifying a rapist, as they do not provide a unique identifier like DNA analysis does. Additionally, RNA analysis is not typically used for the identification of rapists. DNA analysis is the most scientifically accepted and accurate method for identifying individuals in criminal investigations, including sexual assault cases.

Swollen, bleeding gums are another common sign of which vitamin?

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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.

The gland that is present close to Trachea

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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.

Examples of micronutrients include the following except

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The essential elements can be divided into macronutrients and micronutrients. Nutrients that plants require in larger amounts are called macronutrients. About half of the essential elements are considered macronutrients: carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur.

Cold blooded animals are referred to as

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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.

Man can contact tapeworm through

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Yes, a person can come into contact with tapeworms by ingesting uncooked or undercooked meat that contains tapeworm larvae. Tapeworms can infect animals such as cows, pigs, and fish, and when humans eat infected meat, they can get infected too. This is why it's important to cook meat thoroughly and to wash fruits and vegetables before eating them. Contact with tapeworms cannot occur through breathing or simple physical contact with an infected person or animal.

Which of the following relationship involves only one organism?

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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.

The yellowish colored liquid component of blood that normally holds the blood cells in suspension is

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Blood plasma is a yellowish liquid component of blood that normally holds the blood cells in whole blood in suspension. In other words, it is the liquid part of the blood that carries cells and proteins throughout the body. It makes up about 55% of the body's total blood volume.

Which of the following animals is cold blooded?

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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.

What would happen if solution Y is more concentrated than solution X in fig 2?

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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.

Which of the following is a mixed gland?

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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.

Study the diagram of a food chain shown and use it to answer the question.

P ---> Q ---> R ---> S ---> T

Which of the following statements best describes the organism designated R? It

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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.

The longest bone in the body is the

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The longest bone in the body is the femur. The femur is located in the thigh region and runs from the hip joint to the knee joint. It is also the strongest bone in the body, designed to support the weight of the body and withstand the forces produced by activities such as running and jumping. The femur's length can vary depending on a person's height, with taller people generally having longer femurs. Overall, the femur plays a critical role in allowing us to walk, run, and engage in other physical activities.

Which of the following processes removes carbon from the atmosphere?

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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.

A beaker of pond water containing few specimens of Euglena was placed in a dark room for two weeks. At the end of this period, the specimens of Euglena were still alive because they were

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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.

Which of the following groups of organisms has kidney as the excretory organ?

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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.

A man who is heterozygous for the disease haemophilia marries a woman who is double recessive for haemophilia. What percentage of their offspring would have the disease?

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Haemophilia is an X-linked recessive genetic disorder. This means that the gene responsible for haemophilia is located on the X chromosome, and individuals with two copies of the defective gene (one inherited from each parent) will have the disease. The man in this scenario is heterozygous, meaning he has one normal X chromosome and one X chromosome with the defective gene. The woman is double recessive, meaning she has two copies of the defective gene. When the man and woman have offspring, each child will inherit one of their father's X chromosomes and one of their mother's X chromosomes. The possible combinations of X chromosomes the children could inherit are: - Normal X chromosome from the father and normal X chromosome from the mother - Normal X chromosome from the father and defective X chromosome from the mother - Defective X chromosome from the father and normal X chromosome from the mother - Defective X chromosome from the father and defective X chromosome from the mother Of these possible combinations, only the last one (defective X chromosome from both parents) will result in the child having haemophilia. The probability of a child inheriting a defective X chromosome from the father is 50%, since the father is heterozygous. The probability of a child inheriting a defective X chromosome from the mother is 100%, since the mother is double recessive. Therefore, the probability of a child inheriting a defective X chromosome from both parents and having haemophilia is 50% x 100% = 50%. So the correct answer is: 50% of their offspring would have the disease.

A plant tissue that carries water and mineral salt is

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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.

A distinguishing feature of mammals is the possession of

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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.

Tikka disease is related with the crop

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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.

A boy who is fond of swimming in a pond finds himself passing urine with traces of blood. He is likely to have contracted

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The boy who is fond of swimming in a pond and passes urine with traces of blood is likely to have contracted schistosomiasis. Schistosomiasis is a parasitic infection caused by a type of flatworm called Schistosoma that commonly inhabits freshwater snails and bodies of water such as ponds and lakes. When a person comes into contact with water contaminated with the parasite, it can penetrate the skin and enter the bloodstream, where it eventually travels to the bladder or intestines and causes inflammation and damage to the tissues. This can lead to symptoms such as blood in the urine or stool, abdominal pain, diarrhea, and anemia. If left untreated, schistosomiasis can lead to chronic health problems such as liver and kidney damage. Therefore, it is important to seek medical attention if experiencing symptoms after swimming or coming into contact with freshwater bodies in endemic areas.

Which of the following structures is not a skeletal material?

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Bone is the substance that forms the skeleton of the body. It is composed chiefly of calcium phosphate and calcium carbonate. Chitin is a major constituent of the exoskeleton, or external skeleton, of many arthropods such as insects, spiders, and crustaceans. The main structural components of our bodies are bone, muscle, and cartilage. Bones are rigid, while muscles bend, stretch, and are flexible. Cartilage connective tissue is the perfect halfway point between these other tissues. It is not as rigid or as hard as bone, and it is also less flexible than muscle. Therefore, we find cartilage in places where we need some support and structure, but a bit of flexibility as well. This includes places such as our joints, our ears, and our nose, as well as in between the vertebrae in our spinal column.

Use the diagram to answer the question. The diagram shows that the organisms are

Accessory material in a chicken egg include the following except

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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.

The immediate product of meiosis in flowering plants is the

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Pollen grains form in the two pollen sacs located in the anther. Each pollen sac contains specialized chambers in which the microspore mother cells are enclosed and protected. The microspore mother cells undergo meiosis to form four haploid microspores. Subsequently, mitotic divisions form four pollen grains. Inside each pollen grain is a generative cell; this cell will later divide to produce two sperm cells. Pollen grain shapes are specialized for specific flower species.