Before pyruvate oxidation, pyruvate must be produced through the process of glycolysis in the cytoplasm of the cell. During glycolysis, glucose, a six-carbon molecule, is broken down into pyruvate, a three-carbon molecule. This process releases a small amount of energy in the form of ATP and NADH. After the pyruvate is produced, it is transported from the cytoplasm into the mitochondria, where pyruvate oxidation occurs. Before pyruvate can be oxidized, it must first be converted into acetyl-CoA through a series of reactions that remove a carbon dioxide molecule from each pyruvate molecule and transfer the remaining two-carbon fragment to Coenzyme A (CoA). The resulting acetyl-CoA can then enter the Krebs cycle, also known as the citric acid cycle, where it is further oxidized to generate more ATP and reduce electron carriers.
Cattle trample and kill small plants surrounding a water hole as they stand near it to drink water. This is an example of:
The phenomenon you're telling is an example of "trampling," which is when the hooves of large animals destroy or damage soil and verdure. In this particular case, the steers are stomping on and killing little plants around the water opening as they stand close to it to hydrate.
This happens a lot in places where a lot of big herbivores congregate around water sources, and it can have big effects on the environment, like soil erosion and how the plant community changes.
The condition of the soil deteriorates as a result of poor use or management, typically for agricultural, industrial, or urban purposes. It's a serious issue for the environment. Soils are a key regular asset and are the reason for all earthly life.
Actually, desertification is the process of soil erosion. Most of the time, it involves getting rid of nutrient-rich topsoil, leaving behind coarse, sandy particles that can't hold in water. Consequently, those areas that are unsuitable for plant growth will eventually become deserts.
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How much does myelination reduce the effective capacitance of the membrane?
Myelination reduce the effective capacitance of the membrane by more than 10-fold.
Myelin has a high lipid content (about 80%), which enables it to function as an insulator along the internodal segments (high transverse resistance and low electrical capacitance).
Myelin reduces the internode's capacitance, making it easier to charge and hastening the propagation of action potentials. However, the resistance of the myelin-containing oligodendrocyte membranes also raises the axon's effective membrane resistance, thereby expanding its electrical space and "insulating" it.
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which of the following would gram stain negative? choose one or more: a. proteobacteria b. escherichia coli c. clostridium difficile d. bacteroidetes e. mycobacterium paratuberculosis f. firmicutes g. enterococcus faecalis
Proteobacteria and Escherichia coli would gram stain negative. Hence option A and B are correct.
A Gram stain test looks for bacteria in areas where an infection is thought to have occurred, including the throat, lungs, genitalia, and skin wounds. Gram stains can also be used to examine the presence of germs in bodily fluids like blood or urine.
Gram-positive and Gram-negative infections are the two primary subtypes of bacteria. Based on how the bacteria respond to the Gram stain, the several types are identified. The hue of a Gram stain is purple.
The bacteria in a sample will either stay purple or change pink or red when the stain and bacteria interact. The bacteria are Gram-positive if they continue to be purple. The bacteria are Gram-negative if they turn pink or crimson.
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1. According to the endosymbiotic theory, how did membrane-bound organelles, such as the nucleus and endoplasmic reticulum form?
The endosymbiotic theory holds that the process of endocytosis, in which a prokaryotic cell envelopes another prokaryotic cell to form a symbiotic relationship, is how membrane-bound organelles like the nucleus and endoplasmic reticulum evolved.
What is the endosymbiotic hypothesis for the development of organelles?A large host cell and ingested bacteria might easily form a lifelong partnership and depend on one another for survival, according to the endosymbiotic notion. North of millions of long stretches of advancement, mitochondria and chloroplasts have become more specific and today they can't live external the cell.
What is the explanation for the endosymbiotic theory?According to the Endosymbiotic Theory, the mitochondria and chloroplast in eukaryotic cells were once aerobic bacteria (prokaryotes) that a large anaerobic bacteria (prokaryotes) ingested. Before being eaten by anaerobic bacteria, the aerobic bacteria started out as free-living prokaryotes.
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What age do Moro and grasp reflexes stop
Moro reflex stops after 2 months while Palmar Grasp reflex stops after 5-6 months and Plantar Grasp stops after 9-12 months.
Numerous reflexes are visible during birth, including the Moro reflex. After three to four months, it usually disappears. When a baby is shocked or feels like they are falling, a reflex known as the Moro reflex occurs naturally.
The neurological examination of newborns includes a standard check for the Palmar grasp reflex. It can help in the diagnosis of some illnesses, such as cerebral palsy or peripheral nerve damage, even if its only phylogenetic role is involved.
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: Level I: Reviewing Facts and Terms (Bloom's Taxonomy: Knowledge)
21) ACE converts
A) renin to angiotensinogen.
B) angiotensinogen to angiotensin I.
C) angiotensin I to angiotensin II.
D) angiotensin II to aldosterone.
E) renin to aldosterone.
ACE converts Angiotensinogen to angiotensin I. The answer is B)
Angiotensin-converting enzyme (ACE) is an enzyme found in the lungs and blood vessels that converts angiotensinogen, a protein produced by the liver, into angiotensin I. Angiotensin I is then further converted to angiotensin II by another enzyme, angiotensin-converting enzyme 2 (ACE2).
Angiotensin II is a potent vasoconstrictor, meaning it narrows blood vessels, and also stimulates the release of aldosterone, which increases blood pressure and sodium retention in the kidneys. By converting angiotensinogen to angiotensin I, ACE plays a key role in regulating blood pressure and fluid balance in the body.
ACE inhibitors, a class of drugs commonly used to treat high blood pressure, block the activity of ACE, leading to decreased levels of angiotensin II and aldosterone, and a resulting decrease in blood pressure.
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If the lysosome breaks, what protects the rest of the cell from lysosomal enzymes? a. The reducing environment of the cytosol. b. The increased pH of the cytosol. c. The increased glycosylation of plasma membrane proteins d. The decreased pH of the cytosol. e. The increased Ht in the cytosol.
Answer:
D. The decreased pH of the cytosol
Explanation:
The lysosome contains many different types of enzymes that are responsible for breaking down different types of biomolecules. If the lysosome breaks, the enzymes may leak out into the cytosol, which can be damaging to the rest of the cell. To prevent this from happening, a number of different protective mechanisms are in place. One such mechanism is the decreased pH of the cytosol compared to the lysosome. The lysosomal enzymes are optimized to function in an acidic environment, so if they leak out into the cytosol, their activity will be greatly reduced due to the higher pH of the cytosol. Additionally, the glycosylation of plasma membrane proteins can help to protect the cell from lysosomal enzymes by providing a physical barrier that prevents the enzymes from entering the cell. The reducing environment of the cytosol may also help to prevent damage by neutralizing any free radicals that are generated by the lysosomal enzymes. Overall, the decreased pH of the cytosol is the most important protective mechanism against lysosomal enzyme leakage.
Name the organisms that have fur and mammary glands (Look on SG)
Fur and mammary glands are distinguishing features of mammals, a diverse group of animals that includes over 6,000 species.
Mammals are distinguished by the presence of fur or hair, mammary glands that produce milk to nourish their young, and the ability to regulate their own body temperature.
Fur, which is composed of protein fibers known as keratin, serves as insulation and protection for mammals.
Mammary glands are another distinguishing feature of mammals. These are specialised glands that produce milk in order to feed their young.
Thus, the presence of fur and mammary glands are defining characteristics of mammals that play important roles in their survival and reproduction.
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True or False? The stapes bone in your ear is smaller than a grain of rice.
The stapes bone, which is one of the three bones in the center ear, is the littlest bone in the human body. It has the shape of a stirrup and is about the same length as a grain of rice, about 3 to 4.5 millimeters.
The stapes is the smallest bone in the human body and the third of the three ossicles in the middle ear. It estimates around 2 to 3 mm, more prominent along the head-base range.
The stapes are the body's littlest bone! Some of the time called the stirrup, this fragile bone works with two others in the ear to send sound vibrations into the internal ear.
The human body's smallest bone is about the size of a rice grain. The stapes bone is the name of this bone.
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which of the following represent mechanisms by which proteobacteria generate a proton motive force for atp synthesis? choose one or more: a. aerobic oxidation of h2s b. photolysis of h2o c. anaerobic oxidation of glucose d. reduction of co2 by h2 e. light-driven proton pumps
Proteobacteria are known to generate a proton motive force that powers ATP synthesis through various mechanisms. One of the ways is the aerobic oxidation of H2S, which involves the transfer of electrons from H2S to oxygen, generating a proton motive force. A, C, D, and E are the proper responses.
Another mechanism is the anaerobic oxidation of glucose, where glucose is broken down into smaller molecules, releasing electrons that create a proton gradient across the membrane. Reduction of CO2 by H2 is also a mechanism where electrons are transferred, generating a proton motive force.
Additionally, light-driven proton pumps are another way by which proteobacteria generate a proton motive force, where light energy is used to pump protons across the membrane. Photolysis of H2O, on the other hand, is not a mechanism used by proteobacteria for generating a proton motive force.
Therefore, the correct answers would be a, c, d, and e.
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: Level I: Reviewing Facts and Terms (Bloom's Taxonomy: Comprehension)
38) The most important factor affecting the pH of plasma is the concentration of
A) lactic acid.
B) ketone bodies.
C) organic acids.
D) carbon dioxide.
E) hydrochloric acid.
The most important factor affecting the pH of plasma is the concentration of carbon dioxide. The correct option is D.
A byproduct of cellular metabolism called carbon dioxide is carried by the blood to the lungs where it is exhaled out of the body. Blood water and carbon dioxide can combine to form carbonic acid, which can split into bicarbonate and hydrogen ions. Red blood cells contain the enzyme carbonic anhydrase, which is responsible for catalyzing this reaction.
The pH of the plasma is influenced by the amount of carbon dioxide in the blood because higher levels of carbon dioxide can result in the production of more carbonic acid, which raises the concentration of hydrogen ions and lowers the pH. Respiratory acidosis is what is meant by this. The correct option is D.
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as osteoblasts release matrix materials around themselves, they become enveloped by the matrix and differentiate into...
The differentiation of osteoblasts into osteocytes is a critical step in the development and maintenance of bone tissue, and it is essential for the proper functioning of the skeletal system.
As osteoblasts release matrix materials around themselves, they become enveloped by the matrix and differentiate into mature bone cells known as osteocytes. Osteocytes are the most abundant cells found in mature bone tissue, and they are responsible for maintaining the bone tissue by regulating the mineralization and turnover of the bone matrix.
Osteocytes have long, branched processes that extend into the bone matrix, allowing them to communicate with other osteocytes and with osteoblasts and osteoclasts. They play a crucial role in maintaining bone homeostasis by sensing mechanical strain and adapting the bone tissue accordingly.
This process, known as bone remodeling, involves the removal of old or damaged bone tissue by osteoclasts and the formation of new bone tissue by osteoblasts.
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in the example of the two species of lobelia given in the textbook, one species showed semelparity and the other showed iteroparity. a difference in which factor was most responsible for this difference in life history strategy?
The difference in the factor of survival and reproduction was most responsible for the difference in life history strategy between the two species of Lobelia.
Semelparous species, such as the Lobelia telekii, typically have a short lifespan and reproduce only once in their lifetime, with the aim of producing as many offspring as possible to ensure the survival of the species.
This strategy works well in environments where survival rates are low, and resources are limited.
Iteroparous species, such as the Lobelia polyphylla, have a longer lifespan and reproduce multiple times in their lifetime, with the aim of producing fewer offspring but ensuring a higher survival rate for each offspring.
This strategy is more successful in stable environments where resources are more abundant, and survival rates are higher.
Therefore, the difference in the factor of survival and reproduction is the most responsible factor for the difference in life history strategy between the two species of Lobelia.
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Which of the following identifies why the hypothesis is null in the following scenario?
The following hypothesis is proposed for a study: Tomato plants show no difference in growth rate when planted in compost rather than soil.
Responses
The statement makes a prediction.
The items in the statement have a cause-effect relationship.
The items in the statement are unrelated.
The statement specifies a relationship.
The correct response is "The statement specifies a relationship".
What is Hypothesis?
A hypothesis is a proposed explanation or prediction for a phenomenon or observed event, based on limited evidence or previous observations. It is a tentative and testable statement that suggests a possible relationship between variables. The purpose of a hypothesis is to guide research and experimentation, by providing a focused and testable question that can be investigated to determine its validity.
A null hypothesis always assumes that there is no relationship or no difference between the variables being compared in the study. In this scenario, the null hypothesis is that there is no difference in the growth rate of tomato plants planted in compost versus soil.
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WAD: Headache- _______ headaches are characteristic of sprains of the UPPER cervical spine
Answer:
cervicogenic headache (CGH)
Explanation:
cervicogenic headache (CGH) presents as unilateral pain that starts in the neck and is referred from bony structures or soft tissues of the neck. [1] It is a common chronic and recurrent headache that usually starts after neck movement. It usually accompanies a reduced range of motion (ROM) of the neck.
What are the clinical signs of sarcoptic mange and how is the diagnosis confirmed? What is currently the favorite treatment?
In dogs, severe itching is sarcoptic mange's defining symptom. The itching can lead to secondary symptoms like redness, dandruff, hair loss, small bumps, and scabs as the condition gets worse.
What symptoms do sarcoptes mites present clinically?The human itch mite (Sarcoptes scabiei var.) infects the skin and causes human scabies. hominis). The tiny scabies mite lives and lays its eggs in a burrow in the upper layer of the skin. Scabies is characterized by intense itching and a rash on the skin that resembles a pimple.
What are the clinical indications of sarcoptic mange in creatures?The sarcoptic mite causes severe itchiness when it is present. A dog with the condition will constantly scratch and chew on his skin. This prompts a lot of going bald, particularly on the legs and stomach. The skin will eventually become thicker and darker over time.
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if the haploid number of chromosomes for a certain species of animal is 6, the diploid number would be
If the haploid number of chromosomes for a certain species of animal is 6, the diploid number would be 12.
In sexually reproducing organisms, cells have two sets of chromosomes, one from each parent. This is referred to as the diploid number, denoted as 2n. Haploid cells, on the other hand, contain only one set of chromosomes, represented as n.
During sexual reproduction, haploid cells called gametes (sperm and eggs) are produced by the process of meiosis. When these gametes combine during fertilization, a new diploid cell called a zygote is formed, which then develops into a new organism.
In the given example, the haploid number (n) is 6, meaning that each gamete contains 6 chromosomes. When sperm and egg cells unite during fertilization, the resulting zygote will have a total of 12 chromosomes (6 from each parent), which is the diploid number (2n). This ensures that the offspring have the same number of chromosomes as their parents, maintaining genetic continuity and stability across generations.
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third generation progestins and drospirenone are associated with which possible side effect?
Third-generation progestins and drospirenone, which are commonly used in hormonal contraceptives, are associated with an increased risk of venous thromboembolism (VTE) or blood clots.
This risk is higher with drospirenone-containing contraceptives compared to those containing other progestins. Other possible side effects of hormonal contraceptives include nausea, headaches, breast tenderness, weight gain, and mood changes.
It's important to discuss the potential risks and benefits of different types of contraceptives with your healthcare provider to determine the best option for you.
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Too much activity on androgen receptors results in which side effects?
Too much activity on androgen receptors can result in various side effects. Androgens are male sex hormones, and excess activity on their receptors such as the growth of facial hair, deepening of the voice.
In males, excessive androgen activity can cause the opposite effect, such as gynecomastia or the development of tissue. Other side effects of excess androgen activity include acne, oily skin, and male pattern baldness.
Additionally, excess androgen activity may increase the risk of prostate cancer in men. It's important to note that the specific side effects can vary depending on the type and dose of androgen receptor agonist being used.
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12 - 3 RNA and Protein Synthesis: Describe the three main differences between RNA and DNA.
The three main differences between RNA and DNA is that DNA is double stranded whereas RNA is single stranded, DNA contains the base thymine whereas RNA contains uracil and a DNA is more stable than RNA.
Nucleic acids are basically of two types which is an RNA as well as a DNA. The DNA and RNA very different from each other structurally. The DNA is usually found to be double stranded whereas the RNA is single stranded.
The nitrogenous bases which are present in the DNA are the thymine, cytosine, guanine and adenine whereas in the RNA the thymine is replaced by the uracil in RNA. The DNA is also more heat stable as compared to the RNA.
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102. Drinking coffee after drinking alcohol
A. Decreases blood alcohol content.
B. Increases blood alcohol content.
C. Cancels the effect of the alcohol.
D. Has no effect on blood alcohol content.
Answer:
D, The only way to decrease blood alcohol content is to wait for the body to metabolize and eliminate the alcohol naturally over time.
what is the mid line of myosin fibers called in a sarcomere?
The midline of myosin fibers in a sarcomere is called the M-line. The M-line is a dark line that runs vertically through the center of the sarcomere and is formed by proteins that hold the myosin filaments in place.
The M-line provides structural support for the sarcomere and helps to maintain the alignment of the myosin filaments during muscle contraction. The M-line also serves as an attachment site for other proteins, such as titin, which plays a role in maintaining the elasticity of the muscle.
The M-line is a critical component of the sarcomere and is essential for the proper functioning of skeletal muscle.
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2. What would offering tax breaks for companies investing in clean energy do?
O A. It would allow companies to use more energy.
O B. It would push the industry to follow the public's preferences.
OC. It would remind an industry of its ecological footprint.
O D. It would tip the economic balance to make clean energy more profitable.
The correct option is D. It would tip the economic balance to make clean energy more profitable.
Tax equity: what is it?Project funding through the use of tax advantages and cash flow created by the project is provided by tax equity. Tax credits and deductions are included in these advantages. Equity taxes for solar energy plants would come from perks such.
What distinguishes investment credit from production credit?Production tax credits and investment tax credits differ significantly in that one continues to pay out depending on the quantity of a product generated, such as wind energy, while the other needs real money to be invested in order to benefit from the credit.
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What is a "species-area" curve and what relationship does it generally depict?
A species-area curve is a graph depicting the relationship between the size of a habitat and the number of species present in that habitat.
In general, the environment contains more species the larger it is. The number of species often grows as the area increases in this connection, which is typically represented by a logarithmic curve.
The species-area curve is used to evaluate a habitat's diversity as well as the effects of habitat modifications on species diversity.
Additionally, it is used to assess the richness of various ecosystems and forecast how changes in habitat size would affect species diversity.
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how are glycolysis, ethanol fermentation, and lactate fermentation all related? a. all are regulated by the atp/adp mass-action ratio. b. all three produce carbon dioxide. c. all can proceed in the absence of oxygen. d. all require pyruvate. e. all three produce nadh
The glycolysis pathway breaks down glucose into two pyruvate molecules and produces two ATP molecules, two NADH molecules, and two molecules of water. So, the correct answer is option e.
Pyruvate is transformed into ethanol and carbon dioxide during the anaerobic process of ethanol fermentation, with NADH being recycled back into the glycolysis pathway.
Pyruvate is transformed into lactic acid during the lactate fermentation process, and NADH is recycled back into the glycolysis route as well. NADH is a by-product of all three processes, including glycolysis, ethanol fermentation, and lactate fermentation.
Having the ability to give electrons to other molecules, the potent reducing agent NADH can provide energy for metabolic processes.
As a result, NADH is crucial in supplying cells with energy when there is no oxygen present.
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what membrane protein in a neuron helps establish the electrochemical gradient?
The membrane protein in a neuron that helps establish the electrochemical gradient is the sodium-potassium ATPase pump (Na+/K+ ATPase pump).
The Na+/K+ ATPase pump is an essential membrane protein that plays a crucial role in maintaining the resting membrane potential of a neuron by pumping sodium ions out of the cell and potassium ions into the cell. This creates an electrochemical gradient across the cell membrane, where the concentration of sodium ions is higher outside the cell and the concentration of potassium ions is higher inside the cell.
The pump uses energy from ATP hydrolysis to move three sodium ions out of the cell and two potassium ions into the cell, thereby maintaining the concentration gradient of these ions across the cell membrane. This process is important for several neuronal functions, including the generation of action potentials, neurotransmitter release, and the maintenance of ionic homeostasis in the neuron.
Thus, the Na+/K+ ATPase pump is a critical membrane protein that helps establish and maintain the electrochemical gradient in neurons, which is essential for their proper functioning.
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As long as we are discussing parasites, what two species of nose bots have been found in llamas? What are the signs, and how would a practitioner treat for this possibility?
Nose bots are indeed a parasitic issue that can affect llamas. The two species of nose bots found in llamas are Cephenemyia spp. and Oestrus ovis. These parasites are fly larvae that typically infest the nasal passages and sinuses of their host, causing discomfort and potential health issues.
Signs of nose bot infestation in llamas may include nasal discharge, sneezing, head shaking, irritation, and respiratory distress. In severe cases, the infestation can lead to secondary infections or even damage the host's sinus and nasal structures.
To diagnose and treat nose bots in llamas, a veterinary practitioner would first examine the animal for clinical signs and may perform a nasal endoscopy to visualize the larvae. Treatment typically involves the administration of an appropriate parasiticide, such as ivermectin, to kill the larvae.
In some cases, manual removal of the larvae may be necessary if they are causing significant discomfort or if they cannot be effectively treated with medication. Additionally, the practitioner may recommend preventive measures, such as fly control strategies, to minimize the risk of future infestations.
In summary, Cephenemyia spp. and Oestrus ovis are the two species of nose bots found in llamas, with signs including nasal discharge and irritation. A practitioner would likely treat this issue with parasiticides and, in some cases, manual removal, while also recommending preventive measures.
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Write the scientific name for gray wolf, canis lupus, using proper formatting. What are the rules of binomial nomenclature?
The scientific name for gray wolf is Canis lupus according to binomial nomenclature.
In binomial nomenclature, the first word represents the genus and the second word represents the species. The genus name is always capitalized, while the species name is written in lowercase. Both names are italicized or underlined when written (e.g., Canis lupus).
Binomial nomenclature is a naming system used to give unique names to different species of living organisms. It was developed by Carolus Linnaeus in the 18th century and is still used today by scientists to describe and classify different species.
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what is impulse propagation. does an action potential move in more than one direction along the axon?
are the following statements true or falseaction potentials are all-or-nothingaction potentials ultimately cause release of transmitters into synaptic cleft
The phrase "all-or-nothing nature of action potentials" alludes to the fact that an action potential will be triggered and propagated along the axon once a specific threshold degree of depolarization is met.
The synaptic cleft, which is the tiny space between the pre-synaptic neuron and the post-synaptic neuron, is where neurotransmitters are ultimately released as a result of this action potential. The voltage-gated calcium channels open when the action potential reaches the end of the axon, allowing calcium ions to enter the cell. The release of neurotransmitters from vesicles in the pre-synaptic neuron into the synaptic cleft is then triggered by the influx of calcium ions.
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--The complete Question is, What is the relationship between the all-or-nothing nature of action potentials and the release of neurotransmitters into the synaptic cleft? --
