an animal has the following characteristics: bilateral symmetry, mouth but no anus, ribbon shape. which phylum does the animal belong to?

This process is called synaptic plasticity. Synaptic plasticity is the ability of two neurons to form a stronger connection when they become active at the same time. This process is important for learning, memory formation, and other cognitive processes.

If two brain cells become more active at the same time, the connections between them grow stronger. This process is called Hebbian Learning.The learning process that occurs when the firing of one neuron strengthens the synapse that leads to a neighboring neuron is known as Hebbian learning. It is named after Canadian psychologist Donald Hebb, who first proposed the concept in 1949.

This theory is based on the idea that the two neurons that fire together become connected, and the synaptic link between them grows stronger when they do. Hebbian learning has been related to a variety of learning processes in the brain, including the development of perceptual maps in the visual cortex, the refinement of motor control, and the learning of higher-order cognitive abilities. It is thought to underlie most types of memory and plays a critical role in neural development, memory formation, and learning.

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The tunica media is the structural layer of blood vessels most responsible for maintaining blood pressure. Option C.

It is made up of a layer of smooth muscle cells and elastic connective tissue, which act together to regulate blood flow and pressure. The elastic connective tissue is able to stretch and expand, helping to maintain a constant pressure within the vessel walls.

When the pressure increases within the vessel, the muscle cells contract to restrict the flow, while when the pressure decreases the muscle cells relax to allow more blood flow.

The tunica intima, or innermost layer of the vessel wall, is composed of endothelial cells and helps to protect the vessel from damage. The subendothelial layer lies beneath the endothelial cells and provides a framework for the endothelial cells to attach to. Lastly, the tunica externa is the outermost layer of the vessel wall and helps to provide strength and support.
Together, these three layers of the blood vessel help to maintain consistent blood pressure and ensure the flow of blood throughout the body.

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Option 2. The sphincters' muscle block urine as it sync with urinary bladder muscle

The sphincter muscle is a ring-shaped muscle that surrounds the urethra, the tube that carries urine from the bladder out of the body. There are two sphincter muscles that control the flow of urine: the internal sphincter, which is made up of smooth muscle and is under involuntary control, and the external sphincter, which is made up of skeletal muscle and is under voluntary control.

The sphincter muscle works in coordination with the bladder muscle to control the flow of urine. When the bladder is full, the bladder muscle contracts to expel urine, while the internal sphincter muscle relaxes to allow urine to pass through the urethra. The external sphincter muscle remains contracted to maintain continence.

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A population refers to a group of individuals of the same species living in the same geographic area and potentially interbreeding. Based on this definition "The birds of Guam," is considered a population. Here option A is the correct answer.

The birds of Guam share the same species identity, and they all live in the same geographic area, providing the potential for interbreeding.

In contrast, option B, "All birds and snakes of Hoi Polloi," includes multiple species, and option D, "The arc-crested fruit doves of Hoi Polloi, all brown snakes on Earth," includes only one species of bird and one species of snake, but from different geographic locations.

Option C, "The arc-crested fruit doves of Hoi Polloi," refers to a single species, but it is unclear if all members of that species in the area are included or if they are limited to a specific geographic area.

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Complete question:

Which group is considered a population?

A) The birds of Guam.

B) All birds and snakes of Hoi Polloi.

C) The arc-crested fruit doves of Hoi Polloi.

D) The arc-crested fruit doves of Hoi Polloi, all brown snakes on Earth.

Neurotransmitter activity at a synapse can be terminated by three main mechanisms: reuptake, enzymatic breakdown, and diffusion.

Reuptake is when neurotransmitters are taken back into the presynaptic neuron, while enzymatic breakdown is when enzymes break down neurotransmitters into smaller molecules. Diffusion is when neurotransmitters move away from the synapse, which causes the neurotransmitter concentration to decrease.

Reuptake is a process by which the neurotransmitter is taken back into the presynaptic neuron and broken down, either for reuse or for storage. This process is known as active reuptake and is very efficient in preventing the build-up of neurotransmitters in the synapse.

Enzymatic breakdown is when enzymes break down neurotransmitters into smaller molecules, and this process can occur both within and outside of the synapse.

Finally, diffusion is the process by which neurotransmitters move away from the synapse and the concentration of neurotransmitter decreases over time. This process is known as passive diffusion and is the most common way neurotransmitter activity is terminated at the synapse.

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The statement "A gene is a section of DNA in which the code for a protein is located" best describes a gene.

A gene is a basic unit of heredity in living organisms. It is a specific sequence of DNA nucleotides that contains the instructions for making a functional product, such as a protein or RNA molecule.  

In other words, a gene is a specific sequence of nucleotides within DNA that contains the instructions for making a functional product, such as a protein or RNA molecule.

Genes are responsible for determining the physical and behavioral traits of an organism, such as eye color, height, susceptibility to certain diseases, and many other characteristics.

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Answer:

Owls and Falcons belong to distinct families, each evolving uniquely to suit their distinctive hunting requirements. Specializing in hunting, Falcons rely on speed and agility to catch their prey featuring a streamlined body with long, pointed wings and sharp talons. In contrast, Owls are nocturnal hunters that heavily rely on stealth and silence to capture their prey with the use of forward-facing large eyes and sensitive hearing under low-light conditions. Owls possess flight feathers that are fringed with soft edges enabling them to fly silently. Falcons employ stiff, smooth feathers that promote fast flight. These diverse hunting methodologies have resulted in the animals' unique adaptations and evolutionary diversity.

Explanation:

Mutations can occur with a single nucleotide change. The misfolding of the hemoglobin protein results from amino acid substitution.

A mutation is an alteration in the DNA sequence that results in a modified gene product or a modified regulatory element. A mutation is a permanent alteration to the DNA sequence that makes up a gene.

A mutation can occur in any part of the DNA sequence. A mutation can occur with a single nucleotide change. The misfolding of the hemoglobin protein results from amino acid substitution. Misfolding is a term used to describe the folding of a protein molecule into an incorrect three-dimensional structure.

Misfolding occurs when a protein does not fold correctly into its normal, biologically functional state. Misfolding of proteins is linked to a variety of diseases. Hemoglobin is a protein that is crucial for the transport of oxygen in the body. Hemoglobin is the oxygen-carrying protein in the red blood cells of mammals.

Hemoglobinopathy is a term used to describe diseases caused by mutations in the hemoglobin gene. These illnesses can have a variety of consequences, ranging from minor symptoms to serious, life-threatening illnesses.

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There are also ethical concerns surrounding the use of cord blood as a medical treatment, as some people believe that it is wrong to use stem cells from a baby in this way.

The use of a baby's cord blood to treat a disease at a later date can create a problem as it has several limitations. Some of these limitations include limited availability, high cost, and the need for a perfect match to the HLA of the recipient. Additionally, cord blood stem cells also have a lower stem cell count than bone marrow, which can make it difficult to transplant them into an adult patient. Moreover, there are other ethical concerns related to the use of cord blood as a medical treatment. One problem with using cord blood is that it contains a limited number of stem cells, which makes it less effective than other treatments. Furthermore, the costs associated with collecting, storing, and processing cord blood stem cells are often quite high, which can make it difficult for families to access this treatment option. Additionally, since cord blood stem cells must match the HLA of the recipient, it may be difficult to find a donor who is a perfect match.

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According to the data interpretation, the water uptake by radish plant seeds increases with increasing temperature. This implies that water intake is directly proportional to temperature.

Because of the increased concentration of sunlight and warm air, transpiration will increase as the temperature rises. However, if temperatures remain high for an extended period of time, resulting in drought, transpiration may decrease to conserve water in the plant.

What is transpiration ?

Transpiration is the movement of water through a plant and the evaporation of water from aerial parts such as leaves, stems, and flowers. Water is essential for plants, but only a small portion of the water absorbed by the roots is used for growth and metabolism. Transpiration and guttation account for the remaining 97-99.5%. Leaf surfaces are dotted with pores known as stomata (plural "stoma"), which are more numerous on the undersides of the foliage in most plants. Guard cells and their stomatal accessory cells (collectively known as the stomatal complex) surround the stomata, which open and close the pore. Transpiration occurs through the stomatal apertures and can be thought of as a necessary "cost" associated with opening the stomata to allow air to pass through.

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Humoral immunity involves the production and activity of antibodies, which are proteins produced by B cells (a type of white blood cell) that recognize and bind to specific antigens (foreign substances) on the surface of pathogens such as bacteria, viruses, and fungi.

The antibodies are then able to neutralize or eliminate the pathogens by various mechanisms such as blocking their ability to enter host cells, marking them for destruction by other immune cells, or activating complement proteins to destroy them directly.

There are five major classes (or isotypes) of antibodies that can be produced by B cells, each with a distinct structure and function: IgM: the first antibody produced during an immune response, primarily found in the bloodstream and able to activate complement proteins.

IgG: the most abundant antibody in the bloodstream, able to cross the placenta and provide passive immunity to the developing fetus.

IgA: found in high concentrations in mucosal secretions such as saliva, tears, and breast milk, providing protection against pathogens at the body's entry points.

IgD: found on the surface of B cells and involved in B cell activation.

IgE: involved in allergic reactions and defense against parasites.

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Photorespiration rate is minimized by ensuring that RubisCO always encounters high CO2 concentrations which are accomplished by two pathways: the C₄ pathway and the CAM pathway.

The C₄ pathway involves the formation of an unstable four-carbon acid in the mesophyll cells which is then converted to a three-carbon acid in bundle sheath cells. This process of forming the four-carbon acid is called "C₄ carboxylation" and it allows for the CO₂ to be more concentrated in the bundle sheath cells. This increases the efficiency of RubisCO and reduces the rate of photorespiration.

The CAM pathway involves the opening of the stomata at night when temperatures and light levels are lower. This process allows the plant to take in CO₂ and store it as malic acid until the next day. This process increases the concentration of CO₂ available to Rubisco and reduces the rate of photorespiration.

In conclusion, the two pathways that minimize photorespiration rate by ensuring that RubisCO always encounters high CO₂ concentrations are the C₄ pathway and the CAM pathway.

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The protein that is present in animals is keratin. Keratin is an apomorphy in animals.

An apomorphy is a distinctive and novel characteristic that is present in a species but not in any of its ancestors. An apomorphy is a characteristic that separates one group of organisms from others. The term is utilized in cladistics to indicate a character or feature that defines a group of organisms, but not the ancestor from which they are derived.A keratin is a type of structural protein that is found in animals. Keratin is produced by cells called keratinocytes and is found in the outer layer of skin, hair, nails, and other structures. Keratin plays a critical role in the strength and durability of these structures.In addition to providing structural support, keratin has a variety of other functions.

For example, keratin in the hair shaft helps to prevent water loss and provides a barrier against harmful environmental factors. In nails, keratin helps to protect the underlying tissue from damage.

Therefore, it can be concluded that the presence of keratin is an apomorphy of animals.

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The interior structure of a cell is observed to move when viewed under a microscope. The cytoskeleton, which causes cytoplasmic streaming, is what causes this movement in the interior skeletal-like component.

The two most common methods for seeing living cells are phase-contrast microscopy and differential interference-contrast microscopy. The cell, which Robert Hooke first discovered in 1665, has a long and fascinating history that has ultimately led to many of today's scientific breakthroughs.

The cell membrane, the nucleus, and the cytoplasm make up a cell's three components. The cytoplasm contains hundreds or perhaps thousands of tiny, distinct structures known as organelles, as well as intricate arrangements of microscopic fibers.

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Answer: The structures indicated by the arrows in the picture that have pinched off the Golgi apparatus and will deliver their contents to another part of the cell are called transport vesicles.

What is the Golgi apparatus?

The Golgi apparatus is a stack of flattened vesicles and sacs, commonly known as a stack of pancakes, that serves as a central processing station for cellular proteins and lipids.

The proteins and lipids are primarily obtained from the endoplasmic reticulum (ER) and later dispersed to their destination sites within the cell. The Golgi body accepts proteins and lipids from the rough ER, processes them into a functional form, and then dispatches them to the right place in the cell.

It is the transport vesicles that carry the processed proteins and lipids from the Golgi body to the correct location. After it arrives at its destination, the vesicle merges with the membrane and discharges its contents.



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The statement "In type 2 diabetes, the body's cells do not respond adequately to the hormone insulin" is true because when the cells don't respond, the body cannot adequately use the glucose from the bloodstream for energy, resulting in high blood sugar levels.

When the cells don't respond, the body cannot adequately use the glucose from the bloodstream for energy, resulting in high blood sugar levels. Insulin helps regulate blood sugar levels by allowing glucose from the bloodstream to enter the body's cells for energy.Type 2 diabetes is caused by a combination of factors, including genetics and lifestyle.

Being overweight or obese, having a sedentary lifestyle, and consuming a diet high in processed foods and sugar are all risk factors. Treatment for type 2 diabetes typically involves making lifestyle changes such as exercising more and eating a healthy diet, as well as taking medications or insulin if needed.

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The first hypothesis suggests that the genetic divergence between the populations of the lizard species may have been facilitated by physical isolation. According to this hypothesis, the lizards may have become genetically and phenotypically different as a result of geographic isolation. The lizards may have been physically separated on these islands, either by natural barriers such as water bodies or by human activities such as farming or logging, for long periods of time.

The second hypothesis suggests that the genetic divergence between the populations of the lizard species may have been facilitated by different selection pressures. According to this hypothesis, the lizards may have become genetically and phenotypically different as a result of different environmental pressures on different islands. This hypothesis suggests that the lizards may have adapted differently to the different environments of different islands.

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Early weight gain is mainly due to bone growth, muscle growth, and internal organ growth. An increase in fat cells also contributes to weight gain, but it happens later in the development process.

The early weight gain of an infant is mainly due to the growth of bones, muscles, and internal organs. Bone growth accounts for about half of the weight gained by infants in the first few months of life. Muscle growth also contributes significantly to early weight gain. Internal organ growth, particularly the growth of the brain, accounts for the remainder of the weight gain. An increase in fat is also a contributing factor, but it generally happens later in the development process.


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The dyes used in gel electrophoresis are usually negatively charged because they move towards the positive electrode. The positively charged particles are attracted to the negative electrode. Hence, it can be inferred that the dyes tested were negatively charged in gel electrophoresis.

In the gel electrophoresis apparatus, the dyes are tested positively or negatively charged. It is known that the apparatus creates an electrical field with positive and negative poles at each end. The charged particles are separated based on the strength of the charge they possess.

The gel electrophoresis is a technique that helps in the separation of DNA or RNA molecules based on their size and charge. The samples are loaded into a well that is created in a gel and exposed to an electric field.

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The correct option is B. Genetic drift

Genetic drift is a random process in which certain genetic traits become more or less common in a population over time due to chance events. This can happen when a small group of individuals (a founder population) becomes isolated from the rest of the population, and passes on its genetic traits to their offspring.

Genetic drift can also occur when a population experiences a natural disaster, an epidemic or a population bottleneck, which leads to the death of a large number of individuals.

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A high-carbohydrate diet for athletes can result in increased secretion of insulin, increased use of fat for fuel, and storage of glycogen in muscles and liver.

Increased secretion of insulin happens when carbohydrates are consumed as the body releases insulin into the bloodstream to help convert carbohydrates into energy. The body also begins to use more fat for fuel instead of carbohydrates as the primary energy source. This results in increased fat burning for energy. Finally, the carbohydrates are stored in the muscles and liver as glycogen, which is a form of stored energy used during exercise.

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The thick filament is composed of the myosin molecule. Pivoting the head of this molecule provides what is known as the power stroke. The thick filament is a component of the sarcomere, which is the basic unit of contraction in skeletal muscle.

The thick filament, which is made up of myosin molecules, is responsible for generating the force of muscle contraction.  

Myosin is a protein that makes up the thick filaments of muscle fibers. The molecule consists of two main regions: the head region and the tail region.

The tail region of each myosin molecule is responsible for binding to other myosin molecules in order to create the thick filament.

The head region of the myosin molecule is responsible for binding to and interacting with the thin filament during the process of muscle contraction.

When the myosin head binds to the thin filament, it undergoes a conformational change that results in the power stroke. This power stroke is what causes the thick filament to slide past the thin filament, generating the force of muscle contraction.

Overall, the thick filament and the myosin molecules that make it up are essential for muscle function and movement.

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If a mutation stops the ability for pepsinogen to respond to the presence of pepsin, pepsin production will be reduced.

Pepsinogen is a proenzyme, or inactive precursor, of pepsin that is synthesized in the chief cells in the stomach. Pepsinogen is transformed into pepsin, a proteolytic enzyme that is active in acid environments such as the stomach, by the action of hydrochloric acid (HCl).

Pepsinogen is converted to pepsin, a more potent form of the enzyme, in the presence of an acidic pH of 2 or less, which denatures the protein that covers the active site on the pepsinogen molecule. HCl is produced by the parietal cells in the gastric glands of the stomach lining, and the secretion of both HCl and pepsinogen is stimulated by the presence of food or other digestive stimuli.

Because the enzyme is a precursor to pepsin, it is critical to the digestion process. Pepsin is critical for breaking down proteins in the stomach. Without pepsin, proteins would be broken down to a lesser extent, which might affect the absorption of nutrients. As a result, pepsinogen is vital to the digestive process and must be functioning properly.

Hence, If a mutation stops the ability for pepsinogen to respond to the presence of pepsin, pepsin production will be reduced.

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The conversion of pyruvate to phosphoenolpyruvate in gluconeogenesis requires two steps because the reaction needs to be reversed compared to the single step reaction that takes place in glycolysis.

Pyruvate to phosphoenolpyruvate conversion requires two steps, unlike the phosphoenolpyruvate to pyruvate conversion in glycolysis, which requires only one step. The reasons for this difference are as follows:

The first step involves the carboxylation of pyruvate to oxaloacetate, which is catalyzed by the enzyme pyruvate carboxylase.

The addition of carbon dioxide is the result of this reaction.ATP is used to convert oxaloacetate to phosphoenolpyruvate, which is the second step. This is accomplished by the enzyme phosphoenolpyruvate carboxykinase, which converts oxaloacetate to phosphoenolpyruvate.

ATP is required for this reaction because it has a high phosphate-transfer potential, which allows it to generate the necessary energy for the reaction. In glycolysis, phosphoenolpyruvate is formed by the dephosphorylation of 2-phosphoglycerate, which is catalyzed by the enzyme enolase.

Therefore, two steps are required to convert pyruvate to phosphoenolpyruvate in gluconeogenesis, compared to the single step that converts phosphoenolpyruvate in glycolysis.

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The main function of the cytoplasm in an animal cell is to provide a supportive environment for the cell's organelles and to facilitate various cellular processes.

In detail, the cytoplasm serves the following purposes:

1. Structural support: The cytoplasm consists of a jelly-like substance called cytosol, which provides a medium for the cell's organelles to remain suspended and maintain their structure.

2. Metabolic reactions: The cytoplasm houses numerous metabolic reactions, such as protein synthesis, glycolysis, and the citric acid cycle, all of which are vital for the cell's survival and proper functioning.

3. Transportation of molecules: The cytoplasm acts as a medium for the movement of molecules and ions within the cell. This includes the transportation of nutrients, waste products, and other essential molecules between different organelles and the cell membrane.

4. Enzyme activity: Many enzymes required for various biochemical reactions are present in the cytoplasm, ensuring proper functioning of the cell.

5. Storage of molecules: The cytoplasm serves as a storage space for molecules such as glycogen and lipids, which can be utilized when needed by the cell for energy production.

6. Cell signaling: The cytoplasm plays a crucial role in cell signaling processes, as it contains numerous signaling molecules and proteins that facilitate communication between cells and organelles.

In summary, the main function of the cytoplasm in an animal cell is to provide structural support, facilitate metabolic reactions, ensure transportation and storage of molecules, maintain enzyme activity, and play a crucial role in cell signaling.

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The function of cilia located in the trachea is to move mucus, dirt, and other small particles out of the respiratory tract.

The trachea, also known as the windpipe, is lined with pseudostratified ciliated columnar epithelium that plays a critical role in the respiratory system. The cilia present in the trachea are hair-like projections that protrude from the cells of the pseudostratified ciliated columnar epithelium. These cilia are extremely essential in trapping harmful particles and expelling them out of the body.

When we inhale, particles that get into the respiratory tract stick to the mucus that covers the trachea lining. The cilia then begin to move in coordinated, wave-like patterns to push the mucus and trapped particles out of the trachea and into the pharynx. From there, the mucus can be swallowed or coughed up. This process helps protect the lungs from harmful particles such as bacteria, viruses, and dust.

In summary, the function of cilia located in the trachea that is lined with pseudostratified ciliated columnar epithelium is to keep the respiratory tract free from unwanted foreign particles.

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The given statement is true because one strategy for purifying an expressed protein from a mixture of bacterial proteins is to modify the protein's gene to encode a series of amino acid residues at the N- or C-terminus of the protein.

This strategy, known as fusion protein expression, involves adding a sequence of amino acids to either the N- or C-terminal of the target protein. This additional sequence, called a fusion tag, typically consists of several amino acids and is used to purify the target protein from the mixture of other proteins. The fusion tag acts as a recognition site for affinity purification resins, allowing for the target protein to be selectively bound and subsequently eluted from the mixture.

Another advantage of using fusion protein expression is that it allows for increased expression levels of the target protein due to the presence of the fusion tag. Additionally, it is also possible to control the level of expression of the target protein by controlling the level of the fusion tag.

In conclusion, fusion protein expression is an effective strategy for purifying expressed proteins from a mixture of bacterial proteins. By adding a sequence of amino acids to the N- or C-terminal of the target protein, the target protein can be selectively bound and eluted from the mixture using affinity purification resins. Additionally, this strategy can also be used to increase expression levels and control the level of expression of the target protein.

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No, a mutation is not necessarily a change that results in an offspring less fit for survival than its parents.

Mutations can result in more fit offspring, no change, or less fit offspring depending on the particular mutation.

Mutations are changes in the genetic material (DNA) of a cell and can occur naturally through errors in the replication of DNA, or can be caused by environmental factors such as radiation or chemical mutagens. These mutations can be beneficial, neutral, or deleterious and may or may not result in a change of phenotype in the organism.

If a mutation is beneficial, it may result in offspring that are more fit for survival than their parents. If the mutation is deleterious, it may result in offspring that are less fit for survival than their parents. Neutral mutations have no effect on fitness and may or may not result in a change in phenotype. Regardless of the mutation, it is important to note that the offspring will always have some variation from its parents.

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Answer:  Northern Hemisphere

Explanation:  The March equinox heralds the arrival of spring in the Northern Hemisphere and autumn in the Southern Hemisphere . On this day, the sun rises due east and sets due west.

In the Southern Hemisphere the equinox occurs on September 22 or 23, when the Sun moves south across the celestial equator. According to the astronomical definition of the seasons, the vernal equinox also marks the beginning of spring, which lasts until the summer solstice (June 20 or 21) in the Northern Hemisphere

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