JAMB UTME - Biology - 2018

Which is an animal without red blood cells?

Détails de la réponse

While humans and many other species have red blood, due to the iron in their hemoglobin, other animals have different colored blood. Spiders (as well as horseshoe crabs and certain other arthropods) have blue blood due to the presence of copper-based hemocyanin in their blood. Some animals, such as the sea cucumbers, even have yellow blood. What could make blood yellow? The yellow coloration is due to a high concentration of the yellow vanadium-based pigment, vanabin. Unlike hemoglobin and hemocyanin, vanabin does not seem to be involved in oxygen transport.

The yellowish colored liquid component of blood that normally holds the blood cells in suspension is

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Blood plasma is a yellowish liquid component of blood that normally holds the blood cells in whole blood in suspension. In other words, it is the liquid part of the blood that carries cells and proteins throughout the body. It makes up about 55% of the body's total blood volume.

The greatest amount of energy would be obtained by the Oxidation of 100kg of

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To determine which of the given food items provides the greatest amount of energy upon oxidation, we need to compare their caloric content. Here's a general overview of the approximate caloric values per 100 grams for each type of food:

• Meat: Approximately 250 calories (varies depending on the type and cut of meat)
• Butter: Approximately 717 calories
• Sugar: Approximately 387 calories
• Biscuits: Approximately 450 calories (varies depending on ingredients and recipe)

Now, let's scale these values up to 100 kg (100,000 grams):

• Meat: $\mathrm{<span\; style="font-family:\; Ubuntu;">250</span>}\text{<span style="font-family: Ubuntu;">\hspace{0.17em}</span>}\text{<span style="font-family: Ubuntu;">calories/100g</span>}<span\; style="font-family:\; Ubuntu;">\times </span>\mathrm{<span\; style="font-family:\; Ubuntu;">1000</span>}<span\; style="font-family:\; Ubuntu;">=</span>\mathrm{<span\; style="font-family:\; Ubuntu;">250</span>}<span\; style="font-family:\; Ubuntu;">,</span>\mathrm{<span\; style="font-family:\; Ubuntu;">000</span>}\text{<span style="font-family: Ubuntu;">\hspace{0.17em}</span>}\text{<span style="font-family: Ubuntu;">calories</span>}$250 \, \text{calories/100g} \times 1000 = 250,000 \, \text{calories}
• Butter: $717\text{calories/100g}\times 1000=717,000\text{calories}717\; \backslash ,\; \backslash text\{calories/100g\}\; \backslash times\; 1000\; =\; 717,000\; \backslash ,\; \backslash text\{calories\}$
• Sugar: $387\text{calories/100g}\times 1000=387,000\text{calories}387\; \backslash ,\; \backslash text\{calories/100g\}\; \backslash times\; 1000\; =\; 387,000\; \backslash ,\; \backslash text\{calories\}$
• Biscuits: $450\text{calories/100g}\times 1000=450,000\text{calories}450\; \backslash ,\; \backslash text\{calories/100g\}\; \backslash times\; 1000\; =\; 450,000\; \backslash ,\; \backslash text\{calories\}$

From these calculations, butter has the highest caloric content per 100 kg. Therefore, the greatest amount of energy will be obtained by the oxidation of 100 kg of:

B. butter

A plant tissue that carries water and mineral salt is

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The plant tissue that carries water and mineral salts from the roots to other parts of the plant is called xylem. Xylem is like a pipeline that runs throughout the plant and is responsible for transporting water and dissolved nutrients from the roots to the leaves and other parts of the plant. This tissue is made up of specialized cells called tracheids and vessel elements that are arranged end to end to form long, hollow tubes. These tubes allow water to flow through them with minimal resistance, and the water is pulled up through the xylem by a process called transpiration. In summary, xylem is the tissue responsible for carrying water and mineral salts from the roots to the rest of the plant, and it does so through a network of specialized cells that form long, hollow tubes.

Use the diagram to answer the question. The diagram shows that the organisms are

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The overall reaction in glycolysis can be summarised as

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Use the diagram shown to answer the question. The experiment above is used to demonstrate the process of

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The experiment shown in the diagram is used to demonstrate the process of osmosis. Osmosis is the movement of water molecules across a selectively permeable membrane from an area of high water concentration to an area of low water concentration. In the experiment, the selectively permeable membrane is the potato cell membrane, and the water moves from the area of high concentration (in the beaker) to the area of low concentration (inside the potato). This causes the potato to swell and become heavier as it absorbs the water through osmosis. Thus, the experiment demonstrates the process of osmosis.

Cold blooded animals are referred to as

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Cold-blooded animals are referred to as "poikilothermic". Poikilothermic animals are also known as "ectothermic" animals, which means that their body temperature is regulated by the environment around them. This is in contrast to "homoeothermic" animals, also known as "endothermic" animals, which can regulate their own body temperature internally. Examples of poikilothermic animals include reptiles, amphibians, and most fish. These animals are often seen basking in the sun to warm up or seeking out cooler places in order to lower their body temperature. They are able to function at a range of different temperatures, but their bodily functions are often slower at cooler temperatures. On the other hand, homoeothermic animals, such as mammals and birds, are able to maintain a stable internal body temperature, even when the temperature of their environment fluctuates. This allows them to function effectively in a wider range of environmental conditions.

A group of closely related organisms capable of interbreeding to produce the fertile offspring are known as members of a

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The correct answer is "species". Species are a group of living organisms that share common characteristics and can interbreed to produce fertile offspring. This means that members of the same species can mate and produce offspring that can themselves reproduce, while organisms from different species cannot produce fertile offspring together. For example, dogs can breed with other dogs to produce fertile puppies, but they cannot breed with cats to produce offspring that can reproduce. Therefore, dogs and cats belong to different species.

The energy released by 1 gram of glucose is

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The energy released by 1 gram of glucose is about 4 kcal. To put it simply, when our bodies break down glucose, a type of sugar that is a source of energy, it releases energy that we can use. This energy is measured in units of calories, and 1 kilocalorie (kcal) is equivalent to 1,000 calories. So, when 1 gram of glucose is broken down, it releases approximately 4 kcal of energy.

Double fertilisation is a unique features of

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Double fertilization is a unique feature of angiosperms, also known as flowering plants. During double fertilization, two sperm cells from the pollen grain fertilize two different cells in the female reproductive structure of the flower. One sperm cell fertilizes the egg cell to form the zygote, which will develop into the embryo of the seed. The other sperm cell fertilizes two nuclei in the central cell, which results in the formation of a triploid cell called the endosperm. The endosperm provides nourishment to the developing embryo. This process is unique to angiosperms and is not seen in bryophytes, pteridophytes, or algae. It is one of the key factors that has contributed to the success of angiosperms, as the endosperm provides a rich source of nutrients for the developing embryo, giving it a competitive advantage for survival and growth.

The longest bone in the body is the

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The longest bone in the body is the femur. The femur is located in the thigh region and runs from the hip joint to the knee joint. It is also the strongest bone in the body, designed to support the weight of the body and withstand the forces produced by activities such as running and jumping. The femur's length can vary depending on a person's height, with taller people generally having longer femurs. Overall, the femur plays a critical role in allowing us to walk, run, and engage in other physical activities.

The vessel carrying oxygenated blood to the tissues is

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The vessel carrying oxygenated blood to the tissues is called an artery. Arteries are blood vessels that carry blood away from the heart, and they have thick, muscular walls that can withstand the high pressure of blood being pumped by the heart. The oxygenated blood that is pumped out of the left ventricle of the heart into the aorta is then distributed throughout the body via the network of arteries. Arteries branch into smaller vessels called arterioles and then into even smaller vessels called capillaries, where oxygen and nutrients are delivered to the body's tissues. So, arteries play a crucial role in ensuring that oxygenated blood is delivered to the body's tissues to support their proper functioning.

Which of the following structures is not a skeletal material?

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Bone is the substance that forms the skeleton of the body. It is composed chiefly of calcium phosphate and calcium carbonate. Chitin is a major constituent of the exoskeleton, or external skeleton, of many arthropods such as insects, spiders, and crustaceans. The main structural components of our bodies are bone, muscle, and cartilage. Bones are rigid, while muscles bend, stretch, and are flexible. Cartilage connective tissue is the perfect halfway point between these other tissues. It is not as rigid or as hard as bone, and it is also less flexible than muscle. Therefore, we find cartilage in places where we need some support and structure, but a bit of flexibility as well. This includes places such as our joints, our ears, and our nose, as well as in between the vertebrae in our spinal column.

Which of the following cycles involves the process of precipitation and transpiration?

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The cycle that involves the process of precipitation and transpiration is the water cycle. The water cycle is the process by which water circulates through the Earth's environment. It starts with the evaporation of water from bodies of water, such as oceans, lakes, and rivers, as well as from the soil and plants through a process called transpiration. This water vapor then rises into the atmosphere, where it cools and condenses into clouds. When these clouds become heavy enough, the water falls back to Earth as precipitation, which can take the form of rain, snow, sleet, or hail. Once the precipitation falls to the ground, it can either be absorbed by the soil and become groundwater or run off into bodies of water. From there, the cycle starts again. In summary, the water cycle involves the process of precipitation, which is the falling of water from the atmosphere to the Earth's surface, as well as the process of transpiration, which is the release of water vapor from plants. This cycle is essential for providing fresh water to living things and maintaining the Earth's environment.

Use the diagram shown to answer the question. In plant cells, the role of the membrane is played by the

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The role of the membrane in plant cells is played by the cell wall. The cell wall is a protective outer layer that surrounds the plasma membrane, which is a thin layer that encloses the cytoplasm and other cell structures. The cell wall provides support and structure to the cell, and also helps to maintain the shape of the cell. The nucleolus is a structure within the nucleus of a cell that is involved in the production of ribosomes, while the cytoplasm is the gel-like substance that fills the interior of a cell and contains all of the cell's organelles. The mitochondrion is an organelle within the cytoplasm that is responsible for generating energy for the cell.

Which of the following statements is true about sandy soil?

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Sandy soils are well drained. They have low water holding capacity and are therefore drought prone. They become firm when wet (the opposite of clay), and loose when dry. Sandy soil is light and easy to dig.

An animal which is active during the day is known as a

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An animal that is active during the day is known as a diurnal animal. This means that it is awake and active during the daytime hours, when the sun is shining, and typically sleeps or rests during the night. Diurnal animals have evolved to take advantage of the sunlight and are often adapted to see well in bright light. Examples of diurnal animals include humans, birds, squirrels, and many species of primates.

An accurate identification of a rapist can be carried out by conducting

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An accurate identification of a rapist can be carried out by conducting DNA analysis. DNA analysis involves collecting and analyzing a sample of DNA from a suspect, such as a hair, skin, or semen sample, and comparing it to a sample of DNA taken from the crime scene. If the DNA profiles match, it can provide strong evidence linking the suspect to the crime. Blood group tests and behavioral tests are not reliable methods for identifying a rapist, as they do not provide a unique identifier like DNA analysis does. Additionally, RNA analysis is not typically used for the identification of rapists. DNA analysis is the most scientifically accepted and accurate method for identifying individuals in criminal investigations, including sexual assault cases.

What is the function of trichocyst in paramecium?

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Trichocyst, a structure in the cortex of certain ciliate and flagellate protozoans consisting of a cavity and long, thin threads that can be ejected in response to certain stimuli. Trichocysts may be widely distributed over an organism or restricted to certain areas (e.g., tentacles, papillae, around the mouth). It is also a structure in the cortex of certain ciliate and flagellate protozoans consisting of a cavity and long, thin threads that can be ejected in response to certain stimuli.

The damage to ozone layer is caused by

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Ozone sits in the upper atmosphere and absorbs ultraviolet radiaton, another type of solar energy that's harmful to humans, animals and plants. CFCs and halons cause chemical reactions that break down ozone molecules, reducing ozone's ultraviolet radiation-absorbing capacity. Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.

In the egg of a bird, the embryo is located in the

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Special temporary organs or embryonic membranes form within the egg, both to protect the embryo and to provide for its nutrition, respiration, and excretion. These organs include the yolk sac. The yolk sac is also responsible for the initial circulation and is in charge of delivering nutrients, via a primitive aorta, to the developing embryo through a process called vitelline circulation.

Which of the following diseases is not hereditary?

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Scabies is the disease that is not hereditary. Scabies is a skin infestation caused by a tiny mite called Sarcoptes scabiei. It spreads through direct skin-to-skin contact with an infected person. Scabies is not a genetic disorder and does not pass down from parent to child through genes. It is caused by a microscopic organism that can infect anyone who comes into contact with it. On the other hand, Albinism, Haemophilia, and Color blindness are all hereditary diseases. Albinism is a genetic condition that affects the production of melanin, resulting in little or no pigment in the skin, hair, and eyes. Haemophilia is a genetic disorder that affects the blood's ability to clot properly. Color blindness is a genetic condition that affects the ability to distinguish between different colors. In summary, while Scabies is caused by a tiny mite and is not hereditary, Albinism, Haemophilia, and Color blindness are all genetic conditions that are inherited from one's parents.

Use the diagram to answer the question. The breeding posture illustrated in the diagram is known as

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The breeding posture illustrated in the diagram is known as "amplexus". Amplexus is a mating behavior displayed by many amphibians, in which the male grasps the female with his front legs from behind and holds her in position during mating. This position helps the male to fertilize the eggs as they are laid by the female. Amplexus can be further classified into two types: axillary amplexus, in which the male grasps the female's body just behind the front legs, and inguinal amplexus, in which the male grasps the female's body in the pelvic region. This behavior is critical for the reproduction of many amphibian species, and without it, successful fertilization of the eggs would be less likely to occur.

An organism which exhibit extracellular digestion is

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Extracellular digestion is a process in which saprobionts feed by secreting enzymes through the cell membrane onto the food. During extracellular digestion, food is broken down outside the cell either mechanically or with acid by special molecules called enzymes.

Which of the following is a mixed gland?

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A mixed gland is a gland that is both exocrine and endocrine, for example, the pancreas. Pancreas is known as a mixed gland because it performs functions of both exocrine and endocrine glands.

The immediate product of meiosis in flowering plants is the

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Pollen grains form in the two pollen sacs located in the anther. Each pollen sac contains specialized chambers in which the microspore mother cells are enclosed and protected. The microspore mother cells undergo meiosis to form four haploid microspores. Subsequently, mitotic divisions form four pollen grains. Inside each pollen grain is a generative cell; this cell will later divide to produce two sperm cells. Pollen grain shapes are specialized for specific flower species.

Spectacles with convex lenses correct long-sightedness by

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Spectacles with convex lenses correct long-sightedness by converging the light rays before they enter the eye. In long-sightedness, also known as hyperopia, the eyeball is too short, which causes light to focus behind the retina instead of directly on it. This results in blurry vision, especially when looking at close objects. Convex lenses are thicker in the middle and thinner at the edges, and they bend light rays towards each other. When a person with long-sightedness wears spectacles with convex lenses, the lenses converge the light rays before they enter the eye, which compensates for the shortness of the eyeball. This causes the light rays to focus directly on the retina, which results in clearer vision. Therefore, by converging the light rays before they enter the eye, convex lenses correct long-sightedness.

Cytokinesis of mitosis is a process that ensures that

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Cytokinesis is the final stage of mitosis, the process by which a cell divides to form two identical daughter cells. During cytokinesis, the cytoplasm of the original cell is divided into two parts, with each part containing a complete set of genetic material (chromosomes). The main purpose of cytokinesis is to ensure that each daughter cell receives a complete set of genetic material and the necessary organelles to function properly. This is important because if one daughter cell received more genetic material or more organelles than the other, it could lead to problems such as cell death or mutations. Therefore, "each daughter cell gets the necessary organelles" is the correct label to associate with the question above. While the other options may be important aspects of mitosis, they do not directly relate to the role of cytokinesis in ensuring that each daughter cell receives a complete and functional set of genetic material and organelles.

Which of the following groups of organisms has kidney as the excretory organ?

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The group of organisms that have kidneys as the excretory organ is: fishes, amphibians, birds, and man. Kidneys are specialized organs that remove waste products, excess water, and other impurities from the blood. These waste products are then eliminated from the body as urine. Fishes, amphibians, birds, and mammals (including humans) all have kidneys as their primary excretory organ. In fish, the kidneys are responsible for removing excess water and electrolytes from the blood. In amphibians, the kidneys also play a role in maintaining water balance, as well as removing nitrogenous wastes. In birds and mammals, the kidneys are responsible for filtering the blood, regulating water and electrolyte balance, and eliminating waste products. In contrast, annelids (a group of segmented worms), insects, protozoans, reptiles, and tapeworms have different excretory organs. For example, insects have specialized structures called Malpighian tubules that remove waste products and excess water from their blood, while tapeworms excrete waste products through their skin.

Maltose is combination of glucose and

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Maltose is a disaccharide, which means it is made up of two simple sugar molecules. Specifically, maltose is made up of two glucose molecules that are joined together by a type of bond called a glycosidic bond. Glucose is a monosaccharide, which means it is a simple sugar that cannot be broken down into any simpler sugars. Maltose is formed when two glucose molecules are linked together by a glycosidic bond. This bond is formed by the removal of a molecule of water between the two glucose molecules. The resulting molecule of maltose is therefore a combination of two glucose molecules. Sucrose, on the other hand, is a different type of disaccharide that is made up of one glucose molecule and one fructose molecule, while galactose is a monosaccharide that can combine with glucose to form lactose, a disaccharide found in milk. So to summarize, maltose is a disaccharide made up of two glucose molecules that are linked together by a glycosidic bond. It is not made up of fructose, sucrose, or galactose.

The reason why hospitals use saline solutions as drip instead of water is

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Saline, also known as saline solution, is a mixture of sodium chloride in water and has a number of uses in medicine. Intravenous therapy (IV) is a therapy that delivers liquid substances directly into a vein. Saline is used in I.V. therapy, intravenously supplying extra water to rehydrate patients or supplying the daily water and salt needs ("maintenance" needs) of a patient who is unable to take them by mouth. Because infusing a solution of low osmolality can cause problems such as hemolysis, intravenous solutions with reduced saline concentrations typically have dextrose (glucose) added to maintain a safe osmolality while providing less sodium chloride. The amount of normal saline infused depends largely on the needs of the patient (e.g. ongoing diarrhea or heart failure).

The function of pith in plant is

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Pith, or medulla, is a tissue in the stems of vascular plants. Pith is composed of soft, spongy parenchyma cells, which store and transport nutrients throughout the plant. In eudicots, pith is located in the center of the stem. In monocots, it extends also into flowering stems and roots.

Mineral salts can be absorbed into roots by

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In plants and animals, mineral absorption, also called mineral uptake is the way in which minerals enter the cellular material, typically following the same pathway as water. In plants, the entrance portal for mineral uptake is usually through the roots by a process of diffusion and active transport.

An example of a radially symmetrical organisms is

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An example of a radially symmetrical organism is Hydra. Radial symmetry means that an organism has a circular shape and its body parts are arranged around a central axis, like the spokes on a wheel. Hydra is a small, freshwater animal that has a cylindrical body and tentacles that radiate out from its central axis. This type of symmetry allows Hydra to detect and capture prey from all directions. Planaria are also radially symmetrical flatworms, while tapeworms and roundworms are examples of organisms with bilateral symmetry, meaning that they have a distinct front and back and a left and right side.

Examples of animals with mammary glands include the following except

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A mammary gland is an exocrine gland in mammals that produces milk to feed young offspring. Mammals get their name from the Latin word mamma, "breast". Hens do not have mammary glands.

Ozone hole refers to

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Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.

What is the critical limiting factor for plants below the photic zone in an aquatic ecosystem?

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Primary production in the photic zone is influenced by three major factors—nutrients and light, which are essential for photosynthesis, and grazing pressure, the rate at which the plants are eaten by herbivores.

A boy who is fond of swimming in a pond finds himself passing urine with traces of blood. He is likely to have contracted

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The boy who is fond of swimming in a pond and passes urine with traces of blood is likely to have contracted schistosomiasis. Schistosomiasis is a parasitic infection caused by a type of flatworm called Schistosoma that commonly inhabits freshwater snails and bodies of water such as ponds and lakes. When a person comes into contact with water contaminated with the parasite, it can penetrate the skin and enter the bloodstream, where it eventually travels to the bladder or intestines and causes inflammation and damage to the tissues. This can lead to symptoms such as blood in the urine or stool, abdominal pain, diarrhea, and anemia. If left untreated, schistosomiasis can lead to chronic health problems such as liver and kidney damage. Therefore, it is important to seek medical attention if experiencing symptoms after swimming or coming into contact with freshwater bodies in endemic areas.

Study the diagram of a food chain shown and use it to answer the question.

P ---> Q ---> R ---> S ---> T

The organism designated P in the food chain above is normally sustained by energy from

Détails de la réponse

The organism designated P in the food chain is normally sustained by energy from the sun. This is because P is likely at the bottom of the food chain, which means it is a primary producer. Primary producers, such as green plants, use energy from the sun to produce their own food through photosynthesis. This food is then consumed by the next organism in the food chain, which is Q. The energy then passes from one organism to the next, all the way up the food chain to the top predator. Therefore, in this food chain, P is likely a green plant or another type of primary producer that uses energy from the sun to produce its own food, making sunlight the source of energy for P.