JAMB UTME - Biology - 2019

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The organism that changes light energy into stored chemical energy in an ecosystem is the producer. Producers are typically plants and algae that use photosynthesis to convert light energy from the sun into chemical energy stored in the form of glucose (sugar). This stored energy is then used as a source of food and energy for other organisms in the ecosystem. Consumers, on the other hand, are organisms that consume producers or other consumers to obtain energy. Decomposers are organisms that break down dead organic matter and return nutrients to the soil. Carnivores are consumers that eat other consumers. So, in summary, the producer is the organism that converts light energy into stored chemical energy, while consumers, decomposers, and carnivores obtain energy by eating other organisms.

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The specific portion of a habitat that is occupied by a particular species is referred to as its "Ecological Niche". An ecological niche refers to the role and position a species has in its environment, including its relationships with other species, the way it obtains food and resources, and the physical conditions it requires to survive. Essentially, it's the species' unique way of life and how it fits into its habitat. For example, a bird species might have a specific ecological niche as a seed-eater, and it might occupy a certain area of a forest where seeds are abundant. Another species might occupy a different niche as a predator, hunting for insects in a different part of the forest. These two species have their own unique ecological niches and do not overlap in the way they interact with their environment.

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Mutation is the change in the genetic make up of an organism, which results in a new inheritable characteristic. Simply put, a mutation is a change in an organism's DNA that can be passed down to future generations. Mutations can happen naturally or can be caused by environmental factors such as exposure to radiation or chemicals. These changes can result in a variety of effects, from a simple alteration in an organism's appearance to a serious medical condition.

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The tapeworm possesses a thin membrane mostly because of it absorption of digested food from the intestine of the host.

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In plants, respiration occurs in all living cells. Respiration is the process by which cells break down glucose to release energy that is necessary for the plant to carry out its life processes, such as growth, maintenance, and reproduction. While the stomata and lenticels are structures involved in gas exchange, they do not carry out the process of respiration. Similarly, while mesophyll cells are specialized cells involved in photosynthesis, they are not the only cells involved in respiration. All living cells, including those in the roots, stems, leaves, and reproductive organs, carry out respiration to produce energy. The oxygen needed for respiration enters the cells through the stomata and is transported to the cells by the circulatory system of the plant. The carbon dioxide produced by respiration is released from the cells and can be used by nearby cells for photosynthesis. In summary, respiration occurs in all living cells in plants and is a crucial process for plant survival and growth.

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Fats have the highest amount of energy in joules per unit weight compared to carbohydrates, proteins, and vitamins. This is because fats contain more carbon and hydrogen atoms than carbohydrates and proteins, and these atoms have a higher potential to release energy when they are broken down and burned during cellular respiration. One gram of fat provides about 9 calories (37.7 kJ) of energy, while one gram of carbohydrates or proteins provides only about 4 calories (16.7 kJ) of energy. Vitamins, on the other hand, are not significant sources of energy and play important roles in supporting various metabolic processes in the body. To put it simply, fats contain more energy per unit weight than other substances because they are made up of more energy-rich carbon and hydrogen atoms.

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Viruses are not the pathogens of Tuberculosis. Tuberculosis is caused by the bacterium Mycobacterium tuberculosis. While viruses can weaken the immune system, making it more susceptible to other infections, including tuberculosis, the actual cause of tuberculosis is the bacterium, not a virus.

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Turbidity is not typically considered a factor in a terrestrial habitat. A terrestrial habitat is a place where land-dwelling organisms, such as plants and animals, live and interact with their environment. Temperature, sunlight, and humidity are all important factors in determining the characteristics of a terrestrial habitat and the organisms that live there. Temperature affects the rate of biochemical reactions in organisms, while sunlight provides energy for photosynthesis in plants and affects the behavior of many animals. Humidity, or the amount of moisture in the air, can affect the water balance of plants and animals. On the other hand, turbidity refers to the cloudiness or haziness of a fluid, such as water, due to the presence of suspended particles. Turbidity is typically associated with aquatic habitats, where it can affect the penetration of light and the availability of nutrients for aquatic plants and animals. In a terrestrial habitat, there is generally no water for particles to be suspended in, so turbidity is not usually a significant factor.

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The Cowper's gland, also known as the bulbourethral gland, secretes a part of the seminal fluid in mammals. This gland is located near the base of the penis and its secretion is added to the semen just before ejaculation. The fluid produced by the Cowper's gland is alkaline and helps to neutralize the acidity of the female reproductive tract. This is important because it helps to create a more favorable environment for the sperm, increasing the chances of successful fertilization. The alkaline fluid also helps to protect the sperm from the corrosive effects of the acidic environment in the female reproductive tract. So, the Cowper's gland plays a crucial role in the reproductive process of mammals.

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The effect of using artificial pollination in plant breeding is "Improvement of the variety of crops". Artificial pollination is the process of manually transferring pollen from one flower to another to fertilize it, with the goal of producing hybrid plants with desirable traits. This allows plant breeders to combine traits from two different plants to create a new variety with improved qualities such as increased yield, disease resistance, and improved flavor. By using artificial pollination, plant breeders can control the genetics of the resulting offspring, leading to the creation of new crop varieties with improved traits. This can help to increase food production and improve the quality of crops, making them more resilient and better suited for different growing conditions.

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The juice that contains the enzyme ptyalin is saliva. Ptyalin, also known as salivary amylase, is an enzyme that breaks down complex carbohydrates into simple sugars. It is produced by the salivary glands and released into the mouth when we eat. Ptyalin begins the process of digestion in the mouth, breaking down starchy foods such as bread and potatoes into smaller, more easily digestible molecules. Gastric juice is produced by the stomach and contains hydrochloric acid and enzymes that help break down proteins. Succus is not a specific type of juice. It can refer to any juice that is extracted from a plant or fruit. Pancreatic juice is produced by the pancreas and contains enzymes that help break down proteins, carbohydrates, and fats in the small intestine. So, the correct answer is saliva.

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The theory of natural selection stated by Charles Darwin is not "Characteristics acquired through use or disuse are transmitted to offspring". This idea is sometimes referred to as "Lamarkism," and it was popular before Darwin's theory of natural selection became widely accepted. The theory of natural selection states that variations that are beneficial for survival and reproduction are more likely to be passed on to the next generation, while variations that are harmful are less likely to be passed on. However, the theory does not suggest that the use or disuse of a particular trait can directly cause it to be transmitted to offspring. Instead, the transmission of traits is determined by the genetic information that is passed from parents to offspring.

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Discontinuous variation is the differences of variations in behaviour by which organisms can be grouped into 2 or more classes within a population without any intermediates among them e.g Behaviour, ability to roll tongue.

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The glomerular filtrate contains all of the substances listed except blood corpuscles. The glomerular filtrate is a fluid that is filtered from the blood in the kidneys through a specialized structure called the glomerulus. This fluid contains water, small molecules like glucose, amino acids, and urea, and ions like sodium, potassium, and chloride. Blood corpuscles, also known as blood cells, are not normally present in the glomerular filtrate because they are too large to pass through the small pores in the glomerular capillaries. Blood cells are important components of blood that help to transport oxygen, fight infection, and support the body's immune system. The glomerular filtrate is a crucial step in the process of urine formation, as it allows for the selective reabsorption of important substances like water and glucose while removing waste products like urea. The remaining fluid is then processed by the kidney tubules to form urine, which is eventually excreted from the body. It is important to note that the composition of the glomerular filtrate can vary depending on a person's diet, hydration status, and overall health, and that disorders of the kidneys can affect the ability of the kidneys to filter and process this fluid correctly.

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The type of nutrition in which two organisms of different species live together and derive nutrients from each other is called symbiotic nutrition. In symbiotic nutrition, the two different species of organisms live together in a close relationship and mutually benefit from each other. One organism provides nutrients, such as food or shelter, to the other organism, and in return, the other organism provides nutrients or some other benefit to the first organism. This type of nutrition is also known as mutualism. Symbiotic nutrition can be found in various forms in nature. For example, the rhizobia bacteria live in the root nodules of leguminous plants and fix atmospheric nitrogen into a form that the plants can use. In return, the plants provide the bacteria with sugars and other nutrients. Another example is lichens, which are made up of a fungus and an alga living together. The fungus provides a protected environment for the alga, while the alga provides the fungus with sugars and other nutrients through photosynthesis. So, the correct answer is "symbiotic nutrition".

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Competition among individuals of a population increases the "Survival of the fittest". This means that individuals that are better adapted to their environment and can compete more effectively for resources are more likely to survive and reproduce, passing on their advantageous traits to their offspring. Over time, this process can lead to the evolution of a population and can result in the survival of the strongest, most fit individuals. In a simple way, it's like a race where the fastest runner wins and gets to advance to the next round. Similarly, in a population, the individuals who are best equipped to survive and thrive will be more likely to do so, while those who are not as well adapted may struggle and eventually die off.

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Operculum or gill cover helps the tilapia fish in gaseous exchange.

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The raw materials required by green plants to manufacture their food are mainly inorganic substances. During photosynthesis, green plants use energy from sunlight to convert carbon dioxide from the air and water from the soil into glucose, a type of sugar that they use as food. The inorganic substances required for this process include carbon dioxide, water, and a few mineral nutrients such as nitrogen, phosphorus, and potassium, which the plants absorb from the soil through their roots. Although green plants do require fluids, such as water, and gases, such as carbon dioxide, for photosynthesis, these materials are considered inorganic because they do not contain carbon-hydrogen bonds, which are characteristic of organic molecules. Thus, the main raw materials required by green plants for photosynthesis are inorganic substances.

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Tadpole's ability to swim and adapt to an aquatic habitat is due to the presence of its tail.

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The type of vertebrate that assists in breathing alongside the ribs are thoracic vertebrates. The thoracic region of the spine is located in the upper and middle back, and it is the region that supports the ribcage. In thoracic vertebrates, the ribs are attached to the vertebrae and to the sternum, or breastbone, forming a protective cage around the heart and lungs. During breathing, the diaphragm muscle contracts and flattens, which increases the volume of the chest cavity and draws air into the lungs. At the same time, the ribcage expands, which further increases the volume of the chest cavity and helps to pull air into the lungs. The ribs play a crucial role in this process by expanding and contracting with each breath. In addition to the diaphragm muscle, the muscles between the ribs, called intercostal muscles, also contract and relax to help move air in and out of the lungs. Sacral, caudal, and lumbar vertebrates do not have the same type of ribcage as thoracic vertebrates and therefore do not rely on the expansion and contraction of ribs for breathing. Instead, these vertebrates have other adaptations that allow them to breathe efficiently in their respective environments. For example, fish extract oxygen from water through their gills, while reptiles and some mammals, such as whales and dolphins, can hold their breath for long periods of time underwater.

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The statement that is correct about the similarities in plant and animal transport is that materials and hormones are transported in fluid form. In both plants and animals, the transport of materials and hormones occurs through the use of fluids. In animals, blood serves as the transport medium, carrying oxygen, nutrients, and hormones to various tissues and organs. In plants, the transport medium is called sap, and it contains water, minerals, and sugars that are transported through specialized tissues called xylem and phloem. However, the other options provided in the question are incorrect. In animals, blood is made up of a variety of different tissues, not just one. And in plants and animals, materials are not transported in the same vessels. In animals, materials are transported through veins and arteries, while in plants, they are transported through xylem and phloem. Finally, while diffusion is important in both plant and animal transport, it is not the only mechanism by which materials are moved.

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Rabbits cannot survive in an aquatic habitat because they have no gills. Gills are specialized organs that allow fish and other aquatic animals to extract oxygen from water. Without gills, rabbits would be unable to breathe underwater and would quickly suffocate. Additionally, rabbits are not built for an aquatic lifestyle. They have short legs and are not adapted for swimming or propelling themselves through water. While they may be able to paddle around for a short period of time, they would eventually tire and be unable to keep themselves afloat. This is why rabbits are best suited to a terrestrial habitat where they can easily breathe and move around.

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Artecology is the study of an individual organism or a single specie of organism and no environment

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The association between two organisms living together in which only one benefits from the association while the other is neither benefited nor harmed is called commensalism. Commensalism is a type of ecological relationship that occurs when one organism benefits from the association, while the other organism is unaffected. The organism that benefits from the association is called the commensal, while the other organism is called the host. In this type of relationship, the commensal often uses the host for shelter, food, or transportation, but the host is not harmed or helped by the commensal in any way. For example, some birds and mammals, such as egrets and cattle, have a commensal relationship. The birds perch on the backs of the cattle and eat insects that are attracted to the cattle. The cattle are not affected by the presence of the birds, but the birds benefit from the association by gaining a steady source of food. In summary, commensalism is a type of ecological relationship in which one organism benefits from the association while the other is neither benefited nor harmed.

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Dictating the formation of a protein by a gene in a chromosome is a process of transmitting hereditary characteristics

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A population is best described as a group of individuals of the same species that live together in the same area and can potentially interact with each other. For example, a population of deer living in a forest would consist of all the individual deer of the same species that live in that forest and are able to mate with each other. This definition excludes which includes plants and animals of different species living together, and which includes different species of wild animals. includes only a specific subset of organisms, and is not a comprehensive definition of a population.

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Thunderstorms can be beneficial to plants because they add nitrogen to the soil. Lightning is an electrical discharge that can break apart nitrogen molecules in the air, and the resulting nitrogen compounds can fall to the ground in rainwater. Plants need nitrogen to grow, and thunderstorms can provide a natural source of this essential nutrient. However, it's important to note that while thunderstorms can bring benefits, they can also bring harm in the form of lightning strikes and flooding, so it's important to take necessary precautions to protect yourself and your property during severe weather.

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Genes are the inheritable character/features possessed by an organism. They are the basic unit of heredity and carry information from one generation to the next. A gene is a segment of DNA that contains the instructions for making a specific protein. The proteins made by genes control the growth, development, and function of our bodies. Each of us has many thousands of genes, which together determine our traits and characteristics. So, genes are the underlying cause of the traits and characteristics that are passed down from parent to offspring.

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Starch is the main and first product formed during photosynthesis because the simple sugar formed is partly used by the plant and excess of it is converted into starch immediately for storage and the starch is transported to other parts of the plant through the phloem vessels for storage.

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The cerebrum controls all voluntary actions. The cerebrum is the largest part of the brain and is responsible for controlling movement, sensation, thought, and emotion. It is divided into two hemispheres, the left and the right, each of which controls different functions. The cerebrum is responsible for conscious decision making and voluntary movements, such as moving your arm or leg. The other options you listed, the olfactory lobes, hypothalamus, and pons varolii, have different functions in the brain. The olfactory lobes are responsible for the sense of smell, the hypothalamus controls basic functions like hunger and thirst, and the pons varolii is involved in breathing and other autonomic functions.

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The correct answer is: "Fusion of sperm and egg nuclei" Fertilization is the process in which a male gamete (sperm) combines with a female gamete (egg or ovum) to form a zygote, which is the first cell of the new organism. In higher organisms, including humans, fertilization occurs when a sperm cell penetrates the outer membrane of the egg cell and fuses with the egg's nucleus, resulting in the fusion of genetic material from both the sperm and the egg. The other options listed are not examples of fertilization. - Pollen grain landing on a sticky stigma is a process called pollination, which occurs in plants. Pollen grains contain male gametes, but pollination is not the same as fertilization, as the male and female gametes do not actually combine until after the pollen tube grows down into the ovule and the sperm cells are released to fuse with the egg. - Ejaculation of the egg and pollen grain is not a biological process that occurs in any known organism. - Ejaculation of sperm into the female body is the first step in the process of fertilization, but it is not fertilization itself. The sperm must still reach and penetrate the egg to complete the process of fertilization.

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Green plants are autotropic. This means that they are able to produce their own food through a process called photosynthesis. During photosynthesis, plants use energy from sunlight, carbon dioxide from the air, and water from the soil to produce glucose, which is their source of energy. This characteristic sets plants apart from animals and other organisms that are heterotrophic and rely on other organisms for their food.

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Height in humans is an example of continuous variation. This means that there is a wide range of possible heights within a population and that there is no clear division into separate categories. People can be tall, short, or anywhere in between, and there is a smooth distribution of heights rather than distinct groups. This type of variation is called continuous because the traits can take on any value within a range, rather than being limited to specific categories.

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The pair of scientists who discovered the Rhesis factor in human blood is Landsteiner and Levine. Karl Landsteiner was an Austrian biologist and physician who is best known for his discovery of the ABO blood group system. In 1940, he and his colleague Alexander S. Wiener discovered the Rh factor, which is a protein that is found on the surface of red blood cells in some individuals and can cause an immune response in others. This discovery was a significant breakthrough in the field of blood transfusion and helped to reduce the risk of transfusion reactions in patients. Levine is likely a reference to Philip Levine, an American immunologist who worked with Landsteiner and Wiener at the Rockefeller Institute for Medical Research in New York. Levine played a key role in the discovery of the Rh factor, conducting many of the experiments that helped to confirm the existence of the protein. Neither Hooke nor Darwin were involved in the discovery of the Rh factor in human blood. Robert Hooke was a 17th-century English scientist who made important contributions to the fields of microscopy, physics, and biology, while Charles Darwin was a 19th-century British naturalist who is best known for his theory of evolution by natural selection. In summary, the correct answer is Landsteiner and Levine, as they were the scientists who discovered the Rh factor in human blood.

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Albinism is an expression of a trait controlled by recessive genes. Albinism is a genetic condition that results in a lack of melanin, a pigment that provides color to the skin, hair, and eyes. The condition is caused by mutations in genes that produce or distribute melanin. In order for an individual to have albinism, they must inherit two copies of the mutated gene, one from each parent. If an individual inherits one normal gene and one mutated gene, they will not have albinism, but they will be a carrier of the condition and can pass it on to their offspring. This is why albinism is considered a recessive trait, meaning it is only expressed when two copies of the mutated gene are present. So, in summary, albinism is an expression of a trait controlled by recessive genes, meaning that it is caused by mutations in genes that produce or distribute melanin, and it is only expressed when two copies of the mutated gene are present.

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Reading the verdict of a case by a magistrate is an example of a voluntary action. Voluntary actions are those actions that require conscious effort and decision-making. In this case, the magistrate has to actively choose to read the verdict and make a conscious effort to understand and communicate the decision to those involved in the case. It is not a reflex action, as it does not occur automatically in response to a stimulus. It is also not an instinct or a conditioned reflex, as it is not a natural behavior or a learned response to a particular situation.

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The appendix can be considered vestigial in humans but functional in other mammals. The appendix is a small pouch-like organ attached to the large intestine. In many other mammals, the appendix serves as a functional part of the digestive system, helping to break down cellulose and other tough plant materials that are difficult to digest. However, in humans, the appendix is considered vestigial, which means it is a structure that has lost its original function over the course of evolution. While the appendix may have had a digestive function in our distant ancestors, today it appears to have no essential role in our digestive system. However, the appendix does contain lymphoid tissue, which plays a role in the immune system, particularly during early childhood. This suggests that the appendix may still have some function in the immune system, though its exact role is not yet fully understood. In rare cases, the appendix can become inflamed and infected, leading to a condition called appendicitis. If left untreated, appendicitis can be life-threatening. In such cases, the appendix is removed through surgery, and the individual can still live a healthy life without any ill effects. In summary, the appendix is considered vestigial in humans, meaning it has lost its original function in the course of evolution. While it may still have some minor immune-related functions, it is not considered essential for human health, and in some cases, it can even be harmful if it becomes infected.

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The attachment of the embryo to the wall of the uterus is called implantation. After a sperm fertilizes an egg, the resulting single cell, called a zygote, begins to divide and form a ball of cells known as a blastocyst. The blastocyst then travels down the fallopian tube and into the uterus, where it must implant, or attach itself, to the wall of the uterus in order to continue developing. Implantation is a complex process that involves the blastocyst breaking through the uterine lining and burrowing into the tissue of the uterus. Once implanted, the blastocyst continues to divide and differentiate into the different cell types that will form the embryo and the surrounding tissues needed for development. Implantation is a critical step in the early stages of pregnancy and must occur successfully for a pregnancy to continue. If implantation fails or is disrupted, the blastocyst will not develop properly and will be expelled from the uterus, resulting in a failed pregnancy. It is important to note that implantation is not the same as placentation, which is the formation and development of the placenta, the organ that allows for the exchange of nutrients and waste between the mother and the developing embryo/fetus.

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It is found in moist environment because of its adaptive features.

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Lymph is a fluid that circulates through the lymphatic system, which is part of the immune system. Its main function is to help defend the body against harmful substances, such as viruses and bacteria, by removing waste and debris from tissues and transporting it to the bloodstream for elimination. This makes option "Body defense" the correct answer.