JAMB UTME - Biology - 2019

Which of the following is an example of continous variation?

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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.

In an ecosystem, the organism which changes light energy into stored chemical energy is the

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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.

In the theory of use and disuse Lamarck proposed that evolution occurred because of the following except

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The theory of use and disuse proposed by Lamarck stated that evolution occurs because of changes in an organism's environment, which causes an organism to develop specialised characters. These characters are then passed down to offspring, who will have a greater chance of survival because of their increased adaptation to the environment. However, Lamarck's theory was incorrect in one key aspect: he believed that these changes were acquired during an organism's lifetime and then passed down to offspring through inheritance. We now know that traits are not acquired during an organism's lifetime and passed down to offspring, but are instead inherited through genes. This is known as the theory of natural selection, which states that evolution occurs through the survival and reproduction of the fittest individuals with beneficial traits, rather than through the inheritance of acquired characteristics.

Plants which can survive in extremely dry places are called

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The plants which can survive in extremely dry places are called xerophytes. Xerophytes have special adaptations that allow them to conserve water and survive in arid or desert environments where water is scarce. These adaptations include things like thick, waxy leaves to reduce water loss through evaporation, deep root systems to reach water deep underground, and small, spiky leaves to reduce surface area and water loss. Examples of xerophytes include cacti, succulents, and some types of grasses.

Reading the verdict of a case by a magistrate is an example of

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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.

Which of the following is a nitrifying bacterium?

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A nitrifying bacterium is a type of bacterium that is capable of converting nitrogen compounds from one form to another. Out of the options you provided, the correct nitrifying bacterium is Nitrobacter. Nitrobacter is a genus of bacteria that oxidizes nitrite (NO2-) to nitrate (NO3-). This process is called nitrification and is an important part of the nitrogen cycle in the environment.

The specific portion of a habitat which is occupied by a particular species is referred to as

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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.

Which of the following structures controls the activities of the living cell?

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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.

A virus can sometimes be regarded as a living organism because it

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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.

Viruses are pathogens of the following diseases except

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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.

Thunderstorm can be beneficial to plants because it

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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.

The part labeled III in the above diagram is

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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.

Trees in Savanna habitats usually have thick bark which mainly.

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Rate of transpiration is reduced in savannah forest due to thick barks of the trees in savannah forest.

Which of the following is the effect of using artificial pollination in plant breeding?

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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.

Inheritable character/features possessed by an organism can be referred to as

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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.

The study which involves the inter-relationship between groups of organisms or species of organisms living together in an area is

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The study which involves the inter-relationship between groups of organisms or species of organisms living together in an area is called synecology. Synecology is a branch of ecology that examines the interactions and relationships between different species in a given ecosystem or community. It considers the biotic and abiotic factors that affect the survival and growth of populations and how they interact with one another. This study helps us to understand the complex network of relationships between different species and how they are dependent on one another for their survival. It is important for understanding the dynamics of ecosystems and how they may change over time due to human or natural factors.

One important characteristics of green plant is that they

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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.

Which of the following essential substance is contained in vegetable?

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

The above organism can be classified under which phylum in the animal kingdom

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

Which of the following type of soil has the highest water retaining capacity?

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Among the options listed, clay has the highest water retaining capacity. This is because clay particles are very small and have a large surface area, allowing them to attract and hold onto water molecules tightly through a process called adsorption. Additionally, the spaces between the clay particles are very small, which creates a high capillary action that further helps the clay to retain water. In contrast, sand particles are much larger and have a lower surface area, which means that water molecules are less likely to adhere to them. Sand also has larger spaces between its particles, which results in a lower capillary action and less water retention. Loam and laterite fall somewhere in between clay and sand in terms of their water retention capabilities, depending on their specific composition.

One of the following is a process of transmission of hereditary characteristics by chromosomes

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

Which of the following will have the least effect on the rate of change of the numbers in a population

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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.

Which of the blood corpusles are irregular and amoeloid in shape

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The irregular and amoeboid-shaped blood corpuscles are called "Leucocytes," which are also known as white blood cells. Leucocytes are an essential part of our immune system, and their main function is to protect the body against infections, diseases, and foreign invaders. Unlike erythrocytes (red blood cells) and thrombocytes (platelets), which have a uniform, round shape, leucocytes are irregular and amoeboid in shape, allowing them to move freely throughout the body and easily pass through the walls of blood vessels to reach the site of infection or injury. Leucocytes are classified into two main types: granulocytes and agranulocytes, based on the presence or absence of granules in their cytoplasm. Granulocytes have granules in their cytoplasm and include neutrophils, eosinophils, and basophils, while agranulocytes lack granules and include lymphocytes and monocytes. Overall, leucocytes play a critical role in our immune system and help keep us healthy by identifying and fighting off pathogens and foreign invaders.

The attachment of the embryo to the wall of the uterus is called

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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.

Which of the following are components of glomerular filtrate?

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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.

Ecology is best defined as the study of

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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."

The organism above can be found in

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

The glomerular filtrate contains the following except

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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.

The number of times an organism occurs within a given area of a habitat is referred to as

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Population frequency refers to the number of times an organism occurs within a given area of a habitat

The period of inactivity seen in some animals during long period of heat or drought is

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The period of inactivity seen in some animals during long periods of heat or drought is called aestivation. Aestivation is a type of dormancy, similar to hibernation, but it occurs in response to hot or dry conditions, while hibernation occurs in response to cold or food scarcity. During aestivation, animals reduce their metabolic activity and enter a state of deep sleep to conserve energy and water until more favorable conditions return. This strategy helps them survive harsh environmental conditions and avoid dehydration, which can be deadly in hot and dry environments. Some animals that undergo aestivation include certain snails, frogs, and turtles, as well as some mammals like the marsupial mouse and the fat-tailed dwarf lemur.

Which of the following statement is correct about Southern Guinea Savanna in Nigeria

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Southern Guinea Savanna is the largest of all biotic community in Nigeria found in Oyo, Osun, Ekiti Status etc.

The sum total of adaptive changes from pre-existing form that have taken place over a long time resulting in diversity of forms, structures and functions among organism is referred to as

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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.

The possession of chloroplast in Euglena virids enables it to

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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.

Which of the following is a behavioural adaptation that protects prey from predators?

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

The basis of growth involves the following processes except

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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.

Which of the following factors is not considered in a terrestial habitat?

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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.

The type of nutrition in which two organisms of different species live together and derive nutrients from each other is

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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".

Which of the following statement about the similarities in plant and animal transport is correct?

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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.

Which organ removes the largest quantity of water from the blood?

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The organ that removes the largest quantity of water from the blood is the kidney. The kidney is a vital organ in the body that helps filter waste products and excess water from the blood, which are then eliminated from the body as urine. When blood enters the kidney, it passes through tiny blood vessels called capillaries. These capillaries are surrounded by small structures called nephrons, which are responsible for filtering the blood. As blood flows through the nephrons, excess water and waste products are filtered out and collected as urine. The kidneys play an important role in maintaining the body's water balance. They can adjust the amount of water that is excreted from the body depending on how much water is consumed, how much is lost through sweating, and other factors. This helps to maintain the body's fluid levels within a narrow range, which is important for proper bodily function. While the skin and lungs also play a role in removing water from the body, they are not as efficient as the kidneys. The skin eliminates water through sweat, but this process is limited by factors such as humidity and temperature. The lungs eliminate water through exhalation, but this is a small amount compared to the amount eliminated by the kidneys. Overall, the kidneys are the most important organ for removing excess water from the body, and play a critical role in maintaining proper bodily function.

Only specially adapted micro-organisms are found in

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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.