JAMB UTME - Biology - 2018
Question 1 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 2 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 3 Report
An animal which is active during the day is known as a
Answer Details
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.
Question 4 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 5 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 6 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 7 Report
The damage to ozone layer is caused by
Answer Details
Ozone sits in the upper atmosphere and absorbs ultraviolet radiaton, another type of solar energy that's harmful to humans, animals and plants. CFCs and halons cause chemical reactions that break down ozone molecules, reducing ozone's ultraviolet radiation-absorbing capacity. Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.
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
Swollen, bleeding gums are another common sign of which vitamin?
Answer Details
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.
Question 10 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 11 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 12 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 13 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 14 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 15 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 16 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 17 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 18 Report
Which of the following animals is cold blooded?
Answer Details
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.
Question 19 Report
Man can contact tapeworm through
Answer Details
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.
Question 20 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 21 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 23 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 24 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 25 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 26 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 27 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 28 Report
What is the function of trichocyst in paramecium?
Answer Details
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.
Question 29 Report
Which of the following processes removes carbon from the atmosphere?
Answer Details
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.
Question 30 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 31 Report
Which of the following structures is not a skeletal material?
Answer Details
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.
Question 32 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 33 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 34 Report
Use the diagram to answer the question. The diagram shows that the organisms are
Answer Details
Question 35 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 36 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 37 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 38 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.
Question 39 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 40 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
