JAMB UTME - Biology - 2019

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

Maelezo ya Majibu

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.

Rabbits cannot survive in an aquatic habitat because they have

Maelezo ya Majibu

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.

Trees in Savanna habitats usually have thick bark which mainly.

Maelezo ya Majibu

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

A population is best described as

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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

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

Maelezo ya Majibu

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

Albinism is an expression of trait controlled by

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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

Maelezo ya Majibu

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

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

Maelezo ya Majibu

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 is a behavioural adaptation that protects prey from predators?

Maelezo ya Majibu

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

Which of the following describes an example of fertilization in higher organisms?

Maelezo ya Majibu

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.

One important characteristics of green plant is that they

Maelezo ya Majibu

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 organ removes the largest quantity of water from the blood?

Maelezo ya Majibu

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.

Possession of thin membrane enables a tapeworm to

Maelezo ya Majibu

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

One of the following is an effect of clay soil on vegetation

Maelezo ya Majibu

Clay soil's effect on vegetation is that it supports light vegetation such as forest and luxuriant vegetation.

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

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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.

Which of the reproductive system in mammals secretes a part of the seminal fluid which raises the pH of the fluid in the female reproductive system?

Maelezo ya Majibu

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.

Which of the following are components of glomerular filtrate?

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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 glomerular filtrate contains the following except

Maelezo ya Majibu

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 organism above can be found in

Maelezo ya Majibu

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

The type of nutrition shown by spirogyra is

Maelezo ya Majibu

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 pairs of organisms are photosynthetic?

Maelezo ya Majibu

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".

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

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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 part labeled III in the above diagram is

Maelezo ya Majibu

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.

Raw materials required by green plants to manufacture their food are

Maelezo ya Majibu

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 blood corpusles are irregular and amoeloid in shape

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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.

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

Maelezo ya Majibu

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

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

Maelezo ya Majibu

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

Maelezo ya Majibu

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 following essential substance is contained in vegetable?

Maelezo ya Majibu

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

The change in the genetic make up of an organism resulting in an inheritable characteristics which is new is

Maelezo ya Majibu

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.

One of the following is not the theory of natural selection stated by Charles Dawin

Maelezo ya Majibu

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

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

Maelezo ya Majibu

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.