Answer:Magmatic density and viscosity exert fundamental controls on the eruptibility of magmas. In this study, we investigate the extent to which magmatic physical properties control the eruptibility of magmas from Iceland's Northern Volcanic Zone (NVZ). By studying subaerial flows of known age and volume, we are able to directly relate erupted volumes to magmatic physical properties, a task that has been near-impossible when dealing with submarine samples dredged from mid-ocean ridges. We find a strong correlation between magmatic density and observed erupted volumes on the NVZ. Over 85% of the total volume of erupted material lies close to a density and viscosity minimum that corresponds to the composition of basalts at the arrival of plagioclase on the liquidus. These magmas are buoyant with respect to the Icelandic upper crust. However, a number of small-volume eruptions with densities greater than typical Icelandic upper crust are also found in Iceland's neovolcanic zones. We use a simple numerical model to demonstrate that the eruption of magmas with higher densities and viscosities is facilitated by the generation of overpressure in magma chambers in the lower crust and uppermost mantle. This conclusion is in agreement with petrological constraints on the depths of crystallization under Iceland.
Explanation:
Final answer:
Increasing the volume of a mass of magma while keeping mass constant will result in a decrease in density, which is analogous to the laws governing the behavior of gases.
Explanation:
When the volume of a mass of magma increases while the mass remains constant, the density of the magma will decrease. This is because density is defined as mass per unit volume, which can be represented by the formula density = mass/volume. If the volume increases and the mass remains the same, there is more space for the same amount of mass, which results in a lower density. This concept is analogous to the behavior of gases, where increasing the volume at constant mass would similarly result in a decrease in density.
For gases, the relationships between pressure, volume, and temperature are described by the gas laws. According to Boyle’s Law, if the pressure of a gas is increased while keeping temperature constant, its volume decreases. Charles' Law states that if the volume of a gas is increased at constant pressure, the temperature also increases. According to Gay-Lussac's Law, if the volume of a gas is increased while maintaining constant temperature, the pressure decreases. Lastly, if the volume increases by adding more moles of gas at constant temperature and pressure, the volume increases in proportion to the amount of gas added.
4 characteristics of plants
The four characteristics of plants are photosynthesis, cuticle, cell walls, and reproduction.
Hey anyone what is
4x4x5 ?
Answer:
80
Explanation:
What type of actions involving the nervous system are automatic and very fast?
Answer:
A reflex action is an automatic (involuntary) and rapid response to a stimulus, which minimises any damage to the body from potentially harmful conditions, such as touching something hot. Reflex actions are therefore essential to the survival of many organisms.
Explanation:
In c4 and cam plants carbon dioxide is fixed in the _____ of mesophyll cells.
Answer:
The answer in the blank is cythoplasm.
Water supplies are treated with chlorine to kill pathogens. chlorine reacts well with many other chemicals and bacterial cells because it is a strong oxidant. however, legionella pneumophila can sometimes evade killing by residual chlorine. how does it do this? view available hint(s) water supplies are treated with chlorine to kill pathogens. chlorine reacts well with many other chemicals and bacterial cells because it is a strong oxidant. however, legionella pneumophila can sometimes evade killing by residual chlorine. how does it do this? legionella can detoxify chlorine by metabolizing it. legionella produces cations that bind up the negative chloride ions, thus inactivating them. legionella tends to be found in warm waters and in aerosols, both situations in which the chlorine readily evaporates and, thus, is in lower concentration in the water. legionella tends to form biofilms and infect other microbial cells as intracellular pathogens.
Answer:
Legionella tends to form biofilms and infect other microbial cells as intracellular pathogens.
Explanation:
The Legionella genus of the bacteria is a group of gram-negative bacteria that can cause legionnaires disease.
The Legionella pneumophila is a species of this genus which can cause legion pneumonia. The bacteria lives in the freshwater and is resistant to chemical treatment like chlorine and the biocide treatment.
The reason for this resistance is since this species form a polysaccharide layer around the colony of the bacteria which is resistant to these treatments and also the bacteria prove parasitic to the protozoans which feed on these bacteria.
Thus, the selected option is the correct answer.
Legionella pneumophila evades chlorine by forming biofilms and infecting other microbial cells as intracellular pathogens. Option D is correct .
This bacterium evades chlorination primarily because Legionella tends to form biofilms and infect other microbial cells as intracellular pathogens . When Legionella forms biofilms, it creates a protective layer that shields it from the oxidizing effects of chlorine, making it harder to eliminate.
Chlorine is a powerful oxidant and is widely used to disinfect water supplies, effectively killing a wide range of pathogens.
Challenges with Chlorination :
Chlorine can react with organic matter in the water, forming by-products like trihalomethanes (THMs), which may be harmful even at low concentrations.Some bacteria and protozoa, like Legionella and Giardia lamblia, can resist chlorination and require additional methods for removal.Legionella uses biofilm formation as a strategy to survive chlorinated environments, making understanding and tackling biofilms crucial for ensuring effective water disinfection.
Complete question :
Water supplies are treated with chlorine to kill pathogens. chlorine reacts well with many other chemicals and bacterial cells because it is a strong oxidant. water supplies are treated with chlorine to kill pathogens. chlorine reacts well with many other chemicals and bacterial cells because it is a strong oxidant.
however, legionella pneumophila can sometimes evade killing by residual chlorine. how does it do this?
A. legionella can detoxify chlorine by metabolizing it.
B. legionella produces cations that bind up the negative chloride ions, thus inactivating them.
C. legionella tends to be found in warm waters and in aerosols, both situations in which the chlorine readily evaporates and, thus, is in lower concentration in the water.
D. legionella tends to form biofilms and infect other microbial cells as intracellular pathogens.
Question 1
Where does carbon dioxide come from?
Answer:
Atmospheric carbon dioxide derives from multiple natural sources including volcanic outgassing, the combustion of organic matter, and the respiration processes of living aerobic organisms; man-made sources of carbon dioxide come mainly from the burning of various fossil fuels for power generation and transport use.
Explanation:
Carbon dioxide (CO₂) is a colourless and odourless gas that is a natural component of our air and makes up part of the carbon cycle.
Through the decomposition of organic matter, CO₂ is released into the atmosphere as part of this natural process. At the same time, photosynthesis helps to significantly reduce atmospheric CO₂ . The solubility of CO₂ in water depends on the temperature, so the oceans both produce and reduce CO₂.
Anthropogenic (man-made) carbon dioxide sources primarily relate to the combustion processes of fossil fuels. CO₂ is an inert end product that accumulates in the atmosphere and is in constant exchange with the biosphere and the oceans. Carbon dioxide reacts with water to form carbonic acid or hydrogen carbonate, which leads to a change in the pH value, i.e. the acidity of the water. Other anthropogenic CO₂ sources that intensify the greenhouse effect include changes to land usage, e.g. the clearing of forests or draining of wetlands such as moors.
It is possible to perceive depth with one eye closed because of
Answer: monocular cue
Explanation:
The key reason one don't lose sense of depth is because of monocular cue. Our brain can still detect the actual position of the object with helps of cues even if one eye is closed.
Such cues include (but are not limited to):
Linear perspective - the fact that additional objects ultimately travel to a single point (i.e. two roads that converge into a single point in the distance)Texture - objects closer to you will have more complex texture compared to objects further away from Interposition - objects closer to you will be farther away from objectsAccommodation - as you look closely at items, your eyes need to accommodate and concentrate on them using your eye muscles, giving your eyes an idea of where the object is located.Hence, Monocular Cues are used by using one eye to help sense distance.
Use the following vocabulary words in one sentence as they relate: Allele, Genotype, Phenotype
Answer:
fkf
Explanation:
what are at least 2 roles of paleontologists
Answer:
determines location of fossils.
excavates layers of sedimentary rock to locate fossils.
gathers information on the fossils (age, location, etc)
uses specific tools to excavate (chisels, drills, picks, shovels, brushes)
evaluates any discoveries by using specialized computer programs.
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Changes in the environment can alter the dynamics of natural selection in predator–prey relationships. As the planet continues to warm, climate change will have a significant effect on many of these relationships. In the case of the snowshoe hare, loss of winter snow cover could make the species more vulnerable to its predator, the lynx. The fur of snowshoe hares turns white in the winter months, providing camouflage in the snow. Which prediction would best fit a hypothesis of continued antagonistic coevolution between these two species in a year-round, snow-free environment?
Answer:
The coevolution is best explained by using the interaction of selective pressure (lyrnx) and the adaptation for survival(snowshoe/ snow)
Explanation:
The camouflage by the snow of the brown hare gives them selective advantage to remain undetected within the population during winter.since the allele for year -round brown fur within the snowshoe population, will be protected during winter by the slow, (adaptation for survival) this ensures survival, from selective pressure -Lynx, and gives them rooms for natural selection by nature for evolution.
Lynx, which preys on the brown snowshoe hares, in snow free environment will have better survival advantage for food, and therefore reproduction . Since the snow which camouflage them from the prey, has been removed by climatic change,Their population will therefore be naturally selected and evolved.
Thus the two organisms-Lynx and Snowshoe hare will co-evolve
What is not a polymer
Answer:
Elements. Metals. Ionic compounds, such as salt
Explanation:
hope this helps
A polymer is a large molecule composed of repeating subunits called monomers. Examples include nylon, polyethylene, and polystyrene. Something that is not a polymer would be a small molecule that does not consist of repeating subunits, such as water or carbon dioxide.
Explanation:A polymer is a large molecule composed of repeating subunits called monomers. These monomers are linked together through chemical bonds to form a long chain. Examples of polymers include nylon, polyethylene, and polystyrene. Therefore, something that is not a polymer would be a small molecule that does not consist of repeating subunits, such as water or carbon dioxide.
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1. You homogenize a cell and isolate it from a vesicle derivative from the endoplasmic reticulum. When their biochemistry was analyzed, they were found to have the ability to synthesize testosterone. From what type of ER are they derived and name the human body cell?
Answer:
SER, they are capable of synthesizing testosterone of Adrenocortical cells.
Explanation:
Adrenal smooth microsomal cells are enriched in smooth endoplasmic reticulum SER, membranes of which contain high levels of translocation apparatus and oligosaccharyltransferase complex proteins. STEROID-SECRETING CELLS are characterized by abundant smooth endoplasmic reticulum (SER). These cells synthesize cholesterol as a precursor for steroid hormones or take up this substrate from plasma lipoproteins. Many of the enzymes for sterol and steroid synthesis are localized in the smooth-surfaced endoplasmic reticulum. This organelle is particularly prominent in cells of the inner zones of the adrenal and fluctuates in amount and configuration in response to hormonal stimulation and sterol levels.
What must be true for natural selection to happen?
A. there must be no predators in the ecosystem.
B. Resources must be limited in the ecosystem.
C. there can be no competition for resources.
D. The population must be bellow carrying capacity.
Answer:
B.
Explanation: There must be competition for resources.
A gardener is growing plants in his backyard and decides to mate a Tall, White flowering plant (DDww) with a Dwarf, Purple (ddWW) flowering plant of the same species. When the plants start to bloom he is surprised that the pair has only produced Tall, Purple offspring. In your own words, explain how this is possible.
Answer:
Tallness allele is dominant over dwarfness allele and purple allele is dominant over white allele.
Explanation:
Tall, white flowering plant DDww was mated with dwarf, purple flowering plant (ddWW).
DDww x ddWW
Offspring: all DdWw (tall and purple)
Since all the offspring appeared tall and purple, it means that the tallness allele (D) is dominant over the dwarfness allele (d) while the purpleness allele (W) is dominant over the whiteness allele (w). Both d and w are said to be recessive.
In a trait that is defined by dominant/recessive alleles, the dominant allele always masks the expression of the recessive allele.
Denticulate ligaments are thickenings of _________ that extend and fuse with the ______ and inner surface of the _____a.arachnoid materb.dura materc.pia mater
Answer:
* ARACHNOID MATER
*DURA MATER
*PIA MATER
Explanation:
denticulate ligaments are bilateral extensions of pia mater that thickening the component of collagen of pia mater.It anchors the spinal cord to the dura mater.They are produced by the pia mater of the spinal cord.They provide stability to the spinal cord within the vertebral canal.
Arachnoid mater helps protect the brain and spinal cord from sudden impact. It is connected to the dura mater at the side that is very close to the central nervous system.
Dura mater refers to the membrane that envelops the arachnoid mater. It surrounds the dural sinuses and also provide supports to it. Dura mater carries blood from the brain toward the heart.
The pia mater is part of pseudolymphatic system and it's referred to as the thin fibrous tissue that allows blood vessels to pass through the brain.
Answer: The correct answer sequence is PIA MATER, ARACHNOID MATER AND DURA MATER.
Denticulate ligaments are thickenings of PIA MATER that extend and fuse with the ARACHNOID MATER and inner surface of the DURA MATER
Explanation: The pia mater, arachnoid mater and the dura mater are collectively known as the meninges,they are membranes that cover the brain and the spinal cord,they provide protection and support to the structures they cover.(the central nervous system)
THE PIA MATER; This is the innermost layer of the meninges,it is a thin delicate later and made up of connective tissues,it sits/adheres directly to the brain and the spinal cord and provides protection, support and metabolic needs for the central nervous system.
THE ARACHNOID MATER; This is the middle layer of the meninges,it has the appearance of a spider web,it is thin and transparent and covers the spinal cord and as well sits directly over the pia mater.there is a potential space between the pia mater and the arachnoid matter known as the the subarachnoid space,the subarachnoid space contains cerebrospinal fluid and large blood vessels which protects the brain and the spinal cord from any form of trauma and supplies nutrients to the nervous system and also removes waste products after cerebral metabolism.
DURA MATER; The dura mater is the outermost later of the meninges lying directly under the bone tissue, it is made up of irregular connective tissue,it is a thick membrane and it protects the central nervous system and the two inner laters of the meninges.the potential space between the dura mater and the arachnoid mater is know as the subdural space.
What are the 6 levels of organization for ecology
Though technically there are six levels of organization in ecology, there do exist some sources which only identify five levels, namely organism, population, communities, ecosystem, and biome; excluding biosphere from the list.
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The table shows how water in the US was used in 2010. Which statement accurately summarizes the data?
A) More water was used to farm aquatic organisms than to make products.
B) More water was used to make products than to produce electricity.
C) More water was used to produce electricity than to grow crops.
D) More water was used to grow crops than to mine land resources.
Answer:
C,More water was used to produce electricity than to grow crops.
Explanation:
Give me brainlest
Answer:
The answer is C
Explanation:
The neurons in the inferior temporal cortex....
A. send visual messages to V1, V2 and V3
B. are specialized for processing spatial information and respond differentially to the direction and speed of movement.
C. integrate motor commands with spatial information
D. respond selectively to objects quizlwt
Answer:
Option D, respond selectively to objects.
Explanation:
Inferior temporal cortex is very essential for visual processing beyond the processing done by primary visual cortex. Any issues with the inferior temporal cortex could lead to visual impairment.
IT neurons are selective is respect to dimension, shape, color, or texture and stimuli and hence they respond selectively to different stimuli, faces, highly specific complex objects.
Being highly selective, some of IT neurons respond only to the frontal face view and the remaining respond to the profiles. Because of this, these cells fail in responding to similar objects
Hence, option D is correct
Why are Mercury, Venus, Earth and Mars called the "terrestrial" planets? A. They are all made of rock. B.They have all been able to support some form of life. C.They all have solid cores. D.They all have liquid cores and rocky surfaces.
Answer:
"A" is the answer.
Explanation:
Mercury, Venus, Earth and Mars are called the "terrestrial" planets as they are all made of rock. The correct option is A.
What are terrestrial planets?A terrestrial planet, also known as a telluric planet or rocky planet, is one that is mostly made up of silicate rocks or metals.
The terrestrial planets recognized by the IAU are the inner planets closest to the Sun: Mercury, Venus, Earth, and Mars.
The planets Mercury, Venus, Earth, and Mars are referred to as terrestrial because their surfaces are compact and rocky, similar to Earth's terra firma. The terrestrial planets are the solar system's four innermost planets.
Pluto's configuration (ice, rock, and frozen gases), changing atmosphere, small size, relatively large moon, and elliptical orbit around the Sun distinguish it from the terrestrial and Jovian planets.
Thus, the correct option is A.
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What effects does water have on the formation of macromolecules?
agents of seed dispersal
Answer:
wind, water, animals, explosion and fire are the agents of seed dispersal.
Hope it will help you.The increase in plant species diversity allowed which of the following events? the evolution of complete metamorphosis in insects the evolution of flight in insects invasion of marine habitats by insects a massive increase in species diversity of insects
Explanation:
The increase in plant species diversity allowed increase in species diversity of insects
Increase in plant species defines that more plant species live in grasslands and forests as a result the more insect species find a habitat there
The presence of more plant species does not only increase insect species richness, i.e. the number of species, but also insect abundance, i.e. the number of individual
Similarly, animal diversity is not only determined by plant diversity, but also by the physical structure of the plant communities
Final answer:
The increase in plant diversity greatly influenced the evolution and diversification of insects, fostering adaptations like complete metamorphosis, flight, and specialized feeding behaviors through coevolution with flowering plants.
Explanation:
The increase in plant species diversity significantly contributed to a massive increase in species diversity of insects. The evolution of complete metamorphosis in insects, the evolution of flight in insects, and a myriad of other adaptive traits were possible largely due to the broad range of ecological niches presented by the variety of plants. This flourishing diversity is attributed to multiple factors including pollination, herbivory, and the coevolution of insects and flowering plants.
During the coevolutionary process, flowering plants developed various colors, shapes, scents, and even food supplies to attract specific insects for pollination, while insects evolved the necessary mouthparts, senses, and flight patterns to benefit from these floral offerings. This coevolution created a positive feedback loop, resulting in an evolutionary arms race that expanded the diversity of both plants and insects. Some insects were repelled while others were attracted, each evolving complex adaptations in response to the other's defenses or offerings.
The relationships formed through these interactions were critical for both parties, leading to the diverse and complex ecosystems we witness today. As coevolution continued, the range of insect behaviors and physical traits expanded, allowing them to exploit the varied plant life that emerged after the disappearance of dinosaurs and flourish in numerous environments.
Adults with more than a 12-month history of migraines were assigned randomly in a double-blinded study to receive treatment with experimental drug X (10 or 20 mg/day) or placebo. The primary efficacy measure was the reduction in severity of the migraine attacks. Enrollment was 1,200 subjects. Which of the following best describes the clinical phase of this study?
Answer:
Phase III
Explanation:
The given condition fall in the trial phase (Phase III) of cinical study which aims to:
- Determine drug's effectiveness (primary goal)
- Determine long-term drug safety
- Confirm findings
In Phase III, randomised, double-blind, placebo-controlled, parallel group study is majorly to evaluate the efficacy and safety of placebo in episodic migraine prevention in children (6 to < 12 years of age) and adolescents (12 to < 18 years of age).
The trial consists of four phases: screening; double-blind therapy period for 24 weeks in which placebo or Erenumab is given to subject as dose 1, dose 2 or dose 3 (based on the participant's body weight) once a month via subcutaneous injection; optional dose level blinded extension phase (40 weeks) which involves subjects recieve dose1, 2 and 3 of placebo, and at last it follows a safety follow-up phase for 12 weeks (after 16 weeks of the last dose of investigational drug).
Hence, the clinical phase is phase III.
The study described can best be classified as b. Phase III clinical trial.
Here’s why:
Enrollment of 1,200 subjects - Phase III trials typically involve a larger number of patients, usually ranging between 1,000 and 3,000 participants. This is consistent with the enrollment figure given in the study.
Primary efficacy measure - Phase III trials are designed to establish the efficacy of a new drug compared to existing treatments or a placebo. In this case, the primary efficacy measure is the reduction in severity of migraine attacks, which aligns with the goals of a Phase III trial.
Double-blind study - Double-blind studies are a hallmark of Phase III clinical trials. In such studies, neither the participants nor the researchers know who is receiving the experimental drug and who is receiving the placebo. This is done to eliminate bias and ensure the reliability of the results.
Experimental drug X vs placebo - Comparing the experimental drug to a placebo is a standard approach in Phase III trials. This helps determine the drug’s therapeutic effect and its benefits versus risks.
Complete question:
Adults with more than a twelve (12)-month history of migraines were assigned randomly in a double-blinded study to receive treatment with experimental drug X (10 or 20 mg/day) or placebo. The primary efficacy measure was the reduction in severity of the migraine attacks. Enrollment was twelve-hundred (1200) subjects. Which of the following best describes the clinical phase of this study?
a. Phase II b. Phase III c. Preclinical d. Phase I
The non-leukocyte tissue cells known as ________ activate enzymes which produce leukotrienes and prostaglandins in response to allergen binding. The non-leukocyte tissue cells known as ________ activate enzymes which produce leukotrienes and prostaglandins in response to allergen binding. A. mast cells B. basophils C. monocytes D. lymphocytes E. neutrophils
Answer:
Mast cells. (Ans. A)
Explanation:
Mast cells are called the immune system of vertebrate species, they help to regulate some allergic responses, innate & adaptive immunity, and inflammation such as hypersensitivity. These cells circulate the amounts of their granules into the surrounding tissues, while stimulation by an allergen found and the process called degranulation.
Mast cells help to assist and awaken the immune system to local infection. Once these cells are activated, they generate inflammatory responses by secreting chemical mediators which are stored in preformed granules, and after activation occurs synthesizing leukotrienes and cytokines.
Based on what you learned in the lab why does your body need to break down starch into glucose
Starch and glucose are carbohydrates (sugars). The body breaks the starch molecules into glucose as the former is too large to diffuse into cells. Thus, option B is correct.
What are simple and complex sugars?
Simple sugars are carbohydrates that are monomers and have a small size due to a single molecule composition. On the other hand, complex sugars are large chains with many molecules.
Starch is a complex sugar, is large, and made of glucose molecules linked to form the polysaccharide. Their large size hinders their movement in the cell through the semipermeable membrane.
Therefore, the starch is broken down into glucose for easy transportation.
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The complete question is attached to the image below.
The _____________ cells in the _________________ of a nephron can cause and increase or decrease in body pH. A. intercalated; collecting duct B. principal; proximal convoluted tubule C. macula densa; distal convoluted tubule D. glomerular; nephron loop
Answer:
The intercalated cells in the distal convoluted tubule of a nephron can cause and increase or decrease in body pH.
Explanation:
The renal collecting duct is the nephron segment where the final urine content of acid equivalents and inorganic ions are determined.
Two types of cells regulate the acid-base and volume homeostasis.
Intercalated cells, which express acid-base transporters and vacuolar H+-ATPase, maintain an apropriate acid-base balance and principal cells that express the epithelial sodium channel ENaC and aquaporin 2, regulate electrolyte reabsorption.
Filtered bicarbonate is predominantly reabsorbed from the proximal convoluted tubule about 80% and the remaining bicarbonate is reabsorbed from the thick ascending limb of the loop of Henle, the distal nephron, specifically the distal convoluted tubule & the connecting tubule, and finally the cortical and both the outer and inner medullary collecting duct.
Intercalated cells are enriched in mitochondria, and express proteins involved in transport of proton equivalents such as vacuolar H+-ATPase, carbonic anhydrase II and bicarbonate transporters. There are two types of intercalated cells Type-A and Type-B.
Answer:
hmmm
Explanation:
hmmmmm
If you made an artwork to send a message to your
comunity, what could your message be?
Answer:
If I was to send a message right now during the corona virus to my community, I would say to be thankful and stay healthy because death will never wait for anyone.
Explanation:
if my ans helped u, pls mark it as brainliest! thx!
Answer:
2.2.4 Journal
Explanation:
The myelin on myelinated neurons can be degraded or destroyed in diseases such as multiple sclerosis-a process called demyelination. If a myelinated neuron was affected by demyelination, how would this affect action potentials in that neuron?
Answer:
The speed of action potential propagation get slower downExplanation:
Myelination is the process of generating myelin in neurons. In CNS, oligodendrocyte make the myelin sheath.
The main function of myelin is to increase the speed of electrical impulses along the myelinated fiber.
Myelinated fibers lack voltage-gated sodium channels along the myelinated internodes, having them only at the nodes of Ranvier though which the molecules moves.
Demyelination is the loss of the myelin sheath, result due to some neurodegenerative autoimmune diseases, resulting in the decrease of the speed of action potential propagation.
Final answer:
Demyelination of a myelinated neuron slows down the conduction of action potentials by causing current leaks. The myelin sheath acts as an insulator, increasing the speed of conduction. Nodes of Ranvier play a crucial role in regenerating the action potential.
Explanation:
Demyelination of a myelinated neuron will affect action potentials in that neuron by slowing down the conduction of the action potential. The myelin sheath acts as an insulator and prevents current from leaving the axon, which increases the speed of action potential conduction. When the myelin is degraded or destroyed, current can leak from previously insulated axon areas, causing a decrease in the speed of action potential conduction. The gaps in the myelin sheath, called nodes of Ranvier, play a crucial role in regenerating the action potential. Without these nodes, the action potential would propagate very slowly.
How does the body regulate the distribution of oxygen and glucose to different body tissues?
A. By changing aortic blood pressure and thus the velocity of blood flow in capillaries.
B. Using valves in veins, which close due to backpressure from the column of blood above them.
C. Using valves found inside arterioles near capillaries.
D. By constricting smooth muscle throughout the capillaries. Via relaxation/constriction of pre-capillary sphincters.
Answer:
a would because blood would also need to flow
Explanation:
Evidence indicates that plants increase the number of stomata in their leaves as atmospheric CO2‚ levels decline. Increasing the number of stomata per unit surface area should have the effect of doing which of the following?
1. increasing dehydration of leaf tissues
2. decreasing dehydration of leaf tissues
3. countering the effect of declining CO2‚ on photosynthesis
4. reinforcing the effect of declining CO2‚ on photosynthesis
5. decreasing the O2‚ content of air next to the leaves lower than it would otherwise be
6. increasing the O2‚ content of air next to the leaves higher than it would otherwise be
a. 1, 3, and 5
b. 1, 3, and 6
c. 1, 4, and 5
d. 2, 3, and 6
e. 2, 4, and 5
Answer:
E
Explanation: