JAMB UTME - Biology - 2018
Ibeere 1 Ìròyìn
A plant tissue that carries water and mineral salt is
Awọn alaye Idahun
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.
Ibeere 2 Ìròyìn
Mineral salts can be absorbed into roots by
Awọn alaye Idahun
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.
Ibeere 3 Ìròyìn
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
Awọn alaye Idahun
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.
Ibeere 4 Ìròyìn
The energy released by 1 gram of glucose is
Awọn alaye Idahun
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.
Ibeere 5 Ìròyìn
Which of the following statements is true about sandy soil?
Awọn alaye Idahun
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.
Ibeere 6 Ìròyìn
Use the diagram shown to answer the question. The experiment above is used to demonstrate the process of
Awọn alaye Idahun
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.
Ibeere 7 Ìròyìn
Which of the following diseases is not hereditary?
Awọn alaye Idahun
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.
Ibeere 8 Ìròyìn
Examples of animals with mammary glands include the following except
Awọn alaye Idahun
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.
Ibeere 9 Ìròyìn
Which of the following instruments is used to estimate the number of plants in a habitat?
Awọn alaye Idahun
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.
Ibeere 11 Ìròyìn
The hormones secreted by pancreas serves to
Awọn alaye Idahun
The production of pancreatic hormones, including insulin, somatostatin, gastrin, and glucagon, play an important role in maintaining sugar and salt balance in our bodies.
Ibeere 12 Ìròyìn
An example of a radially symmetrical organisms is
Awọn alaye Idahun
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.
Ibeere 13 Ìròyìn
Which of the following relationship involves only one organism?
Awọn alaye Idahun
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.
Ibeere 14 Ìròyìn
What would happen if solution Y is more concentrated than solution X in fig 2?
Awọn alaye Idahun
Osmosis is the spontaneous net movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides.
Ibeere 15 Ìròyìn
The flippers of a whale and the fins of a fish are examples of
Awọn alaye Idahun
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.
Ibeere 16 Ìròyìn
Blood circulation in a mammal is said to be double because
Awọn alaye Idahun
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.
Ibeere 17 Ìròyìn
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?
Awọn alaye Idahun
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.
Ibeere 18 Ìròyìn
The outer membrane that covers the brain is
Awọn alaye Idahun
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.
Ibeere 19 Ìròyìn
Use the diagram to answer the question. The breeding posture illustrated in the diagram is known as
Awọn alaye Idahun
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.
Ibeere 20 Ìròyìn
In the egg of a bird, the embryo is located in the
Awọn alaye Idahun
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.
Ibeere 21 Ìròyìn
The role of scolex in tapeworm is to
Awọn alaye Idahun
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.
Ibeere 22 Ìròyìn
Etiolation is causes by the influence of
Awọn alaye Idahun
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.
Ibeere 24 Ìròyìn
Long neck in giraffe is used to illustrate the theory of
Awọn alaye Idahun
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.
Ibeere 25 Ìròyìn
The yellowish colored liquid component of blood that normally holds the blood cells in suspension is
Awọn alaye Idahun
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.
Ibeere 26 Ìròyìn
Ozone hole refers to
Awọn alaye Idahun
Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.
Ibeere 27 Ìròyìn
How many days does it take for incubation of an egg to release chick?
Awọn alaye Idahun
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.
Ibeere 28 Ìròyìn
Man can contact tapeworm through
Awọn alaye Idahun
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.
Ibeere 29 Ìròyìn
The curvature movement of plants in response to the stimulus of water is called
Awọn alaye Idahun
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.
Ibeere 30 Ìròyìn
A group of organism of the same species living together in a particular area is described as
Awọn alaye Idahun
The term that describes a group of organisms of the same species living together in a particular area is "population".
A population refers to all the individuals of a particular species that live in a specific geographic area and can interbreed. For example, a population of deer in a forest or a population of fish in a river.
On the other hand, a "colony" typically refers to a group of organisms of the same species living closely together, but it usually implies a degree of cooperation and organization beyond what is typically seen in a population.
A "community" refers to all the different populations of organisms living together in a particular area and interacting with each other, such as a community of plants, animals, and microbes in a forest.
Lastly, a "niche" refers to the particular role and position that a species has in its environment, including the resources it uses and the interactions it has with other species.
Ibeere 31 Ìròyìn
The temporary union of two organisms and the exchange of micronuclear elements is called
Awọn alaye Idahun
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.
Ibeere 32 Ìròyìn
Swollen, bleeding gums are another common sign of which vitamin?
Awọn alaye Idahun
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.
Ibeere 33 Ìròyìn
Which of the following structures is not a skeletal material?
Awọn alaye Idahun
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.
Ibeere 34 Ìròyìn
Name the blood cells in which nucleus is absent
Awọn alaye Idahun
Like red cells, platelets (thrombocytes) have no nucleus. However, unlike red cells that originate in the marrow as nucleated cells and lose their nucleus, platelets are produced by budding off from a giant multinucleated marrow cell called a megakaryocyte.
Ibeere 35 Ìròyìn
Which of the following cycles involves the process of precipitation and transpiration?
Awọn alaye Idahun
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.
Ibeere 36 Ìròyìn
Which of the following groups of organisms has kidney as the excretory organ?
Awọn alaye Idahun
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.
Ibeere 37 Ìròyìn
What is the critical limiting factor for plants below the photic zone in an aquatic ecosystem?
Awọn alaye Idahun
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.
Ibeere 38 Ìròyìn
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
Awọn alaye Idahun
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.
Ibeere 39 Ìròyìn
The gland that is present close to Trachea
Awọn alaye Idahun
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.
Ibeere 40 Ìròyìn
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?
Awọn alaye Idahun
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".
