JAMB UTME - Biology - 2018
Question 1 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 2 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 3 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 4 Report
The curvature movement of plants in response to the stimulus of water is called
Answer Details
The curvature movement of plants in response to the stimulus of water is called "hydrotropism." Hydrotropism is a type of plant movement that occurs when a plant's roots grow towards a source of water. This is an important mechanism that allows plants to find water and nutrients in the soil. When a plant is exposed to a source of water, such as a moist patch of soil, the plant's roots will start to grow towards the water. This is because the cells on the side of the root closest to the water absorb more water and expand, causing the root to bend towards the source of water. As the root grows towards the water, it will continue to bend until it reaches the water source. Hydrotropism is different from other types of plant movements, such as geotropism, phototropism, and thigmotropism, which involve responses to gravity, light, and touch, respectively.
Question 5 Report
The role of scolex in tapeworm is to
Answer Details
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.
Question 6 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 7 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 8 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 9 Report
The function of pith in plant is
Answer Details
Pith, or medulla, is a tissue in the stems of vascular plants. Pith is composed of soft, spongy parenchyma cells, which store and transport nutrients throughout the plant. In eudicots, pith is located in the center of the stem. In monocots, it extends also into flowering stems and roots.
Question 10 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 11 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 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
Use the diagram to answer the question. The diagram shows that the organisms are
Answer Details
Question 14 Report
Long neck in giraffe is used to illustrate the theory of
Answer Details
The giraffe's long neck is a perfect adaptation to the animal's natural habitat. Clearly the giraffe evolved this uncommon and helpful trait in order to reach those nourishing leaves. That's how natural selection works. Use and disuse' theory in human life advocate the idea that animals acquired characteristics after using certain physical traits constantly.
Question 15 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 16 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 17 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 18 Report
Which of the following relationship involves only one organism?
Answer Details
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.
Question 19 Report
Mineral salts can be absorbed into roots by
Answer Details
In plants and animals, mineral absorption, also called mineral uptake is the way in which minerals enter the cellular material, typically following the same pathway as water. In plants, the entrance portal for mineral uptake is usually through the roots by a process of diffusion and active transport.
Question 20 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 21 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 22 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 23 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 24 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 26 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 27 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 28 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 29 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 30 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 31 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 32 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 33 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 34 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 35 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 36 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 37 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 38 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 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 yellowish colored liquid component of blood that normally holds the blood cells in suspension is
Answer Details
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.
