JAMB UTME - Biology - 2019

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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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Good quality food is essential for the proper functioning of the human body. It provides us with the nutrients that we need to stay healthy and strong. However, it is important to note that good quality food cannot provide resistance against malaria. Malaria is a disease that is caused by a parasite that is transmitted through the bite of an infected mosquito. While good nutrition can help support a healthy immune system, it cannot provide specific resistance against malaria. The other functions listed are all important roles that good quality food can perform in the human body. 1. Supplying energy: Food provides us with the energy we need to carry out daily activities, from walking and talking to more strenuous activities like exercising or playing sports. 2. Maintaining health: Eating a balanced diet that includes a variety of nutrient-rich foods helps to maintain good health. Nutrients like vitamins, minerals, and antioxidants are important for proper bodily function and can help prevent chronic diseases. 3. Sustaining growth: Children and teenagers require a balanced diet to support their growth and development. A diet rich in nutrients like protein, calcium, and iron is essential for building strong bones, muscles, and other tissues. In summary, good quality food is important for supplying energy, maintaining health, and sustaining growth. However, it cannot provide specific resistance against malaria or other infectious diseases.

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Secreting irritating fluid is a behavioural adaptation that keep/protects preys from predators.

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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 appendix is considered to be vestigial in humans but functional in other mammals. In humans, the appendix serves no known purpose and can become inflamed and cause pain (appendicitis), which often requires surgical removal. However, in other mammals such as cows and horses, the appendix serves as a fermentation chamber where beneficial bacteria can break down tough plant fibers into simpler sugars that can be easily absorbed. This process is important for their digestion and survival.

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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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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.

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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 statement that describes the autonomic nervous system is "It affects glands, cardiac muscles, and smooth muscles." The autonomic nervous system is a branch of the nervous system that regulates involuntary body functions, such as heart rate, digestion, and breathing. It is composed of two subdivisions: the sympathetic and parasympathetic nervous systems. The autonomic nervous system is responsible for regulating the activity of glands, such as sweat and salivary glands, as well as the contraction of cardiac and smooth muscles, which are found in the walls of organs and blood vessels. These activities are not under conscious control and are regulated by the autonomic nervous system in response to changes in the environment, such as stress or changes in temperature. In contrast, voluntary activities, such as moving our limbs or speaking, are controlled by the somatic nervous system, which is another branch of the nervous system.

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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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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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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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Ecology is best defined as the study of the inter-relationship between living organisms and the environment. It is the study of how organisms interact with each other and their surroundings, including both living and non-living components of the environment. Ecology is a broad field that encompasses many different areas of study, including the study of populations, communities, ecosystems, and biomes. Ecologists examine the ways in which living organisms interact with each other and with their physical and chemical environment, as well as the ways in which human activities can impact these interactions. By understanding the relationships between organisms and their environment, ecologists can develop strategies for conservation, management, and restoration of ecosystems. For example, ecologists can study the impacts of climate change on ecosystems, and develop plans to mitigate these impacts and help protect the biodiversity of our planet. So, the correct answer is "the inter-relationship between living organisms and the environment."

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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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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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The basis of growth involves the following processes except cell reduction. Growth in living organisms is the result of an increase in the size and number of cells. This is achieved through processes such as cell division, cell enlargement, and cell differentiation. Cell division involves the replication of DNA and the separation of the replicated chromosomes into two identical daughter cells. This leads to an increase in the number of cells in an organism. Cell enlargement involves an increase in the size of individual cells due to an increase in the amount of cytoplasm and organelles. This leads to an increase in the overall size of an organism. Cell differentiation is the process by which cells become specialized and take on specific functions within an organism. Cell reduction, on the other hand, involves a decrease in the size or number of cells, and is not a part of the basis of growth. Instead, cell reduction is a process that is associated with aging, disease, and other factors that can lead to a decrease in the size or number of cells in an organism.

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The food supply will have the least effect on the rate of change of the numbers in a population. While food supply can impact the growth and survival of a population, it is less likely to cause rapid changes in population size compared to other factors such as disease, predation, and mutation. Disease, predation, and mutation can all have significant impacts on a population by affecting the survival and reproductive success of individuals, leading to changes in the overall population size. For example, a disease outbreak can reduce the number of individuals in a population, while predation can limit the growth of a population by preying on individuals. Mutations can also impact the population by changing the genetic makeup of the population and altering its ability to survive and reproduce. In conclusion, while food supply is important for maintaining a stable population, it is less likely to cause rapid changes in population size compared to other factors such as disease, predation, and mutation.

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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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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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The correct pair of photosynthetic organisms from the options provided are Euglena and Chlamydomonas. Both Euglena and Chlamydomonas are unicellular organisms that are capable of performing photosynthesis, which is the process of converting light energy into chemical energy. They have chloroplasts, the specialized organelles that carry out photosynthesis, and are therefore capable of producing their own food. On the other hand, Amoeba and Paramecium are heterotrophic organisms, meaning they obtain their food by consuming other organisms. Volvox is a colonial organism, which is also photosynthetic, but it is made up of many cells working together. Rhizopus is a type of fungus that obtains its nutrition through the absorption of organic material. Nostoc is a type of cyanobacteria that is capable of photosynthesis, while Plasmodium is a parasitic organism that causes malaria in humans and is not photosynthetic. So, the correct answer is "Euglena and Chlamydomonas".

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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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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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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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The possession of chloroplast in Euglena viridis enables it to carry out photosynthesis. Photosynthesis is the process by which green plants and algae use sunlight to synthesize food (glucose) from carbon dioxide and water. Chloroplasts are organelles found in the cells of green plants and algae that contain the pigment chlorophyll, which absorbs sunlight and is essential for photosynthesis. Euglena viridis is a unicellular organism that possesses chloroplasts, which enables it to harness sunlight to produce its own food through photosynthesis. Therefore, the answer is that the possession of chloroplast in Euglena viridis enables it to carry out photosynthesis.

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The tilapia fish can be classified under chordata phylum in the animal kingdom.

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

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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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Halophiles are organisms that thrive in high salt concentrations. The adaptations of halophile organisms to their environment are:
(a) The integrity of non-halophile macromolecules is compromised, and the flow of water out of the cell produces a Turgor effect. • (b) Moderate halophiles maintain their structures via the synthesis of compatible organic solutes. • (c) Extreme halophiles maintain their structures via equilibration of cellular and environmental salt concentrations.

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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 main organic molecule present in the nucleus is DNA (Deoxyribonucleic Acid). DNA is the genetic material that contains the instructions for the development, function, growth, and reproduction of all living things. It is a long, double-stranded molecule that is organized into structures called chromosomes. The information in DNA is encoded in a sequence of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), and thymine (T). This sequence determines the genetic code and controls the expression of genes, which are the functional units of heredity. In addition to DNA, the nucleus also contains other organic molecules, such as RNA (Ribonucleic Acid) and proteins, which play important roles in the regulation and expression of genetic information. However, DNA is the central and most critical molecule in the nucleus, as it carries the blueprint for life.

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The part labeled III in the diagram is Hyphae. Hyphae are thread-like structures that form the main body of a fungus. They grow in a network called mycelium, which is made up of many hyphae. Hyphae are responsible for absorbing nutrients and water from the environment and transporting them to the rest of the fungus. They also play a role in the reproduction of the fungus by producing spores. Hyphae can vary in size and shape, but they are typically very thin and can grow very long, allowing the fungus to spread over a large area.

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The structure that controls the activities of the living cell is the nucleus. The nucleus is a membrane-bound organelle that contains the genetic material (DNA) of the cell. It serves as the control center for the cell, directing all of its activities by regulating the expression of genes. The DNA in the nucleus provides the instructions for making proteins, which are the building blocks of the cell and carry out various functions in the body. The nucleus also plays a critical role in cell division, which is the process by which new cells are formed. During cell division, the DNA in the nucleus is replicated and then distributed to the daughter cells, ensuring that they each receive a complete set of genetic material. In summary, the nucleus is responsible for regulating gene expression and directing all of the activities of the cell. It is the structure that controls the fundamental processes of life, making it a vital organelle in all living 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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The process involved during expiration in humans that is not accurate is "The thoracic cavity first increases in volume." During expiration, the diaphragm, which is a muscle located at the bottom of the thoracic cavity, relaxes and moves upwards, decreasing the volume of the thoracic cavity. At the same time, the intercostal muscles, located between the ribs, also relax, and the ribs move downward and inward, causing the chest to decrease in size. Additionally, the sternum moves outward, not inward, during expiration. These combined actions increase the pressure within the thoracic cavity, forcing air out of the lungs. Overall, expiration is a passive process that does not require the use of energy, and it is the opposite of inspiration, which is the process of taking air into the lungs.

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The components of glomerular filtrate are water, electrolytes (such as salts), small organic molecules (such as glucose and amino acids), and waste products (such as urea). Glomerular filtrate is formed in the kidneys and is the fluid that is filtered from the blood in the glomerulus, a network of tiny blood vessels in the kidney. The filtrate contains all the components of blood except for plasma proteins and red and white blood cells. In other words, glomerular filtrate is the fluid that is filtered from the blood and contains all the components of the blood except for large proteins and cells. It is an important step in the process of urine formation, as the filtrate travels through the renal tubules, where it is further modified and waste products are removed to form urine.

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A virus is often considered a living organism because it can reproduce inside living cells. This means that it uses the machinery of the host cell to make copies of itself. However, viruses do not have the ability to carry out all the processes of life, such as producing energy and growing on their own. They rely on the host cell to perform these functions for them. So, whether a virus is considered living or not is still a matter of debate among scientists.

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The sum total of adaptive changes from pre-existing forms that have taken place over a long time resulting in diversity of forms, structures, and functions among organisms is referred to as Evolution. This process of organic evolution involves changes in the genetic makeup of populations of organisms over time, resulting in new species that are better adapted to their environment. These changes occur due to natural selection, genetic drift, mutation, and gene flow, and can lead to the development of diverse forms, structures, and functions among organisms. , Specification, is not a term used in evolutionary biology. Inorganic Evolution, is not a recognized term in biology, as evolution only applies to living organisms. Evolution, is the correct answer, but to be more specific, the full term is Organic Evolution. Organic Evolution, is also a correct answer that specifically refers to the evolution of living organisms.

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Animals are said to be gregarious when they are of the same species and move together in a group. This behavior can be seen in various animals, such as wildebeests, zebras, and birds. There are different reasons why animals may exhibit gregarious behavior. One reason is for protection from predators. Being in a group makes it more difficult for a predator to target one individual. Animals in a group can also help defend against predators by displaying protective behaviors, such as giving an alarm to alert others when danger threatens. Another reason for gregarious behavior is for mating purposes. Some animals may form groups during breeding season, where males compete for females and display their dominance. So, the correct answer is "they are of the same species moving together in a group."

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Vegetable contains mineral salts like magnesium, copper etc which is very essential for body growth.

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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.