JAMB UTME - Biology - 2018
Question 1 Report
Accessory material in a chicken egg include the following except
Answer Details
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.
Question 2 Report
Etiolation is causes by the influence of
Answer Details
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.
Question 3 Report
A plant tissue that carries water and mineral salt is
Answer Details
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.
Question 4 Report
Which of the following features is not a characteristic of arteries? Arteries
Answer Details
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
Question 5 Report
The four classes of cnidarian include the following except
Answer Details
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.
Question 6 Report
Cytokinesis of mitosis is a process that ensures that
Answer Details
Cytokinesis is the final stage of mitosis, the process by which a cell divides to form two identical daughter cells. During cytokinesis, the cytoplasm of the original cell is divided into two parts, with each part containing a complete set of genetic material (chromosomes). The main purpose of cytokinesis is to ensure that each daughter cell receives a complete set of genetic material and the necessary organelles to function properly. This is important because if one daughter cell received more genetic material or more organelles than the other, it could lead to problems such as cell death or mutations. Therefore, "each daughter cell gets the necessary organelles" is the correct label to associate with the question above. While the other options may be important aspects of mitosis, they do not directly relate to the role of cytokinesis in ensuring that each daughter cell receives a complete and functional set of genetic material and organelles.
Question 7 Report
The hygrometer is used for measuring
Answer Details
A hygrometer is an instrument used to measure the amount of humidity and water vapor in the atmosphere, in soil, or in confined spaces. Humidity measurement instruments usually rely on measurements of some other quantity such as temperature, pressure, mass, a mechanical or electrical change in a substance as moisture is absorbed. By calibration and calculation, these measured quantities can lead to a measurement of humidity.
Question 8 Report
What is the critical limiting factor for plants below the photic zone in an aquatic ecosystem?
Answer Details
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.
Question 9 Report
The outer membrane that covers the brain is
Answer Details
The outer membrane that covers the brain is called the "dura mater". It is a thick, tough, and fibrous layer that provides protection and support to the brain. The dura mater is the outermost layer of the three meninges (the protective membranes that surround the brain and spinal cord). It lies closest to the skull and forms a barrier that separates the brain from the bones of the skull. The dura mater contains blood vessels and nerves that supply the brain and is responsible for anchoring the brain in place.
Question 10 Report
The temporary union of two organisms and the exchange of micronuclear elements is called
Answer Details
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.
Question 11 Report
The vitamin which is important in the formation of the retina pigment is
Answer Details
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.
Question 12 Report
Use the diagram to answer the question. The breeding posture illustrated in the diagram is known as
Answer Details
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.
Question 13 Report
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
Answer Details
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.
Question 14 Report
Which of the following cycles involves the process of precipitation and transpiration?
Answer Details
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.
Question 15 Report
The flippers of a whale and the fins of a fish are examples of
Answer Details
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.
Question 16 Report
Maltose is combination of glucose and
Answer Details
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.
Question 17 Report
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?
Answer Details
Question 18 Report
How many days does it take for incubation of an egg to release chick?
Answer Details
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.
Question 19 Report
A seed of a flowering plant can best be described as
Answer Details
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth with in the motherplant.
Question 20 Report
The reason why the flow of blood through the capillaries is very slow is
Answer Details
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.
Question 21 Report
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.
What physiological term can used to describe the regulation of the body temperature of the of the lizard?
Answer Details
The physiological term that can be used to describe the regulation of the body temperature of the lizard is "poikilothermy". Poikilothermy refers to the ability of an animal's body temperature to fluctuate with changes in the external environment. In other words, the body temperature of poikilothermic animals, such as lizards, is not actively regulated by their bodies, but rather is influenced by the temperature of their surroundings. As seen in the graph, the body temperature of the lizard varies with the temperature of the environment it is in. This is in contrast to homeothermic animals, such as birds and mammals, which can maintain a relatively constant body temperature regardless of external temperature changes through the process of "thermoregulation".
Question 22 Report
The gland that is present close to Trachea
Answer Details
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.
Question 23 Report
Red blood cells were found to have burst open after being placed in distill for an hour. This phenomenon is known as
Answer Details
The phenomenon you're referring to is called haemolysis. Haemolysis is the bursting of red blood cells when they are placed in a solution that is different from their normal environment. When red blood cells are placed in distilled water, the water moves into the cells and causes them to expand and eventually burst, resulting in haemolysis. This occurs because the concentration of solutes (e.g. salts, sugars) is higher inside the red blood cells than in the distilled water, causing water to move into the cells and causing them to burst. In simple terms, haemolysis is the bursting of red blood cells due to a change in the solution they are in.
Question 24 Report
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Use the diagram shown to answer the question. After an hour, the level of water in the thistle funnel will
Answer Details
Question 25 Report
Which of the following statements is true about sandy soil?
Answer Details
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.
Question 26 Report
The hormones secreted by pancreas serves to
Answer Details
The production of pancreatic hormones, including insulin, somatostatin, gastrin, and glucagon, play an important role in maintaining sugar and salt balance in our bodies.
Question 27 Report
Physiological adaptation to very dry conditions in animal demonstrates
Answer Details
Aestivation is a state of animal dormancy, similar to hibernation, although taking place in the summer rather than the winter. Aestivation is characterized by inactivity and a lowered metabolic rate, that is entered in response to high temperatures and arid conditions.
Question 28 Report
What is the function of contractile vacuole in paramecium?
Answer Details
The contractile vacuole in paramecium functions to get rid of excess water. Paramecium is a single-celled organism that lives in freshwater environments. As water enters the cell by osmosis, the contractile vacuole collects and pumps out the excess water to prevent the cell from swelling and potentially bursting. The contractile vacuole acts like a pump, contracting and releasing to expel the excess water out of the cell. This process helps maintain the proper balance of water and ions inside the cell, which is necessary for the organism's survival. Therefore, the function of the contractile vacuole in paramecium is to regulate water balance and prevent the cell from bursting due to excess water intake.
Question 29 Report
The vessel carrying oxygenated blood to the tissues is
Answer Details
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.
Question 30 Report
Which of the following diseases is not hereditary?
Answer Details
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.
Question 31 Report
In the egg of a bird, the embryo is located in the
Answer Details
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.
Question 32 Report
The energy released by 1 gram of glucose is
Answer Details
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.
Question 33 Report
A group of closely related organisms capable of interbreeding to produce the fertile offspring are known as members of a
Answer Details
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.
Question 34 Report
Which is an animal without red blood cells?
Answer Details
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.
Question 35 Report
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?
Answer Details
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.
Question 36 Report
Which of the following is a mixed gland?
Answer Details
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.
Question 37 Report
Examples of micronutrients include the following except
Answer Details
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.
Question 38 Report
Total salt content in blood is about
Answer Details
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.
Question 39 Report
The part of the ear which contains nerve cells sensitive to sound vibrations is the
Answer Details
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.
Question 40 Report
Ozone hole refers to
Answer Details
Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.
