JAMB UTME - Biology - 2019

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.

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.

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.

The movement of blood between the heart and all other parts of the body beside the lungs is

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The movement of blood between the heart and all other parts of the body beside the lungs is called systemic circulation. In the systemic circulation, oxygenated blood flows from the heart to the body's organs and tissues, providing them with the oxygen and nutrients they need to function properly. After the oxygen has been used up by the cells, the blood carrying carbon dioxide and other waste products is then transported back to the heart to be pumped to the lungs, where it will be oxygenated again in the pulmonary circulation. The systemic circulation is a critical part of the body's overall circulatory system, which also includes the pulmonary circulation. Together, these two systems help to ensure that every part of the body has a constant supply of oxygen and nutrients and that waste products are efficiently removed from the body.

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.

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.

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.

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.

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 association between two organisms living together in which only one benefits from the association while the other is neither benefited nor harmed is

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

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.

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 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.

Which of the following pairs of organisms are photosynthetic?

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

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.

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

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

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 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.

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.

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 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.

Which of the following pairs of scientists discovered the Rhesis factor in human blood?

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

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

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

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

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.

In plants, respiration occurs in

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

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 presence of ______ for swimming in a tad-pole enables it to adapt in an aquatic habitat.

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

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.

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.

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 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.

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 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.

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 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

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.