True. Viruses do not have nucleus or a cell.
Explain viruses.A virus is a contagious particle that multiplies by "commandeering" a host cell and exploiting that cell's resources to create further viruses. A virus is composed of a DNA or RNA genome enclosed in a capsid, a protein shell. Viruses come in a wide variety. They have various genome types, distinct forms and architectures, and they infect various hosts. Since viruses lack the cytoplasm, organelles, and nuclei that cells do, they are unable to monitor or influence their internal environment. By infecting their host cells and reprogramming them to become virus-producing "factories," viruses spread throughout the body.
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True. Viruses do not have nucleus or a cell.
What is Virus?A virus is a type of malicious software that infects computers and other devices connected to the internet. It is designed to spread from one computer to another, often without the user's knowledge or permission. Once a virus is on a device, it can cause damage by deleting files, corrupting data, or by taking control of the device and using it to spread itself to other devices. In some cases, a virus can also allow a hacker to gain access to the device and use it to steal personal information or perform other malicious actions. To prevent virus infections, it is important to keep all software, including the operating system, up to date and use antivirus software to scan incoming files and emails.
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which theory suggests that aging is the result of unstable oxygen molecules that cause damage to the structure of cells with age? wear-and-tear theory cellular clock theory disengagement theory free radical theory senescence theory
Free extreme hypothesis recommends that maturing is the after-effect of unsound oxygen particles, known as free revolutionaries, that cause harm to the design of cells with age.
Free revolutionaries begin from typical natural cycles like breathing or digestion, as well as outside elements like contamination or bright radiation.
These atoms are profoundly receptive, and when they come into contact with different particles inside cells, they harm or modify the cell's design, prompting the impact of maturing.
The free extreme hypothesis is upheld by research that has laid out a connection between free extreme harm and the maturing system.
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which type of molecule is more likely to quickly pass through a cellular membrane via simple diffusion, polar or non-polar? why? (you may need to use information from your textbook and class discussions to answer this question.)
Because non-polar molecules are soluble in non-polar phospholipid tails, they diffuse more easily than polar molecules.
Polarity is a separation of electric charge in chemistry that results in an electric dipole moment with a negatively charged end and a positively charged end in a molecule or its chemical groups.
Because of the difference in electronegativity between the bound atoms, polar molecules must have one or more polar bonds. If the bond dipoles cancel each other out through symmetry, molecules with polar bonds have no molecular polarity.
Polar molecules communicate with one another via dipole-dipole intermolecular interactions and hydrogen bonds. A multitude of physical characteristics, such as surface tension, solubility, and melting and boiling temperatures, are influenced by polarity.
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alcohol fermentation and aerobic respiration are similar in that both processes_____
Alcohol fermentation and aerobic respiration are similar in that both processes glycolysis.
Alcoholic fermentation and aerobic respiration both use glycolysis to generate a net gain of two ATP molecules.
Glycolysis is an anaerobic (without oxygen) mechanism that muscles use to obtain the majority of their energy during hard or extended activity. A very similar process known as alcoholic fermentation is used by yeast cells to obtain energy in anaerobic environments. The chemical conversion of glucose to lactic acid is known as glycolysis. Through this process, adenosine triphosphate, a high-energy phosphate molecule, becomes available for use by cells as energy (ATP). The only difference between glycolysis and alcoholic fermentation is the last step. Pyruvic acid is converted into ethanol and carbon dioxide during the alcoholic fermentation process. The byproducts of alcoholic fermentation have been utilized in baking and brewing for ages, lactic acid from glycolysis causes fatigue.
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Read the article and use the information to answer the question that follows.
Methods of Classification
Name and describe the three methods of classification used to construct a phylogenetic tree.
Phylogenetic trees are used in evolutionary biology to show and demonstrate the evolutionary links between two or more creatures and to pinpoint the beginnings of all life.
Three classification techniques—phonetics, cladistics, and taxonomy groups—can be used to do this. Three major groupings are represented by the tree's branches: Eukaryota (middle branch, letters j to p), Bacteria (left branch, letters a to I and Archea (right branch, letters q to z). Every letter represents a certain category of species. Cladograms and phylograms are the two primary categories of phylogenetic trees. In contrast to phylograms, which do feature scaled branches, cladograms do not reflect the length of time between generations. Rooted or unrooted cladograms and phylograms are also possible.
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peptide bond is a type of covalent bond that could be carried out by which of the following enzymes?
The enzyme that can carry out a peptide bond formation is called peptidyl transferase.
The enzymes that cause the breaking of peptide bonds in proteins are known as proteases or peptididases.
The carboxyl group of one amino acid is joined to the amino group of another to produce a peptide bond, also known as a eupeptide bond. In essence, a peptide link is an amide-type covalent chemical bond. This bond connects two adjacent alpha-amino acids starting at carbon number one (C1) of one and nitrogen number two (N2) of another. This linkage can be discovered along a protein or peptide chain.
The molecules of water (H2O) are released as this bond is being formed. Since the water molecule is removed, a peptide bond is typically a covalent bond (CO-NH bond), and this process is referred to as dehydration. This process typically happens predominantly between amino groups.
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Which statement about bacteria is true?
O Bacteria are always harmful.
O Bacteria are large organisms.
O Bacteria are not successful and are becoming endangered.
O There are more bacteria in the world than all other organisms.
Answer:
the last choice is the answer
{there are more bacteria in the world than all other organisms}
• there are more bacteria in the world than all other organisms.
What is not a responsibility of the nervous system
Answer:
helping us breath is not a responsibility of the nervous system
What is the organization of the genetic material in prokaryotes and eukaryotes?
A nucleoid is the part of the cell that contains this genetic material. Plasmids are tiny DNA loops seen in some prokaryotes that are not required for their regular growth.
What differs in genetic material of prokaryotes?Double-stranded DNA molecules are grouped together in a structure called a nucleoid by prokaryotes.
In addition to this chromosomal DNA, prokaryotes frequently include tiny circular DNA fragments called plasmids that may replicate independently of the chromosomal DNA and contain only a few genes.
In prokaryotes, clusters of genes that can be translated into a single mRNA are known as operons. The majority of the DNA in eukaryotes does not code for a protein.
Therefore, In comparison to eukaryotes, prokaryotes have substantially less non-coding DNA in and between the genes, making their DNA much more compact.
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A nucleoid is the part of the cell that contains this genetic material. Plasmids are tiny DNA loops seen in some prokaryotes that are not required for their regular growth.
What differs in genetic material of prokaryotes?Double-stranded DNA molecules are grouped together in a structure called a nucleoid by prokaryotes.
In addition to this chromosomal DNA, prokaryotes frequently include tiny circular DNA fragments called plasmids that may replicate independently of the chromosomal DNA and contain only a few genes.
In prokaryotes, clusters of genes that can be translated into a single mRNA are known as operons. The majority of the DNA in eukaryotes does not code for a protein.
Therefore, In comparison to eukaryotes, prokaryotes have substantially less non-coding DNA in and between the genes, making their DNA much more compact.
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what would happen if you place your gel in the electrophoresis chamber with the wells containing the DNA next to the red electrode instead of the black?
Placing the DNA wells next to the red electrode instead of the black will result in reverse migration of the DNA in the gel electrophoresis chamber.
In gel electrophoresis, the DNA is separated based on its size and charge by applying an electrical field. The DNA sample is loaded into wells in the gel, and the electrophoresis chamber is connected to a power source.
The black electrode is typically designated as the negative pole, and the red electrode is designated as the positive pole. When an electrical field is applied, the negatively charged DNA molecules will migrate towards the positive electrode (red).
If the wells containing the DNA are placed next to the red electrode instead of the black, the electrical field will be reversed, and the DNA will migrate in the opposite direction, towards the negative electrode (black).
This will result in reverse migration of the DNA in the gel, making it difficult to accurately assess the size and purity of the sample. It is important to follow proper protocol and load the DNA wells next to the black electrode to ensure proper migration of the DNA in the gel electrophoresis chamber.
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Electrophoresis is a method used to separate biological molecules, such as DNA, based on their size and charge. In an electrophoresis chamber, an electric field is applied across a gel matrix containing the sample. The DNA moves through the gel matrix towards the electrode with the opposite charge to its own.
If you were to place your gel in the electrophoresis chamber with the wells containing the DNA next to the red electrode instead of the black, the direction of the electric field would be reversed. The DNA would move in the opposite direction to what was intended and would not separate correctly based on size. This is because the electric field is directed towards the red electrode and the DNA would be moving away from it.
The correct placement of the gel and electrodes is important to ensure that the DNA separates correctly and the results are accurate. The black electrode is typically the anode and is positively charged, while the red electrode is the cathode and is negatively charged. By placing the DNA at the cathode, the negatively charged DNA will move towards the anode and separate based on size as it moves through the gel matrix.
In summary, the correct placement of the gel and electrodes in an electrophoresis chamber is a crucial factor in obtaining accurate results. By placing the gel with the wells containing the DNA next to the red electrode instead of the black, the direction of the electric field would be reversed and the DNA would not separate correctly.
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According to fossil records, the horses that lived 50 million years ago were much smaller, weaker and slower than modern horses. Which process is most likely responsible for the changes that have led to the increased size, strength, and speed in horses?.
Natural selection is most likely responsible for the changes that have led to the increased size, strength, and speed in horses.
What do you mean by natural selection?Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.
Natural selection is the process through which populations of living organisms adapt and change. Individuals in a population are naturally variable, meaning that they are all different in some ways.
Natural selection is a simple mechanism that causes populations of living things to change over time. In fact, it is so simple that it can be broken down into five basic steps- Variation, Inheritance, Selection, Time and Adaptation.
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what is the primary function of protein in the body?
Answer:
Proteins play several critical roles in the body, but the primary function of proteins is to serve as building blocks for tissues and to perform a variety of biological functions.
Some of the key functions of proteins in the body include:
Structural support: Proteins form the structure of many tissues in the body, such as skin, hair, and nails.
Enzymes: Proteins act as enzymes and catalyze chemical reactions in the body, facilitating metabolic processes.
Hormones: Proteins play a crucial role as hormones, regulating growth and metabolism, and transmitting signals between cells and tissues.
Transport: Proteins are involved in the transport of molecules and ions within the body.
Immune system: Proteins serve as antibodies and help to protect the body from harmful pathogens.
Overall, proteins play a vital role in many functions of the body and are essential for maintaining health and well-being.
drugs that block the beta-one adrenergic receptors will drugs that block the beta-one adrenergic receptors will decrease the end-systolic volume. increase cardiac output. decrease heart rate. increase heart rate. increase contractility.
drugs that block the beta-one adrenergic receptors will decrease rate of heart beat.
What are Beta-blockers?Beta-blockers are drugs that help lessen the strain on the heart and blood vessels. Additionally, they can aid in the treatment of several disorders such as tremor, anxiety, and migraine.
Beta-blockers are typically prescribed by doctors to treat heart-related symptoms like angina and excessive blood pressure. they stop the action of hormones like adrenaline that operate on the nervous system. They assist in preventing the stress reaction known as "fight-or-flight" by accomplishing this.
Hormones like adrenaline and noradrenaline get the body's muscles ready for work. This is an essential component of recognizing danger.
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which organelle contains rna and reads the mrna to synthesize a protein
The organelle contains RNA and reads the mRNA to synthesize a protein in the ribosome.
The cell is mаde up of mаny orgаnelles, some of which аre vitаl to the process of synthesizing proteins. These include the nucleus аnd its DNА, ribosomes, endoplаsmic reticulum (ER) аnd the golgi аppаrаtus (GА).
Ribosomes аre vitаl in the process of trаnslаtion, or using the informаtion provided by mRNА to build а protein. These two-pаrt orgаnelles аre mаde up of rRNА or ribosomаl RNА аnd proteins. The ribosome reаds the mRNА аnd tRNА molecules аdd аmino аcid molecules, building chаins of аmino аcid molecules cаlled polypeptide chаins. This orgаnelle cаn be found in the rough ER or free floаting within the cytoplаsm of the cell.
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Rubbing two objects together may cause large number of electrons to be transferred from one object to the other.a. Trueb. False
The statement "Rubbing two objects together may cause a large number of electrons to be transferred from one object to the other" is True.
When we rub two distinct objects together, we increase the contact area between them, which also means that the friction level rises. When two different substances are rubbed against one another, an exchange of electrons takes place from one substance to the other. Because of this, one of the subjects loses electrons and becomes positively charged, while the other subject gains electrons and becomes negatively charged Triboelectric Charging is another name for this process.
Now, if the contact area of two different rubbing objects were to get larger, there would be a greater amount of friction, which would result in a greater number of electrons being transferred from one object to the other.
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Answer the following regarding the process of transcription:
Where does this process take place?
What molecule is used as a template in this process?
What specific molecule is created in this process?
chewing tobacco can lead to a condition characterized by leathery white patches inside the mouth known as
Chewing tobacco can lead to a condition characterized by leathery white patches inside mouth known as leukoplakia.
There are several health hazards associated with smokeless tobacco: On the gum or the inside of the cheek, white, leathery patches (leukoplakia) can develop. These lesions have the potential to develop into oral cancer, a type of cancer that affects the lip, tongue, and cheek.
On your gums, cheeks, and bottom of your mouth, leukoplakia manifests as thicker, impossible-to-scrape-off white areas.
Leukoplakia is a sign of cancer although that is not always the case. How different the aberrant cells' structure, size, and appearance are from normal mouth cells determines the likelihood of getting oral cancer. Dysplasia is the name given to this anomaly.
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Classify each protein example according to its highest level of protein structure.
Primary structure
Secondary structure
Tertiary structure
Quaternary structure
1) the amino acid sequence of myoglobin
2) a single helical chain of collagen
3) a single hemoglobin subunit with heme
4) hemoglobin
Primary structure: amino acid sequence of myoglobin ; Secondary structure: single helical chain of collagen ; Tertiary structure: single hemoglobin subunit with heme and Quaternary structure: hemoglobin (a combination of multiple subunits, each with its own tertiary structure)
What is meant by protein structure?To reiterate, primary structure of protein is defined as the sequence of amino acids linked together to form polypeptide chain and each amino acid is linked to next amino acid through peptide bonds created during protein biosynthesis process.
Protein structure is three-dimensional arrangement of atoms in amino acid-chain molecule. Proteins are polymers formed from sequences of amino acids, the monomers of polymer.
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in the posterior view, the cubital region is __________ to the carpal region.
In the posterior view, the cubital region is proximal to the carpal region.
Posterior in аnаtomy pertаins to the bаck of the body. When describing а body pаrt, it is either locаted posteriorly or аnteriorly. If one is stаnding in the аnаtomicаl position, posterior refers to the bаck side, so the locаtion of the body pаrt is bаsed on this.
The cubitаl fossа is аn аreа of trаnsition between the аnаtomicаl аrm аnd the foreаrm. It is locаted in а depression on the аnterior surfаce of the elbow joint. It is аlso cаlled the аntecubitаl fossа becаuse it lies аnteriorly to the elbow (Lаtin cubitus) when in stаndаrd аnаtomicаl position.
The carpal tunnel is a narrow passageway found on the anterior portion of the wrist. Thus, the cubital region is proximal to the carpal region.
Your question is incomplete, but most probably your options were
A. Distal
B. Proximal
C. Medial
D. Superficial
Thus, the correct option is B.
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Levels of Organization: Label the diagram using the following terms.
Organism
Organ system
Atom
Cells
Molecules
Organ
S
Tissue
Level of Organization of living things:
AtomCellsMoleculesTissueOrganOrgan systemOrgan systemCell is the smallest unit of living things.
Tissue is a collection of cells that have the same shape and function.
Organs are groups of tissues that have the same shape and function.
An organ system is a group of several organs that make up a system.
Organisms are a collection of various organ systems that make up life.
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10. Use the data from the table to create a line graph of the bacteria
population over time.
Time
(in minutes)
0
52
104
156
208
260
312
Number of
Lactococcus
lactis Cells
1
2
4
8
16
32
64
The independent variable in the experiment is the time that have been taken.
What is the independent variable?The independent variable is the variable that is being manipulated or changed in an experiment or study. It is considered the "cause" in the relationship being investigated and its effects are measured through the dependent variable.
We can see that as the time is changing so the number of the bacteria is changing the fore this is the independent variable in the experiment that is taking place here.
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What is the missing word in this sentence? Millimetres of __________ are the units used to measure blood pressure.
Millimetres of Mercury are the units used to measure blood pressure.
what is the role of sigma in bacteria? (choose the one best answer)
The purpose of sigma in bacteria is to connect to the promoter area of a gene.
What other names do hazardous germs go by?The dangerous bacteria are known as "bad bacteria." They are known as pathogens. These might be picked up from our surroundings. Vibrio cholerae, the bacteria that causes cholera, can be caught by ingesting food or water that has been tainted with an affected person's feces, coming into close touch with an infected person, or both.
Which germs are the most powerful?Enterococcus implicit or explicit, which is referred to be "the world's toughest bacteria" in the Guinness Book of World Records, is able to tolerate harsh climates, nutritional shortages, and 1,000 times as much radiation as an adult person.
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Which of the following conditions is required for a target organ to respond to a particular hormone? The target organ must have receptors that recognize and bind the hormone molecule. The target organ must be the same as the organ that produced the hormone. The target organ must have the opposite mating type of the organ that produced the hormone. all of these Cells in the target organ must modify their plasma membranes to allow the hormone to enter the cytoplasm.
The hormone molecule must be recognised and bound by receptors in the target organ.
What is receptors?Receptors are proteins located on the surface of cells that detect changes in the internal or external environment. They are responsible for initiating a signal transduction pathway, which transmits information from the outside environment to the inside of the cell. Receptors can be either ion channels, which allow ions to pass through them, or G-protein coupled receptors, which are linked to a G-protein that activates a cascade of signaling molecules in the cell. Receptors can be specific for certain molecules, such as hormones, neurotransmitters, or environmental molecules. Receptors can also be classified by their location, such as cell surface, intracellular, or nuclear receptors.
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which substance does not promote inflammation kinins pyrogen prostaglandins
substance does not promote inflammation is pyrogen. Pyrogens are substances that have the potential to raise the hypothalamus thermostat's "set point."
As a protective strategy, the body produces inflammation. By identifying and eliminating damaging and alien stimuli, the immune system starts the healing process. Acute or chronic inflammation is a possibility. Acute inflammation can be brought on by bacteria invading the body, trauma-related tissue injury, or toxic substances. As in the case of cellulitis or acute pneumonia, it begins quickly, gets worse quickly, and its symptoms may linger for a few days. The time between acute and chronic inflammation is known as subacute inflammation, and it can last anywhere between two and six weeks. Chronic inflammation is also known as sluggish, long-term inflammation that lasts for a long time—from a few months to years—before subsiding.
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After an embryonic cell inactivates an X chromosome, when the cell divides, its descendants will ___
a) randomly inactivate one of the two X chromosomes after each cell division (Since inactivation has already occurred, the process can no longer be random)
b) maintain inactivation of the same X chromosome
c) always inherit only the X chromosome that remains active
d) always inherit only the X chromosome that was inactivated
After an embryonic cell inactivates an X chromosome, when the cell divides, its descendants will maintain inactivation of the same X chromosome so the correct option is B.
X-chromosome inactivation helps to insure that each cell has the same number of active X chromosomes as other cells in the organism. This helps to maintain the correct balance of gene expression between the two relations, as well as icing that gene is duly regulated.
which can lead to inheritable conditions similar as X-linked internal deceleration. In summary, when an embryonic cell inactivates an X chromosome, its descendants will maintain the same X chromosome inactivation.
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____ neutralizes the acidic chyme as it enters the small intestine.
Answer: Bicarbonate neutralizes the acidic chyme as it enters the small intestine.
Explanation: I looked it up + trust me bro
2.1.6 Explain the importance of the surface area to volume ratio as a factor limiting cell size.
Smaller single-celled creatures have a higher surface area per unit volume, which enables them to rely on waste removal and oxygen diffusion to thrive.
What sort of creature is that?A solitary or unique live species that exhibits all the traits of life is often referred to as an organism. These might be an animal, plant, bird, microbe, or even an insect.
Who are the seven living things?Movement, breathing or ventilation, excretion, development, sensitivity, and reproduction are the other six traits of living creatures. While some non-living creatures could exhibit one or several of these traits, only live organisms exhibit all seven traits.
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Michael learns that some genetic variations increase the probability of certain individuals in a population surviving and then reproducing in their environment. Describe and give an example of how a genetic variation might increase survival in a population.
It enables the members of a population to endure and produce offspring with the necessary trait for survival, while those without it will disappear.
What is genetic variation?A population of people with a diversified genetic makeup has a higher chance of surviving than one with a homogeneous genetic makeup.
A population's variation enables certain members to adapt to the shifting environment, and natural selection enables the expression of those advantageous traits to endure.
Therefore, natural genetic variations among members of the same species are referred to as genetic variation.
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What is the relationship between rough endoplasmic reticulum ER and lysosomes?
The lysosome enzymes are produced by the rough endoplasmic reticulum. The production of lysosomal enzymes takes place in the rough endoplasmic reticulum.
What are lysosomes and what do they do?The digestive system of something like the cell, lysosomes break down materials received from the outside world as well as any unnecessary cell components. They could be used to get rid of unwanted viruses and bacteria.
Where are lysosomes located?Lysosomes are present in every animal cell, however they are mostly found in white circulation cells and many other immune-system supporting cells. White blood cells must ingest more nitrogen than the preponderance of other types of organisms in order to fight off pathogens, parasites, and other external foes.
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Which of the following is not true regarding metabotropic receptors?
a. The receptor itself is an ion channel that opens upon ligand binding
b. The receptor has one subunit with seven transmembrane domains
c. They are coupled to intracellular G proteins
d. When activated they can stimulate effector enzymes
The statement that is not true regarding metabotropic receptors is Ion channels built into the receptor themselves open in response to ligand binding. The correct answer is option(a).
A metabotropic receptor likewise refers to by one more extensive term G-protein-connected receptor, is a type of membrane receptor that introduces any metabolic steps to harmonize container endeavor. The central nervous system appropriates two types of receptors: metabotropic and ionotropic receptors.
A ligand is an ion or particle, that donates a pair of electrons to the central mineral modicum or ion to form an arrangement complex. The word ligand is from Latin, which wealth is “tie or bind”. Ligands may be anions, cations, and noncommittal particles. Ligands play multiple parts grazing from the managing of the solubility and chance of alive elements all the while NP combining to the post-artificial minimization of surface strength of NPs (necessary for their colloidal security) in addition to the encrypting of NP use.
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