JAMB UTME - Biology - 2018
Question 1 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 2 Report
Which of the following organisms is a primary consumer?
Answer Details
A primary consumer is an organism that feeds on primary producers. Primary consumers are usually herbivores that feed on autotrophic plants, which produce their own food through photosynthesis.
Question 3 Report
Cold blooded animals are referred to as
Answer Details
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.
Question 4 Report
Use the diagram shown to answer the question. In plant cells, the role of the membrane is played by the
Answer Details
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.
Question 5 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 6 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 7 Report
Evidence of evolution include the following except
Answer Details
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.
Question 8 Report
The process in which plant uses sunlight to synthesize nutrients from carbon dioxide and water is called
Answer Details
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.
Question 9 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 10 Report
Spectacles with convex lenses correct long-sightedness by
Answer Details
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.
Question 11 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 12 Report
An example of a radially symmetrical organisms is
Answer Details
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.
Question 13 Report
A boy who is fond of swimming in a pond finds himself passing urine with traces of blood. He is likely to have contracted
Answer Details
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.
Question 14 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 15 Report
Botany is also known as
Answer Details
Botany is also known as "phytology". This term is derived from the Greek word "phyton", which means "plant". Phytology is the scientific study of plants, including their structure, growth, reproduction, metabolism, and classification. It involves the examination of plant anatomy, physiology, ecology, genetics, and evolution. Botanists also study the relationship between plants and their environment, including the interactions between plants and other organisms such as insects, fungi, and bacteria. Overall, phytology is an important field of study that helps us to better understand and appreciate the complexity and diversity of plant life on our planet.
Question 16 Report
Study the diagram of a food chain shown and use it to answer the question.
P ---> Q ---> R ---> S ---> T
The organism designated P in the food chain above is normally sustained by energy from
Answer Details
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.
Question 17 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 18 Report
A pollutant that is mostly associated with acid rain is
Answer Details
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.
Question 19 Report
At which stage in this cycle can a man be infected?
Answer Details
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.
Question 20 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 21 Report
Examples of animals with mammary glands include the following except
Answer Details
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.
Question 22 Report
\
Use the diagram shown to answer the question. After an hour, the level of water in the thistle funnel will
Answer Details
Question 23 Report
Use the diagram shown to answer the question. The experiment above is used to demonstrate the process of
Answer Details
The experiment shown in the diagram is used to demonstrate the process of osmosis. Osmosis is the movement of water molecules across a selectively permeable membrane from an area of high water concentration to an area of low water concentration. In the experiment, the selectively permeable membrane is the potato cell membrane, and the water moves from the area of high concentration (in the beaker) to the area of low concentration (inside the potato). This causes the potato to swell and become heavier as it absorbs the water through osmosis. Thus, the experiment demonstrates the process of osmosis.
Question 24 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 25 Report
A distinguishing feature of mammals is the possession of
Answer Details
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.
Question 26 Report
Which of the following instruments is used to estimate the number of plants in a habitat?
Answer Details
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.
Question 27 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 28 Report
The reason why hospitals use saline solutions as drip instead of water is
Answer Details
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).
Question 29 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 30 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 31 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 32 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 33 Report
Which of the following groups of organisms has kidney as the excretory organ?
Answer Details
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.
Question 34 Report
The cytoplasm of a cell is considered a very important component because it
Answer Details
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.
Question 35 Report
The greatest amount of energy would be obtained by the Oxidation of 100kg of
Answer Details
To determine which of the given food items provides the greatest amount of energy upon oxidation, we need to compare their caloric content. Here's a general overview of the approximate caloric values per 100 grams for each type of food:
- Meat: Approximately 250 calories (varies depending on the type and cut of meat)
- Butter: Approximately 717 calories
- Sugar: Approximately 387 calories
- Biscuits: Approximately 450 calories (varies depending on ingredients and recipe)
Now, let's scale these values up to 100 kg (100,000 grams):
- Meat: 250 \, \text{calories/100g} \times 1000 = 250,000 \, \text{calories}250calories/100g×1000=250,000calories
- Butter: 717calories/100g×1000=717,000calories
- Sugar: 387calories/100g×1000=387,000calories
- Biscuits: 450calories/100g×1000=450,000calories
From these calculations, butter has the highest caloric content per 100 kg. Therefore, the greatest amount of energy will be obtained by the oxidation of 100 kg of:
B. butter
Question 36 Report
Double fertilisation is a unique features of
Answer Details
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.
Question 37 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 38 Report
Blood circulation in a mammal is said to be double because
Answer Details
The majority of mammals (including humans) utilize a double circulatory system. This means we have two loops in our body in which blood circulates. One is oxygenated, meaning oxygen rich, and the other is deoxygenated, which means it has little to no oxygen, but a lot of carbon dioxide.
Question 39 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 40 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.
