Men who maintain their testosterone levels beyond the age of 50 show better preservation of visual, verbal, and visual-spatial abilities.
Testosterone is the hormone present in male. It is produced in the testicles. The hormone is very useful in maintenance of bone density. fat distribution, muscle strength and mass., etc. It is also necessary for development of male reproductive tissues such as testes and prostate.
Visual-spatial ability is the ability to analyze the locations of the 2-dimensional and 3-dimensional figures. A person must be able to tell what the object is, how far or near it is from the person, etc. Some skills do not require any learning but many require some practice such the tying show laces.
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the export of mrnas outside the nucleus requires several proteins that are post-translationally modified by:
The export of mrnas outside the nucleus requires several proteins that are post-translationally modified by phosphorylation.
What is phosphorylation?
phosphorylation is the name for the process of adding a phosphate group to a molecule, such as a sugar or protein.
By altering the protein's structure, phosphorylation controls protein activity and cell signaling. The protein may be impacted by these modifications in one of two ways. First, the protein's catalytic activity is controlled by conformational alterations.
A sensitive and dynamic method of controlling protein activity, stability, protein interaction, and sub cellular localization is provided by phosphorylation.
Therefore, the export of mrnas outside the nucleus requires several proteins that are post-translationally modified by phosphorylation.
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As the frequency of muscle action potentials _______________, the strength of the resulting muscular contraction ____________.
As the frequency of muscle action potentials Increased the strength of the resulting muscular contraction summation .
Twitch, summation, and tetanus are three main categories that describe the intensity of skeletal muscular contractions. An action potential generated within the muscle fibre itself causes a single contraction and relaxation cycle, which is known as a twitch. The amount of force generated by a muscle varies depending on how many motor units are functioning at once. Elwood Henneman and his Harvard Medical School colleagues discovered in the 1960s that continuous increases in muscular tension may be induced by gradually raising the activity of axons that serve as input to the pertinent population of lower motor neurons. The recruitment of the motor units in a fixed order based on their size is what causes this gradual increase in tension.
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which of the following are stages in the metabolic control of the lac operon? select all that apply. rna polymerase attaches to the accessible promoter and transcribes the genes. when lactose is present, it binds to the repressor and causes the repressor to release the operators. in the absence of lactose, a repressor binds to the two operators, preventing rna polymerase from attaching to the promoter.
The correct answer based on the above made statements about the stages involved the control of the lac operon is:
when lactose is present, it binds to the repressor and causes the repressor to release the operators.
The answer is option b.
How the presence of lactose controls the release of lac operonThe release of the operators, the lac operon; thus occur at the presence lactose in the cell environment. This however makes it possible for it release when lactose itself crosses the membrane of the cell; thereby acting as an inducer of the operon and stimulate the repressor to release the operators.
So therefore, it can be deduced from the step by step explanation above that during the metabolic reactions which occurs in our system, the lac operon are being induced to be released by the the contributing lactose.
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What will happen when the ribosome shifts one codon further on the mrna, assuming the next codon is not a stop codon? select all that apply.
Answer:
The tRNA that is shown in the A site in the figure above will be ejected from the ribosome. A new tRNA will bind to the ribosome.
Explanation:
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if a mutation rendered the signal recognition particle nonfunctional, what would be the most obvious effect on the cell?
If the mutation makes the signal recognition particle malfunction, then the effect on the cell is all the proteins normally secreted by the cell will remain partially formed and adhere to the endoplasmic reticulum.
What is particle signal recognition?
The signal recognition RNA particle is part of the ribonucleoprotein signal recognition particle (SRP) complex. SRP recognizes the signal peptide and binds to the ribosome, reads protein synthesis. SRP receptors are membrane-embedded proteins and contain transmembrane pores. When the SRP-ribosome complex binds to the SRP receptor, the SRP releases the ribosome and is washed away. The ribosome continues protein synthesis, but now the protein moves through the transmembrane pore of the SRP receptor.
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You would like to decrease the number of times a student sharpens her pencil during class. However, you do not want to completely eliminate this behavior. Which type of reinforcement program makes the most sense?.
Differential Reinforcement of Low Rates (DRL) is the reinforcement program.
What is DRL?
The DRL's primary objective is to improve other drivers' visibility of your car. DRLs are frequently manufactured using LED lights rather than halogen headlight bulbs because they are not intended to illuminate the road. LED DRLs emit a bright white light, are energy-efficient, and have a long lifespan.
Differential reinforcement of alternate behavior, differential reinforcement of incompatible behavior, differential reinforcement of other behavior, and differential reinforcement of low rates are the four categories that have received the most research.
Differential reinforcement comes in four main forms:
Differential Reinforcement of Compatibility (DRI)Differential reinforcement for different types of behavior (DRA)Differential reinforcement for different actions (DRO)Low Rate Differential Reinforcement (DRL).To learn more about DRL refer to:
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which is not an example of mutualistic coevolution? group of answer choices host/pathogen plant/pollinator plant/mycorrhizae rumen bacteria/cows
Host/pathogen isn't an instance of mutualistic coevolution. In mutualistic coevolutionary interactions, each species broaden variations for the gain of each organisms. In commensalistic interactions, one species blessings from the connection at the same time as the opposite isn't harmed.
Coevolution is not unusualplace amongst organisms collaborating in a mutual interaction. In mutualism, each the organisms gain from every other. When coevolution takes place amongst together reaping benefits species, it's far known as mutualistic coevolution.
Symbiotic relationships result in coevolution via way of means of growing reproductive blessings to organisms that optimize their courting with their symbionts. Pairwise coevolution (or 'specific' coevolution) describes tight coevolutionary relationships among species. Diffuse coevolution (or 'guild' coevolution) refers to reciprocal evolutionary responses among suites of species.
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when viewing a snp track for a gene, snps in the snp video were shown in black, blue, or red. which color is most common and why?
Blue color is most common SNPs happen when one nucleotide, or DNA's building block, is changed for another. These modifications may result in disease and may influence a person's response to germs, viruses, medications, and other substances.
SNP technique: what is it?Target sequences are scanned for novel polymorphisms and their alleles are identified using single nucleotide polymorphism (SNP) detection tools.
SNP chips are DNA microarrays used to analyse genetic variation at the many millions of unique places throughout the genome. 5 They were initially created to assess single nucleotide polymorphisms (SNPs) that are prevalent in the community and affect more than one in one hundred people.
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savannah is asked to explain the locations of the stages of cellular respiration. what location should she give for the site of the krebs cycle reactions?
What are the parts of the 3-component model for school-based agricultural education?.
These include leadership training, experiential learning, and classroom and laboratory education.
What does component, for instance, mean?Counting noun The parts that make up something are its constituents. One essential element of a nuclear bomb is enriched uranium. There are four basic parts to the management strategy. An alternative term for item is a portion. More the opposites of component.
A component at work is what?There are three parts to work: psychological, physical, and virtual. We go into further detail about the first one's importance in this blog. The psychological element refers to the demands and difficulties people face at work that have an impact on their performance.
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a person's blood pressure falls. which of the answer choices would you expect to occur? select all that apply.
A person's blood pressure may fall for a variety of reasons. Some common causes include dehydration, low blood sugar, and blood loss. If a person's blood pressure falls, they may experience dizziness, lightheadedness, or fainting.
When a person's blood pressure falls, the person's heart rate will usually increase in order to compensate for the lower blood pressure. The person may also feel dizzy or lightheaded due to the reduced blood flow to the brain. The person's skin may become clammy due to the reduced blood flow to the extremities. Shock is also a common example of blood pressure to drop. A person's heart rate would likely increase if their blood pressure fell.
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A. The person's heart rate will increase.
B. The person's blood vessels will constrict.
C. The person will feel dizzy or lightheaded.
D. The person will feel more alert.
E. The person's breathing will become shallow.
F. The person's skin will become clammy.
why are the vast majority of staphylococcus aureus isolates penicillin-resistant? group of answer choices they produce staphylokinase they produce coagulase they have loosely organized polysaccharide slime layers that protect their cell walls they have a coating of protein a they produce beta-lactamase
the vast majority of staphylococcus aureus isolates are penicillin-resistant because they produce beta-lactamase.
Penicillins are a class of β-lactam antibiotics that were originally isolated from P. chrysogenum and P. rubens molds. Using deep tank fermentation and subsequent purification, P. chrysogenum produces the majority of clinically used penicillins.
The β-lactamase-encoding gene blaZ plays a role in staphylococcal penicillin resistance. When staphylococci are exposed to β-lactam antibiotics, this mostly extracellular enzyme hydrolyzes the ring of the β-lactam, rendering it inactive. The antirepressor blaR1 and the repressor blaI, two adjacent regulatory genes, control blaZ.
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how should amazon be categorized? as a retailer, wholesaler, or broker? explain why (read chapter 8 for information).
Agents and brokers are the proper response.Agents and brokers are regarded as non-manufacturing traders because they enable trades by buying, selling, or even facilitating .
The things that they do not truly own or are not theirsIn plain English, a virtual retailer is one who conducts business exclusively online and does not deal with customers in a physical location like a shop or store.This is a contemporary business model where the company uses the internet to interact with a variety of clients. They frequently contract out other tasks, including order shipping, etc.A wholesaler is a person or business who sells things in bulk for a discount, usually to retailers.Those who sell things to the general public in comparatively modest quantities for use or consumption as opposed to resale are known as retailers.
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how could the botanist best determine whether the genotype of the green-pod plant is homozygous or heterozygous? view available hint(s)for part a how could the botanist best determine whether the genotype of the green-pod plant is homozygous or heterozygous? cross the green-pod plant with a yellow-pod plant. cross the green-pod plant with another green-pod plant. self-pollinate the green-pod plant.
The botanist can best determine whether the genotype of the green-pod plant is homozygous or heterozygous by crossing the green-pod plant with a yellow-pod plant.
An organism's complete set of genetic material is known as its genotype. The alleles or variants that a person carries in a particular gene or genetic location are also referred to as their "genotype."
It is known that the yellow-pod plant phenotype is homozygous recessive. For this situation, we would utilize a test cross to decide if there are any latent alleles in the unexplored world. Each offspring will have an allele for the recessive characteristic from the recessive homozygote (yellow-pod plant); the second allele (from the unknown genotype, green-pod plant) will determine the offspring's phenotype.
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what might trigger a prophage, or provirus, to become active and enter the lytic cycle?
The prophage/provirus is made active by environmental factors like heat, radiation, and certain chemicals. After removing itself from the DNA of the host cell, it
What components makes up DNA?The nucleotides that make up DNA are chemical building blocks. Phosphate groups, sugar groups, and one of four different nitrogen bases make up the three components that make up these building blocks. The phosphate and sugar groups in nucleotides bind together to create chains to make a DNA strand.
Why does DNA matter?When it comes to inheritance, protein coding, and providing instructions for life and its functions, DNA is a necessary component of all living things. A person's or an animal's development, reproduction, and eventual demise are all determined by their DNA. For a total of 46 chromosomes in each human cell, there are typically 23 pairs of chromosomes present.
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8
Use the model to answer questions 8 and 9.
For this question, choose THREE answers. Which of the following statements correctly describe the models?
Both processes take place in eukaryotic cells
Both processes produce identical daughter cells
Both processes involve no replication
Both processes involve separation of chromosomes
Both processes involve copying the DNA
The three statements that depict the diagram are Both processes produce identical daughter cells, both processes involve the separation of chromosomes, and both processes involve copying the DNA.
What happens in equational cell division?
There are two types of cell division: equational, in which the daughter cell has the same genetic content as the parent, and reductional, in which the genetic content of the daughter cell is half that of the parent. The diagram explains binary fission and mitosis, where both produce similar cells by segregation of chromosomes.
hence, The three statements that depict the diagram are Both processes produce identical daughter cells, both processes involve the separation of chromosomes, and both processes involve copying the DNA.
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a cell biologist determines that diploid cells from a particular species of grasshopper contain 200 picograms of dna per cell during the g2 stage of interphase. based on this finding, how many picograms of dna should be present in a single cell from this species during metaphase i of meiosis?
There are 8 picograms of DNA that should be present in a single cell from this species during metaphase I of meiosis.
At the end of mitosis, the two daughter cells are exact copies of the original cell. Each daughter cell has 30 chromosomes. At the end of meiosis II, each cell has half the original number of chromosomes, or 15. The chromatids double but the number of chromosomes remains the same.
G2 has 12 chromosomes and 24 chromatids. There are 46 chromosomes in metaphase, each composed of two sister chromatids that align with the metaphase plate. Then, during anaphase, these chromatids are separated and attracted to opposite poles of the cell. This segregation gives rise to 92 separate chromatids within the cell considered 92 chromosomes.
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for na -k pump, a) is it a primary or a secondary active transport system? b) how many na get transported out? how many k get transport in? c) how much energy is involved in one cycle of the transport? d) what is the main function of the pump?
Na-K pump is a primary active transport system that transports 3 Na⁺ outside the cell and 2 K⁺ inside the cell. In one cycle a ATP is required through which 3 Na⁺ and 2 K⁺ are moved. The main function of the Na⁺-K⁺ pump is to maintain the osmotic balance as well as the membrane potential of the cells.
Osmotic balance is defined as the balance of salt and water inside the body. The phenomenon is also known by the name osmoregulation. Electrolytes play an essential role in the maintenance of osmotic balance.
Membrane potential is the difference in the voltage between the inside and the outside of the cell. The membrane potential is at rest when the inside of the cell is negative as compared to the outside.
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recall the basic structure of blood vessels in the placenta: how does it contribute to the fetus' problem of getting sufficient o2?
The organs in the lower half of the embryonic body receive oxygen-poor blood via the ductus arteriosus. This permits the blood that is deficient in oxygen to leave the foetus and return to the placenta, where it can pick up oxygen.
An organ that grows in the uterus during pregnancy is the placenta. A developing newborn receives oxygen and nutrients from this structure. It also cleans the baby's blood of waste materials. The baby's umbilical cord grows from the placenta, which is attached to the uterus' wall throughout pregnancy. The placenta of the mother and the newborn are connected through the umbilical chord. The umbilical cord serves as the baby's lifeline during foetal growth in the womb by delivering nutrients. The cord is pinched and cut after delivery. The cord will eventually become dry and fall off naturally after 1 to 3 weeks.
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A cell undergoing meiosis experiences a problem with its microtubules, such that proper separation of the paired chromosomes carrying alleles q and q does not occur during anaphase i. What is the most likely effect on the four daughter cells?.
The maximum probable effect at the 4 daughter cells is as follows i.e., all 4 daughter cells could have a complete chromosome set besides daughter cells could have one greater chromosome that carries the Q or q allele, and the alternative daughter cells could be lacking the chromosome that carries the Q or q allele.
Likewise, bizarre separation can arise in meiosis while homologous pairs fail to split for the duration of anaphase I. This additionally outcomes in daughter cells with extraordinary numbers of chromosomes. The phenomenon of unequal separation in meiosis is known as nondisjunction. In the primary nuclear division, homologous chromosomes segregate (reductional mobileular division), and withinside the 2nd one, sister chromatids segregate (equational mobileular division).
As such, every daughter mobileular includes 1/2 of the quantity of the parental genetic material. q = frequency of the recessive allele withinside the population. p2 = percent of homozygous dominant individuals.= percent of homozygous recessive individuals. 2pq = percent of heterozygous individuals
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What unusually biodiverse island is home to the dragon blood tree, which appears to bleed when cut?.
Biodiverse island that is home to the dragon blood tree which appears to bleed when cut is : Socotra.
What happens when dragon blood tree is cut?When the dragon blood tree is cut, it releases a red sap or resin, that is known as dragon blood. If you cut this tree then the red resin will seep out, giving an impression of bleeding
The dragon blood tree has an unique appearance, with an upturned, densely packed crown having the shape of an umbrella. This species is named after its dark red resin, which is known as dragon's blood.
Even if the branch break, blood starts coming out of them, which is a dark red liquid that just appears like blood.
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When there is decreased blood supply to the coronary arteries, which tissue of the heart is affected first?.
Narrowed arteries can obstruct blood flow to your heart muscle and the rest of your body, narrowed arteries can lead to chest pain. CAD can weaken the heart muscle over time.
The heart muscle receives blood from the coronary arteries. The heart muscle needs oxygen-rich blood in order to operate, just like all other bodily components do. Blood that lacks oxygen must also be transported away. Outside of the heart, the coronary arteries encircle the organ. Coronary artery disease may cause coronary blood flow to be decreased. As a result, there will be a greater extraction of oxygen from the coronary blood and less oxygen in the veins. Angina and tissue hypoxia result from this
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all cells use _______ energy carried by ATP
Answer:
molecule
Explanation:
food molecules
which processes lead to most genetic variation in sexually reproducing organisms?select all that apply.which processes lead to most genetic variation in sexually reproducing organisms?select all that apply.random fertilizationcytokinesiscrossing overindependent assortment of chromosomes in meiosis
Most genetic variation occurs due to random fertilization, crossing over, and independent assortment in meiosis.
What is genetic variation?Crossing over is the mechanism that causes the most genetic variation in sexually reproducing organisms.
New allele combinations are produced via independent assortment crossover occurs when two non-sister chromatids exchange specific DNA segments, and random fertilization improves genetic variety.
Therefore due to the independent assortment of chromosomes in meiosis crossing over and random fertilization creates the most genetic variation.
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how do ecologists define a community? it depends on what the scientist is specifically interested in studying. as a group of species interacting with the non-living factors of the environment and with one another. all of the individuals of a particular species. the relative abundance of a species.
A community is a collection of species that dwell in a certain area, according to ecologists.
What exactly do ecologists do?From the complicated interplay between the dozens of plant, animal, as well as other species found in a desert to the study of minuscule bacteria thriving in a fish tank, ecologists examine these links between species and ecosystems of many various sizes. Environmental scientists research a variety of habitats.
Who made the ecologist's name?The College of Georgia honors Eugene Odum as the creator of what is now the Eugene P. Sloan Foundation and is widely regarded as that of the pioneer of modern ecology.
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g which fossil provides an example of controlled biomineralization? before the appearance of complex animal life in the fossil record
An organic matrix or soluble biomolecules, combined with locally generated biological conditions, enable the crystallization of minerals and regulate their morphologies and sites of nucleation during a process known as biomineralization.
The discovery which dates to around 809 million years ago is the earliest example of an organism directing the process of biomineralization, in which minerals are formed.
Living things create minerals through a process called biomineralization, which is frequently used to harden already-existing tissues. The production of bone, teeth and animal exoskeletons depends critically on natural biomineralization processes, about which a great deal of knowledge has been gained in recent years.
When the metabolic activity of microbes creates chemical conditions that are conducive to the mineral formation, biologically induced mineralization takes place.
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Suppose that for a certain gene, nearly 100 percent of the normal level of expression is required to produce the normal phenotype. Based on this requirement, one could predict that a _________ mutation would be _________.
Based on this requirement, one could predict that a loss of function mutation would be dominant.
What is mutation?
Mutations are changes that occur in DNA sequence, due to mistakes during replication or environmental factors. Mutations may lead to changes in proteins that are translated by DNA. The cells can usually identify any damage caused by mutations and immediately repair it.
Mutations are sudden modifications in an organism’s traits that are also heritable. Recessive genes are usually produced by mutations.
Mutations often lead to genetic variation in species. Successive generations receive positive mutations.
Mutations mostly occur due to internal causes such as some mistake during DNA replication. All mutations of these kind lead to evolution.
External mutations are usually due to the DNA being exposed to some chemicals or radiations, causing breakdown of DNA.
Therefore, one could predict that a loss of function mutation would be dominant.
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Which statement is NOT correct about glycolysis?
Glycolysis occurs in both aerobic and anaerobic respiration.
During glycolysis, glucose is produced.
Glycolysis uses two ATP but forms four ATP, resulting in a net gain of two ATP molecules.
Glycolysis involves splitting the glucose into 2 pyruvate molecules
The statement during glycolysis, glucose is produced is NOT correct about glycolysis (Option B).
What is the glycolysis metabolic pathway?The glycolysis metabolic pathway is a process in which glucose molecules are broken in order to release energy, which is used in the cell to create ATP from ADP and phosphate, being ATP the energy coin of the cells.
Therefore, with this data, we can see that the glycolysis metabolic pathway is a chemical process that is well known to generate ATP by breaking down glucose molecules instead of generating simple carbohydrates.
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in which direction does fluid move across the capillary wall at the arterial end of the capillary, in the situation described?
In general, fluid enters the interstitial fluid from the capillary. This method is known as filtering.
Like all fluids, blood moves from an area of high pressure to one of low pressure. As the pressure gradient decreases, blood moves from arteries through capillaries and veins in the same direction.Diffusion, the transfer of molecules from places of high pressure to low pressure, exchanges fluids when blood travels from arteries to veins through the capillary bed.Fluids and tiny molecules will be forced through the capillary's pores and openings by the hydrostatic pressure of the blood. Because the hydrostatic pressure inside the capillary is greater than the hydrostatic pressure outside it at the arteriole end, there is a net movement of materials outside the capillary.
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describe the process of audition, following a sound wave from the outer ear through the middle ear and into the inner ear. how are auditory neurons ultimately activated?
Sound waves enter the external ear and travel through a restricted path called the ear channel which prompts the eardrum. The eardrum vibrates from the approaching sound waves and sends these vibrations to three little bones in the center ear.
These bones are known as the malleus incus and stapes. The bones in the center ear enhance, or increment, the sound vibrations and send them to the cochlea, a snail-formed structure loaded up with liquid, in the internal ear. A versatile segment runs from the very start to the furthest limit of the cochlea, parting it into an upper and lower part.
This parcel is known as the basilar film since it fills in as the base, or ground floor, on which key hearing designs sit. When the vibrations make the liquid inside the cochlea swell, a voyaging wave structures along the basilar film. Hair cells tangible cells sitting on top of the basilar layer ride the wave. Hair cells close to the wide finish of the snail-molded cochlea identify more shrill sounds, for example, a newborn child crying. Those nearer to the middle distinguish lower-pitched sounds for example a huge canine yelping.
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Hearing, or audition, is the transduction of sound waves into a neural sign this is made viable by the structures of the ear The big, fleshy shape on the lateral thing of the head is referred to as the auricle.
The incoming sound waves motivate the eardrum to vibrate. The eardrum sends those vibrations to the 3 tiny bones in the middle ear known as the malleus, incus, and stapes. The bones inside the center ear expand, or growth, the sound vibrations and ship them to the cochlea within the internal ear.
Sound is transduced into neural signals in the cochlear region of the internal ear, which incorporates the sensory neurons of the spiral ganglia. these ganglia are positioned inside the spiral-shaped cochlea of the inner ear. The cochlea is attached to the stapes thru the oval window.
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