JAMB UTME - Biology - 2019

Which of the following substances pass through the root cell membrane by osmosis?

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Water passes through the root cell membrane by osmosis. Osmosis is the movement of water molecules from an area of higher concentration to an area of lower concentration across a semi-permeable membrane. In plants, water is absorbed through the root hairs of the plant and moves into the root cells. The root cell membrane is selectively permeable, meaning that it allows certain molecules to pass through while blocking others. Water molecules are small enough to pass through the membrane, but larger molecules like cell sap, carbon dioxide, and oxygen cannot pass through by osmosis. Therefore, the correct answer is water.

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 is not a transmitable character in plants

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Haemophilia is not a transmittable character in plants. Haemophilia is a genetic disorder that affects blood clotting in humans and other animals, and it has no relevance to plants. On the other hand, the habit of growth, resistance to environmental factors, and lifespan are all heritable traits that can be transmitted from parent plants to their offspring through genetic material such as DNA. The habit of growth refers to the overall shape and size of the plant, including whether it is a tree, shrub, or herb. Resistance to environmental factors refers to a plant's ability to survive in adverse conditions such as drought, high salinity, or extreme temperatures. Lifespan refers to the length of time that a plant can live and reproduce. All of these traits are important for plant survival and are determined by genetic factors that can be passed down from one generation to the next.

In natural selection, Darwin proposed that evolution occurred because of the following conditions except

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The exception to Darwin's proposed conditions for natural selection is "food and other needs are abundant." In Darwin's theory of evolution by natural selection, he proposed that nature selects those organisms that are best adapted to their environment, and those that are not well-adapted will not survive and reproduce. This selection process occurs because resources such as food and other necessities are limited, and only those that are able to obtain these resources will survive and reproduce. If resources were abundant, there would be no need for competition, and selection would not occur.

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.

The part labelled a in the above diagram is used for

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

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.

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 describes an autonomic nervous system

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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.

Which of the following organs can be considered vestigial in humans but functional in other mammals

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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.

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.

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.

The organic molecule(s) present in the nucleus is/are

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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.

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.

Good quality food will perform the following functions in human except

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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.

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.

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.

Raw materials required by green plants to manufacture their food are

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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.

Which of the following juices contains the enzyme ptyalin?

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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.

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.

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 focuses on the interactions between different species in a community and how they affect each other and the environment. This includes studying how species compete for resources, how they coexist and adapt to changing conditions, and how they play different roles in the ecosystem. Synecology is essential for understanding the functioning and dynamics of ecosystems, and for developing strategies to conserve and manage biodiversity.

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.

The study of an individual organism or a single species of organism and its environment is

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

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 type of nutrition shown by spirogyra is

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The type of nutrition shown by Spirogyra is holophytic. Holophytic nutrition, also known as autotrophic nutrition, is a type of nutrition where an organism synthesizes its own food from inorganic substances, such as carbon dioxide and water, using energy from the sun through the process of photosynthesis. Spirogyra is a type of filamentous green algae that belongs to the group of plants that can carry out photosynthesis to produce their own food. These plants contain chloroplasts, which are specialized organelles that contain chlorophyll, the pigment that absorbs light energy from the sun. During photosynthesis, Spirogyra takes in carbon dioxide and water and uses energy from sunlight to produce glucose and oxygen. This process is essential for the growth and survival of Spirogyra and other autotrophic organisms.

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.

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.

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 organs can be considered vestigial in humans but functional in other mammals

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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.

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.

The male sex cells also called gametes are produced in the testes by a process called

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The male sex cells, also called gametes, are produced in the testes by a process called Spermatogenesis. Spermatogenesis is the process by which sperm cells are produced and mature. It begins in puberty and continues throughout a man's life. During spermatogenesis, the cells in the testes divide and differentiate into sperm cells, which are then stored in the epididymis until they are ready to be ejaculated. Sperm cells are important for fertilization and are necessary for sexual reproduction.

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.

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

What type of vertebrate assists in breathing alongside with the ribs?

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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.

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 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.

A population is best described as

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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.

Albinism is an expression of trait controlled by

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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.

Rabbits cannot survive in an aquatic habitat because they have

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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.

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.