Answer:
Desert plants are subjected to high temperatures and scarcity of water. To prevent the loss of water through transpiration or evaporation desert plants have leaf modified into spines and the epidermis is covered with a thick waxy coating
about one-half of leukocytes are __________.
About one-half of leukocytes are Neutrophils.
In humans, neutrophils (one half of the leukocytes), also known as neutrocytes or heterophils, comprise up 40% to 70% of all white blood cells and are the most prevalent form of granulocyte. They are a crucial component of the innate immune system, and depending on the species, they serve varied purposes.
Neutrophil-killer and neutrophil-cager subpopulations are differentiated from stem cells that are produced in the bone marrow. They have a short lifespan and are very mobile because they may access tissues that other cells or chemicals cannot. Segmented neutrophils and banded neutrophils are two types of neutrophils (or bands). They are a member of the family of polymorphonuclear cells (PMNs), along with basophils and eosinophils.
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A B cell is first stimulated by ______.free antigenantigen presented on an MHC class I molecule of an infected cellantigen presented on an MHC class II molecule of an APCantigen presented on an MHC class I molecule of an APC
Antigen presented on a MHC class II molecule. The antigen is delivered by the B-cell antigen receptor to intracellular locations, where it is broken down.
Sent back to the surface of the B-cell as peptides attached to MHC class II molecules. Armed helper T cells that are specific for an antigen can recognise the peptide: MHC class II complex, inducing them to produce proteins that cause the B cell to multiply and its offspring to develop into cells that secrete antibodies. In the absence of assistance from T cells, some microbial antigens can directly activate B cells. Many significant bacterial infections can be quickly responded to thanks to the B lymphocytes capacity to react directly to these antigens. However, the interaction of antigen-stimulated B cells with helper T cells and other cells is necessary for somatic hypermutation and switching to specific immunoglobulin isotypes.
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When adenine base pairs with thymine hydrogen bonds form and when cytosine base pairs with guanine hydrogen bonds form?
Adenine and Thymine invariably base pair with Cytosine and Guanine in DNA. These pairings take place because of the geometry of the bases, which only permits hydrogen bonds to form between certain pairs. While cytosine and guanine will make three hydrogen bonds, adenine and thymine will only form two.
Only in DNA may adenine and thymine be paired as bases. The two nitrogenous bases are joined by two hydrogen bonds. One of the hydrogen bonds is created between the oxygen atom of the keto group at C-4 of thymine and one of the amino group's hydrogen atoms at C-6 of adenine.
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What are two risk factors that can be modified by lifestyle changes to reduce the risk of heart disease?
The two most important risk factors which can be modified to reduce risk of heart diseases are reducing the smoking rate and avoiding excessive junk food.
Heart diseases are those which affect the functioning of heart such as ability to pump blood properly or generation of electrical signals inside the heart so that the cardiac cycle can be continued smoothly. Risk factors are those conditions which affect the chances of diseases being worse with time. Heart is related to lungs almost directly as pulmonary system and cardiovascular system work in coordination with each other.
Excessive smoking causes damage to bronchioles and lungs due to suffocation and settling of harmful particulate matter inside the lungs. Similarly, excessive junk food chokes the heart muscles and arteries due to accumulation of cholesterol and fat. Lack of physical exercise is also one of the cause. Alcohol consumption, stress and anxiety and opium consumption is also disastrous for heart.
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What are the 2 main processes that occur during meiosis that explain why there is so much diversity between individuals of the same family and within the same species?
Genetic recombination via Crossing over and independent assortment of gametes are the 2 main processes that occur during meiosis that explain why there is so much diversity between individuals of the same family and within the same species.
The physical breakage, exchange, and rejoining of two DNA molecules is known as genetic recombination. In bacteria, several different pathways can mediate homologous or general recombination. RecA protein is required for each of these pathways to align the DNA molecules between regions of significant DNA sequence identity.
Crossing over is a cellular process that occurs when identical chromosomes line up during meiosis. Parts of the chromosome can be switched when two chromosomes — one from each parent — line up. The same genes may exist on both chromosomes, but in different forms.
Alleles from two (or more) different genes are sorted into gametes independently of one another, according to Mendel's law of independent assortment. In other words, a gamete's allele for one gene has no effect on the allele received for another.
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What is used for chemical symbols?
Most chemical elements are represented symbolically by letters, generally the first two in their name.
An element symbol is a type of shorthand for representing an element. A chemical symbol is a letter or combination of characters that represents a chemical element.
Chemical symbols and element symbols are used interchangeably. A chemical symbol is analogous to an abbreviation; for example, a doctor would write MD after her name to indicate that she is a doctor of medicine.
Because it is shorter and easier to write, the chemical symbol for an element is used when expressing the chemical formula for a molecule or when formulating a chemical equation. A subscript may be used in conjunction with the symbol to indicate the presence of more than one atom of that element.
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What is insertion and deletion in mutation?
Indels, or insertion–deletion mutations, are events with a length of less than 1 kilobase point that occur in genomic DNA.
An organism's DNA sequence is altered by a mutation. Errors in DNA replication during cell division, exposure to mutagens, or a viral infection can all cause mutations.
By inserting one or more nucleotides into the gene, an insertion alters the DNA sequence. Accordingly, the protein produced using the quality may not work as expected. Deletion. By removing at least one nucleotide from a gene, a deletion alters the DNA sequence. One or a few nucleotides are deleted from a gene by small deletions, while an entire gene or several neighboring genes can be deleted by larger deletions. The affected protein or proteins' function may be altered by the deleted DNA.
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What are the 4 steps of the carbon cycle?
Respiration, combustion, decomposition, and photosynthesis. Carbon enters plants and other living things through the atmosphere.
Using light energy, plants and some other organisms engage in a process known as photosynthesis that results in the creation of oxygen and high-energy carbohydrates like sugars and starches.
Respiration is the process by which a living thing or cell absorbs oxygen from the atmosphere or water, disperses it for oxidation, uses it, and releases products of oxidation.
Combustion is the process of burning fuels to create heat and light.
Decomposition is the disintegration of organic material
Which 4 spheres make up the carbon cycle?In all four of the planet's major spheres—the biosphere, atmosphere, hydrosphere, and lithosphere—carbon is a very prevalent element.
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FILL IN THE BLANK. primates known as anthropoids include all of the following groups except ________.
The primates called anthropoids include all of the given organisms except: (A) lemurs.
The term anthropoids refers to the living organisms that belong to the infra-order Anthropoidea of the order Primates. These are also known by the name simians. Anthropoids in simpler terms refers to 'man-like'. The example of organisms belonging to this are: humans, apes, Hominini, etc.
Lemurs are the mammals that belongs to the family Lemuridae of the order Primates. Lemurs are native to the island of Madagascar. The characteristics of lemurs are: small and pointed snout, large eyes, and a long tail. They are called the wet-nosed primates.
The given question is incomplete, the complete question is:
Primates known as anthropoids include all of the following groups except ________.
(A) lemurs
(B) Old World monkeys
(C) New World monkeys
(D) humans
(E) gorillas
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How many phenotypes are possible with 4 alleles?
We all have alleles, or versions, of every gene. Being homozygous for a selected gene approach you inherited equal versions many phenotypes are possible with 4 alleles are 16.
It's the alternative of a heterozygous genotype, in which the alleles are distinct. People who've recessive traits, like blue eyes or purple hair, are continually homozygous for that geneAlleles make contributions to the organism's phenotype, that is the outward look of the organism. Some alleles are dominant or recessive.
When an organism is heterozygous at a selected locus and includes one dominant and one recessive allele, the organism will explicit the dominant phenotype.Since every figure has 4 distinct combos of alleles withinside the gametes, there are 16 feasible combos for this cross.
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specific adaptations that animals have developed to survive in humid subtropical climates
Answer:
Animals that live in humid subtropical climates have developed a variety of adaptations to help them survive and thrive in these conditions. Some examples of these adaptations include:
:Thick, insulating fur or feathers: Many animals in humid subtropical climates have thick fur or feathers that help to keep them warm and dry in wet conditions. This can help to prevent heat loss and maintain body temperature, which is especially important in environments where the air is cool and damp.
:Waterproof skin or scales: Many animals in humid subtropical climates have skin or scales that are waterproof or water-repellent. This helps to prevent them from getting waterlogged and can make it easier for them to move through wet environments.
:Webbed feet or other adaptations for swimming: Some animals in humid subtropical climates, such as amphibians and aquatic mammals, have webbed feet or other adaptations that allow them to swim efficiently. This can help them to move through wet environments and avoid predators.
:Behavior patterns that minimize exposure to heat and moisture: Many animals in humid subtropical climates have behavior patterns that help them to avoid the heat and moisture that can be common in these environments. For example, some animals may become inactive during the hottest parts of the day, or may seek shelter in cool, damp areas during times of extreme heat or moisture.
:Specialized digestive systems: Some animals in humid subtropical climates have specialized digestive systems that allow them to extract nutrients from wet or damp foods, such as grasses and leaves. This can help them to survive in environments where food may be scarce or difficult to access.
Overall, the specific adaptations that animals have developed to survive in humid subtropical climates vary depending on the species and the specific conditions of the environment. However, these adaptations generally help animals to regulate their body temperature, move efficiently through wet environments, and access food and other resources in these conditions.
Explanation:
Explain what is happening at each numbered step in the diagram below
Steps are in protein synthesis:
1) m-RNA
2) ribosome / r-RNA
3) amino acid
4) t-RNA
5) peptide linkage.
What is protein sysnthesis?The cytoplasm contains ribonucleoprotein particles called ribosomes, which are where protein synthesis takes place. In biology, the process of protein synthesis is crucial to cellular survival. The process through which cells produce proteins is known as protein synthesis.
Function of these steps in protein synthesis -
1) m-RNA : The function of mRNA is to transport protein information from DNA in a cell's nucleus to the cytoplasm, or watery interior, where the machinery responsible for making proteins reads the mRNA sequence and converts each three-base codon into an amino acid that belongs in a protein chain that is expanding.
2) ribosome / r-RNA: The catalytic stages of protein synthesis—the joining of amino acids to form a protein molecule—are governed by the rRNA molecules. To represent this role, rRNA is frequently referred to as a ribozyme or catalytic RNA.
3) amino acid: Long thought to as little more than protein synthesis substrates, amino acids have lately been demonstrated to operate as modulators of intracellular signal transduction pathways frequently linked to growth-promoting hormones like insulin and insulin-like growth factor1.
4) t-RNA: The primary role of tRNA is to transfer amino acids to create polypeptides in the proper order. As a result, it aids in protein synthesis. Additionally, it serves as an adaptor molecule by connecting particular amino acids to the appropriate codons found in the mRNA molecules.
5) peptide linkage: Covalent bonds between two amino acids are known as peptide bonds. Proteins are large chains of amino acids that are created by living things via peptide bonds. In addition to providing structural support, initiating significant processes, and identifying chemicals in the environment, proteins have a variety of other activities.
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What factors can influence the rate of transport in cell membrane?
Answer:
the mass of the solute, the temperature of the environment, the solvent density, and the distance traveled.
How many phenotypes are possible with 8 alleles?
There are 36 feasible phenotypes and genotype for the are possible with 8 alleles for an autosomal gene with eight alleles.
Examples of phenotypes encompass top, wing length, and hair color. Phenotypes additionally encompass observable traits that may be measured withinside the laboratory, consisting of ranges of hormones or blood cells.
Phenotype" really refers to an observable trait. "Pheno" really means "observe" and springs from the equal root because the word "phenomenon". And so it is an observable kind of an organism, and it may seek advice from whatever from a not unusualplace trait, consisting of top or hair color, to presence or absence of a disease.
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You find a soldier lying face down. The soldier is conscious and tells you that he thinks he has injured his back. What should you do? select the best answer.
A soldier lying face down with injuries his back injured must be handle with proper care and at the earliest. First of all I will look for the place at his back where he was injured and how much he was injured. And then very carefully lift him up and will look for a stretcher or gurneys and will look out for some help. I will try to arrange some vehicle and rush him to the nearest medical care.
80 percent of transmission fluid is: _________
a. Lubricating oil
b. Detergents
c. Dispersants
d. Friction modifiers
Lubricant oil comprises 80% of transmission fluid.
A family of lubricants known as lubricating oil, sometimes known as lubricant or lube, is used to lessen wear, heat, and friction between mechanical components that are in touch with one another. Motor oil and transmission fluid are two specific names for lubricating oil, which is used in motorised vehicles. Vegetable-derived materials are preferable for lubricant base oil application. High oleic canola oil, castor oil, palm oil, sunflower seed oil, rapeseed oil, and tall oil from tree sources are examples of common ones. Oil-based, water-based, and silicone-based lubricants are the three main categories.
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Can a recessive gene become dominant?
The specific DNA difference that causes the trait is what makes it recessive. So one way for a trait to progress from recessive to dominant is for a new dominant DNA difference that causes the same trait to arise.
What factors contribute to a gene's dominance?A dominant relationship exists between two versions of a gene. Individuals inherit two copies of each gene from each parent, which are referred to as alleles. Only one allele of a gene will be expressed if two alleles differ; this is the dominant gene. The effect of the other, recessive allele is obscured.
How recessive genes are passed down to future generations?Because recessive inheritance necessitates the abnormality of both genes in a pair for disease to occur. Carriers are individuals who only have one of the two defective genes. These people are frequently oblivious to the condition. However, they can pass on the abnormal gene to their children.
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If the partial pressure of oxygen in both air and water is 100 mm hg, then the concentration of the oxygen is the same in the air and water.
a. true
b. false
If the partial pressure of oxygen in both air and water is 100 mm Hg, then the concentration of the oxygen is the same in the air and water. This statement is False.
A gas's partial pressure is the force it exerts. The sum of the partial pressures in a gas mixture equals the overall pressure. When forecasting gas flow, partial friction is extremely important. Remember that gases in two connected regions tend to equalize their pressure.
The arterial blood gas is the primary method for determining the partial pressure of oxygen.
This provides a direct measurement of the partial pressure of oxygen, the partial pressure of carbon dioxide, acidity (pH), oxyhemoglobin saturation,and bicarbonate concentration in arterial blood.
The sum of the partial pressures of the gases in an ideal gas mixture is the total pressure. A gas's partial pressure is a measure of the thermodynamic activity of its molecules.
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What is a germline cell?
A model of natural selection is shown here with a small beetle population. Some green beetles in the original population are shown as dying by predation. The resulting population several generations later is shown on the right. Which of these explanations should be selected to account for the changes in the population of beetles shown here?
The explanation which should be selected to account for the changes in the population of beetles in this scenario is that beetles with brown coloration survived with greater frequency in the original population, resulting in a greater frequency of brown beetles in subsequent populations which is therefore denoted as option D.
What is Population?This is referred to as the total number of organisms which are present in an area over a given period of time and is dependent on various factors such as environment etc.
In this scenario, beetles with brown coloration survived with greater frequency in the original population. This therefore led to them undergoing reproduction with the others who have such color in the ecosystem.
The result will therefore be a greater frequency of brown beetles in subsequent populations due to it being a dominant color thereby making it the correct choice.
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The options are:
A) Individual green beetles evolved to be less adapted, resulting in a change in allele frequencies in future generations.
B) Individual brown beetles evolved in the presence of the predator to be better adapted, making it more common in future generations.
C) Green beetles that survived the presence of the predator migrated to different populations, decreasing their frequency in the subsequent populations.
D) Beetles with brown coloration survived with greater frequency in the original population, resulting in a greater frequency of brown beetles in subsequent populations
How many genes make up the human genome four adenine thymine guanine and cytosine 23 pairs of genes 20000 25000 genes billion genes?
Genes are the hereditary units, which are present in the coded segments of the DNA. Genes carry the information from parent to daughter cells.
There are 20,000 to 25,000 genes that make up the human genome.
Human Genome Project was conducted for several years, the result obtained was:
The human genome project was an international scientific project, which aimed at determining the base pairs that make up the human DNA.
The project estimated that humans consist of 20,000 to 25,000 genes in their genome. Each individual inherits the copies of genes from both parents.
Therefore, the correct answer is Option C.
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Which three statements correctly describe the processing that takes place before a mature mRNA exits the nucleus?
A. Noncoding sequences called introns are spliced out by molecular complexes called spliceosomes.
B. A translation stop codon is added at the 3' end of the pre-mRNA.
C. A cap consisting of a modified guanine nucleotide is added to the 5' end of the pre-mRNA.
D. A poly-A tail (50-250 adenine nucleotides) is added to the 3' end of the pre-mRNA.
E. Coding sequences called exons are spliced out by ribosomes.
The processing that takes place before a mature mRNA exits the nucleus,
A translation stop codon is introduced to the pre-mRNA's 3' end.
c. The 3' end of the pre-mRNA gets a poly-A tail (50–250 adenine nucleotides) attached to it.
d. Ribosomes splice out coding segments referred to as exons.
In eukaryotes, RNA must leave the nucleus through the nuclear membrane's pores and reach the cytoplasm to undergo translation during protein synthesis. The 3' Poly-A tail, 5' capping, and pre-mRNA splicing are the mRNA's departure mechanisms.The 5'capping procedure involves adding a 7-methylguanosine cap through phosphate linkage to the 5' end of the mRNA. This procedure helps to start translation processes and prevents mRNA degradation.The cleaving of pre-mRNA and attachment of about 200 A nucleotides, or the 3'poly (A) tail, to the mRNA by the poly (A) polymerase enzyme protein complex is known as the 3' Poly-A tail step. This facilitates the transfer of mRNA to the cytoplasm, stops pre-mRNA degradation, and starts translation.
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The _______ is the part of the digestive tract that has the most lymph nodules and bacteria.
A. duodenum
B. jejunum
C. ileum
D. colon
The part of the digestive tract that has the most lymph nodules and bacteria is the ileum, which is present in Option C, and the gut bacteria play an important role in digestion.
What is the importance of the ileum in digestion?The small intestine is important in digestion because it contains the duodenum, jejunum, and ileum, with the ileum being highly folded to facilitate digestion and absorption rates into the blood; additionally, there are many gut bacteria that aid in digestion.
Hence, the part of the digestive tract that has the most lymph nodules and bacteria is the ileum, which is present in Option C, and the gut bacteria play an important role in digestion.
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explain where. in the world. the hbs allele is mostly likely to be prevalent and why the allele persists in spite of the danger associated with having two hbs alleles
The hbs allele is most likely to be common in regions with high rates of malaria like African area. The heterozygotes are not negatively impacted and are provided a benefit in these areas, therefore the allele survives.
What does the Hbs allele correspond to?Sickle cell anemia, which develops when two copies of the Hbs allele are inherited, is a serious, chronic condition that can be fatal. Hemoglobin becomes aberrant as a result, forcing the red blood cell to assume a crescent-shaped form and becoming hard as opposed to flexible. The red blood cell's shape is slightly altered by inheriting one copy of the Hbs allele (becoming a carrier), but not significantly enough to impair function as in the full disorder.For more information on Hbs allele kindly visit to
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Which of the following is the best explanation for presence of both chloroplasts and mitochondria in plant cells?
A. In the light, plants are photosynthetic autotrophs. In the dark, they are heterotrophs
B. If plants cannot produce enough ATP in the process of photosynthesis to meet their energy needs, they can produce it in aerobic respiration
C.Sugars are produced in chloroplasts. These sugars can be stored in the plant for later use, converted to other chemicals, or broken down in aerobic respiration to yield ATP for the plant to use to meet its energy needs.
D. The leaves and sometimes the stems of the plants contain chloroplasts which produce ATP to meet the energy needs of these plant parts. The roots of plants contain mitochondria which produce ATP to meet the energy needs of these plants.
Answer:
Plant cells require both chloroplasts and mitochondria since they carry out both cell respiration and photosynthesis.
Explanation:
Which of the following are reasons why eukaryotes have a more complex gene regulation than prokaryotes?
a. Eukaryotic DNA is organized into chromatin.
b. In eukaryotes, transcription occurs in the nucleus, while translation occurs in the cytoplasm.
The correct option b. In eukaryotes, transcription occurs in the nucleus, while translation occurs in the cytoplasm are reasons why eukaryotes have a more complex gene regulation than prokaryotes.
Most eukaryotes have larger, more complex genomes than prokaryotes do. Since more genes are often found in more complex species, the larger size of eukaryotic genomes is not a major surprise. The size of many eukaryotes' genomes, however, does not seem to be correlated with their genetic complexity.For instance, while having genomes that are more than ten times as large as those of humans and salamanders, respectively, these creatures are unquestionably not ten times as complicated than ourselves.
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explain how selective breeding can use gentic trait mutations
Answer:
Selective breeding involves choosing parents with particular characteristics to breed together and produce offspring with more desirable characteristics. Humans have selectively bred plants and animals for thousands of years including: crop plants with better yields.
Explanation:
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__________ evolution leads to __________ structures.
Convergent, analogous. If two species from separate evolution branches have comparable ecological functions and natural selection has sculpted parallel adaptations, they may start to resemble.
Analogous structures demonstrate that comparable selection forces might result in similar adaptations with advantageous traits, whereas homologous structures demonstrate evidence for shared ancestry. The relatedness of different species can be ascertained by comparing and contrasting biological molecules, such as the DNA sequence of genes.
Natural selection, genetic drift, gene flow, and mutation are the four driving forces behind evolution. In a gene pool, mutation produces new genetic variety. A population's genetic makeup evolves throughout time as a result of the process of evolution. Genes can change as a result of an organism's adaptation to its environment, which is reflected in evolution.
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Because older adults are more prone to injury, exercise programs: __________
Because older adults are more prone to injury, exercise programs Should focus on low impact aerobic approaches
Injury-prone is defined as "frequently injured or frequently sustaining injuries" by dictionaries. When people say "injury-prone," they usually mean someone with a history of injuries. The phrase itself is unconcerned with the types of injuries or the causes of them. Low-impact exercises require you to lift at least one foot off the ground. Cycling, elliptical machine cardio, hiking, yoga, Pilates, and dancing are a few examples. These exercises are gentler on the joints and muscles because they have less impact. Low-impact exercises also provide a gentle workout on easy days and can help with recovery on difficult days. High-impact exercises are on the other end of the spectrum. These exercises are hard on the joints.
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Select the correct term. The sciatic nerve divides into the tibial and POSTERIOR FEMORAL CUTANEOUS / COMMON FIBULAR nerve.
The sciatic nerve divides into the tibial and COMMON FIBULAR nerve.
Leg discomfort, weakened sensation, numbness, or tingling are all symptoms of sciatica. The sciatic nerve is harmed or put under pressure, which causes it. Sciatica is a sign of a health issue. By itself, it does not constitute a medical condition.
When the sciatic nerve is squeezed, sciatica develops. A herniated disc in the spine or an expansion of bone, commonly referred to as bone spurs, on the spinal bones are the usual causes. Occasionally, a tumour may irritate the nerve. Alternatively, a condition like diabetes can harm the nerve.
A significant nerve that innervates the lower extremity is the common peroneal nerve, commonly referred to as the common fibular nerve. It gets fibres from the posterior divisions of L4 through S2 and is one of the sciatic nerve's two main branches.
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