When B cells interact with any antigens it gets divided into B plasma cells and B memory cells. Plasma B cells produce antibodies against antigens or pathogens found in the blood.
What is the difference between effector B cells (plasma cells) and cytotoxic T cells?
When B cells interact with any antigens it gets divided into B plasma cells and B memory cells. Plasma B cells produce antibodies against antigens or pathogens found in the blood. These antibodies bind to the antigen's epitope and aid in its destruction by phagocytic cells.
Pathogen elimination by cytotoxic T cells is a completely different process. Cytotoxic T cells bind to pathogen-infected cells and release cytotoxic enzymes that kill the pathogen-infected cell.
As a result, B-cells secrete antibodies against pathogens, and cytotoxic T cells kill pathogen-infected cells.
Therefore, the correct answer is option E.)B cells secrete antibodies against a virus; cytotoxic T cells kill virus-infected cells.
The complete question is:
Which statement best describes the difference in responses of effector B cells (plasma cells) and cytotoxic T cells?
A.)B cells respond the first time the invader is present; cytotoxic T cells respond subsequent times.
B.)B cells confer active immunity; cytotoxic T cells confer passive immunity.
C.)B cells accomplish the cell-mediated response; cytotoxic T cells accomplish the humoral response.
D.)B cells kill viruses directly; cytotoxic T cells kill virus-infected cells.
E.)B cells secrete antibodies against a virus; cytotoxic T cells kill virus-infected cells.
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A student who was trying to determine the concentration of escherichia coli in a sample completed a total plate count assay. After plating 1ml of the 10-6dilution tube and incubating the plate at 37C for 24 hours the student counted 210 colonies on the plate. What is the cfu/ml of the original sample?.
The cfu/ml of the original sample of escherichia coli is 2.1*10^8.
Concentration in chemistry can be calculated by dividing a constituent's abundance by the mixture's total volume. The concentration of the escherichia coli in a sample determined by a student would be 2.1*10^8. Mass concentration, molar concentration, number concentration, and volume concentration are four different categories of mathematical description.
Any type of chemical combination can be referred to by the term "concentration," however solutes and solvents in solutions are most usually mentioned. There are many types of molar (quantity) concentration, including normal concentration and osmotic concentration, the practice or act of focusing: the quality of being focused, especially: giving all of one's attention to one thing. A concentration inside a major or a major's academic major. The student decided to concentrate on law.
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You discover a new egg-laying worm species. You dissect four adults and find both oocytes and sperm in each. Cells outside the gonad contain five chromosome pairs. Lacking genetic variants, how would you determine whether the worms can self-fertilize?
The worms' ability to self-fertilize can be tested by an experiment. Worms can reproduce asexually since they have both oocytes and sperm, therefore they don't need the assistance of another worm.
Self-fertilization occurs in amphoteric organisms, including most flowering plants, numerous protozoa, and many invertebrates. Autogamy, the production of gametes by the division of a single parent cell, is commonly found in unicellular organisms such as the protozoan Paramecium. However, these organisms can also reproduce by conjugation. In conjugation, cross-fertilization is achieved by the exchange of genetic material between two individuals through cytoplasmic bridges. Similarly, while most higher plants are hermaphroditic (i.e., hermaphroditic, male and female gametes are produced by the same individual), most self-pollinated species are also capable of cross-pollination, Even those that mandate pollination, pollinators occasionally cross-pollinate at random.
Hermaphrodites (animals in which both male and female gonads are carried by the individual) are rarely capable of self-fertilization, as many of these species have adaptations that facilitate cross-fertilization.
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laboratory and field evaluation of host-related foraging odor-cue combinations to attract drosophila suzukii (diptera: drosophilidae). j
The invasive noticed-wing drosophila, Drosophila suzukii (Matsumura), is a chief pest of smooth-skinned culmination. on account that its creation into North the USA and Europe, widespread development has been made in understanding the risky cues utilized by this fly at some point of food, oviposition site, and mate finding.
Drosophila suzukii enchantment and selectivity. In laboratory assays, men and women have been attracted to all seven character compounds, despite the fact that in electrophysiological assays, their antennae exhibited a dose-dependent reaction to most effective four of these compounds.
In -preference cage studies, the Fermentation lure turned into extra appealing to Drosophila suzukii than water controls, whereas β-cyclocitral and the aggregate of isoamyl acetate and isobutyl acetate have been now not attractive in this large-cage have a look at. moreover, adding the two-component H. uvarum compound blend to the Fermentation lure decreased Drosophila suzukii enchantment to the Fermentation mixture.
This study demonstrates that cues from distinctive resources may also interfere with every other and reduce Drosophila suzukii enchantment to in any other case attractive odor combinations.
Disclaimer:- your question is incomplete, please see below for complete question.
Laboratory and field evaluation of host-related foraging odor-cue combinations to attract drosophila suzukii (diptera: drosophilidae). j
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Which of the following best describes three of the known causes of foodborne illness?
a) Inadequate cooking, dirty sanitizer on the cook line, and advanced food preparation
b) Poor handwashing, food contamination, and lack of temperature control
c) Using dirty wipe cloths, poor oral hygiene, and improper disposal of fryer oil
d) Storing personal belongings with food items, unshielded light bulbs, and poor management
Answer:
b) Poor handwashing, food contamination, and lack of temperature control
Explanation:
______ is like a language interpreter that converts the genetic message carried by ______ into the language of protein.
Answer:
ribosome
mRNA
Explanation:
The ribosome is like a language interpreter that converts the genetic message carried by mRNA into the language of protein.
Ribosomes are an essential organelle. It is crucial for the creation of protein, a chemical required for metabolism and growth. Protein is produced by the ribosomes for use inside and outside the cell.
What is the importance of ribosomes inside the cell?
A sophisticated macromolecular element of the organism that helps with translation is called a ribosome. To make proteins and a wide range of other biological components, all living cells need to perform this crucial process.
Ribosomes in eukaryotes contain roughly equal amounts of protein and rRNA. Typically, ribosomes include three or four rRNA molecules and between 40 and 80 distinct ribosomal proteins.
Two subunits, a larger and a smaller one, make up each ribosome, and each of them has a distinct form.
Therefore, ribosome functions as a kind of linguist, translating the genetic information carried by mRNA into the language of protein.
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When a sample accurately reflects the characteristics of the population, it is said to be _____.
When a sample accurately reflects the characteristics of the population, it is said to be representative sample.
What is a Population?
This is defined as the total number of people or elements in a particular area over a given period of time.
Representative sample on the other hand is commonly used in statistical analysis and forms a subset of a population. This type of sample must be however be free from any type of bias and also reflects the feature and characteristics of the population which is why it is referred to as a representation of the sample or data given.
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producing energy that fuels the activities of the cell is a function of the . a. myelin sheath b. axon terminals
producing energy that fuels the activities of the cell is a function of- c. cell body
Neurons are the structural and functional part of the nervous system. It is divided into dendrites, cell body and axon.
The dendrites are responsible for carrying the action potential into the cell. The cell body have the organelles like nucleus, mitochondria and nissl granules.
The axon carries the action potential into the next nerve cell. sometimes it can be covered with myelin sheath which increases the speed of transmission of nerve impulse.
Since mitochondria are responsible for producing the energy which are present in the cell body. Cell body will be producing energy required for cell.
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Which statement accurately describes the charge of the nucleus of an atom? (1 point)
a
The nucleus can be either positively charged or neutral.
b
The nucleus never has an electrical charge.
c
The nucleus always has a positive charge.
d
The charge of a nucleus can change from positive to negative.
Option (a) is the correct answer as the nucleus of an atom can either be positively charged or neutral.
Atoms are fundamental constituents of all matter. The three subatomic components of an atom are protons, neutrons, and electrons.
Only protons and neutrons make up the nucleus of an atom, while the nucleus is surrounded by electrons. The charge of protons, electrons and neutrons is positive, negative and neutral respectively.
Equivalent numbers of protons and electrons make up a neutral atom. As a result, the atom turns neutral since positive and negative charges cancel each other out.
A nucleus of an atom can therefore either be neutral or be positively charged.
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Which of these is the lowest level of organization?
A. Organ
B. Tissue
C. Cell
D. Organ System
Answer: Cell
Explanation:
All the others are made up of cells
Answer: The levels, from smallest to largest, are: molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere.
Organic matter in soils make them less suited for agriculture. group of answer choices
a. true
b. false
What are two examples of chemical weathering?(1 point)
abrasion and carbonation
abrasion and carbonation
hydrolysis and oxidation
hydrolysis and oxidation
oxidation and frost wedging
oxidation and frost wedging
exfoliation and hydrolysis
Answer:
oxidation and frost weathering
ii) Explain why yam cannot follow cassava in a crop rotational plan.
In certain regions, cassava is sown shortly after or concurrently with yams. Cuttings from cassava are inserted into the yam mounds' sides. In other locations, beans, groundnuts, or maize are cultivated in between the cassava plants. It is best to avoid growing numerous crops at once.
Crop rotation – what is it?Crop rotation is the technique of successively growing different crops on the same plot of land in an effort to improve soil health, increase nutritional content, and minimize insect and weed pressure.
Why is crop rotation necessary and what does it entail?Crop rotation entails planting a series of various crops in one site across several seasons. Crop rotation contributes to long-term farm production maintenance or improvement of soil health.
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vinblastine, a chemotherapeutic drug used to treat breast and testicular cancers, interferes with the assembly of microtubules. speculate how this drug works to inhibit cancer cell growth.
Vinblastine disrupts mitotic spindle formation and consequently mitosis. Vinblastine is used to treat non-lymphoma Hodgkin's (types of cancer that start in a type of white blood cell that normally fights infection), Hodgkin's lymphoma (Hodgkin's disease), and testicular cancer in combination with other chemotherapy drugs.
It's possible to experience injection site pain or redness, nausea, vomiting, constipation, fatigue, and appetite loss mitosis. Severe nausea and vomiting are possible. Your doctor may occasionally recommend medicine to treat or prevent nausea and vomiting. A little perennial plant that is indigenous to the island of Vinblastine is called Catharanthus roseus, popularly known as Madagascar periwinkle.
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linde, j., et al., data-and knowledge-based modeling of gene regulatory networks: an update. excli journal, 2015. 14: p. 346
The sentence is a part of a study about the Interactions between genes with the help of high-throughput data which were predicated by the gene regulatory network inference which is the biology system approach.
The updated network inference methods were presented on unexplored techniques for network inference assessment, data acquisition network inference for the integration of prior knowledge and interacting species. After the next generation, sequencing of cDNAs was derived from the RNA samples, there were applications in the network interference, there was a progression for both large-scale and small-scale genomic and condensed network inference, and advances were examined in the network inference methods because of crowdsourcing. There was current availability of prior knowledge sources and there was a perspective that recalls interacting species for the interference of the gene regulatory networks.
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What are the roles of gathering and interpreting data in the process of scientific inquiry?
The roles of gathering and interpreting data in the process of scientific inquiry are:
Scientific knowledge is based on data derived from direct or indirect observations of the natural physical world. We collect data using our senses: sight, hearing, touch, taste, smell - to observe. Careful observation often involves measuring something. Observations are influenced by what you already know.Data interpretation involves creating meaning from observations. The conclusion you draw from an observation is called an inference.
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Based on the law of conservation of energy, which statement is correct?
A.Energy is always being added to all parts of the universe.
B. Energy is often destroyed in some parts of the Universe.
C.Energy is a closed system cannot change forms.
D.Energy in an isolated system remains constant.
Answer:
D. Energy is an isolated system that remains constant.
Explanation:
The law of conservation of energy states that the amount of energy is neither created nor destroyed, (but can be only changed from one form into another or transferred from one object to another).For example, when you play the piano and hit the keys, the energy of the person who plays the piano, will be transferred to the keys of the piano.
• According to the law of conservation whenever a form of energy transforms and changes to another, the total amount of energy remains constant,
the answer towards your question shall be D. is the correct statement.
following an action potential, activity of the reestablishes the sodium and potassium ion distribution across the cell membrane.
Following an action potential, activity of the sodium-potassium pump reestablishes the sodium and potassium ion distribution across the cell membrane.
An action potential is a sudden, brief change in the electrical potential of a cell. This shift in potential causes an ionic current that rapidly runs through the cell membrane. The sodium-potassium pump is an important part of this process, as it helps to restore the sodium and potassium ion distribution across the cell membrane.
After an action potential has passed, the sodium-potassium pump works to maintain the electrochemical gradient of the cell. This gradient is essential for keeping the cell in a state of homeostasis, or balance. The pump does this by moving sodium and potassium ions in and out of the cell.
The sodium-potassium pump is a vital part of cell function and is necessary for maintaining homeostasis within the cell.
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Among the themes targeted by the national academy of engineering's grand challenges for engineering as 'essential for humans to flourish' is?
Environmental sustainability is among the themes targeted by the national academy of engineering's grand challenges for engineering as 'essential for humans to flourish'.
What is Environmental sustainability?Environmental sustainability makes reference to the sustainable use of natural resources in order to protect the Earth's planet, which is a fundamental ecological issue.
In conclusion, environmental sustainability is among the themes targeted by the national academy of engineering's grand challenges for engineering as 'essential for humans to flourish'.
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Many scientists think that fetal tissue transplants offer great potential for treating Parkinson's disease, epilepsy, diabetes, Alzheimer's disease, and spinal cord injuries. Why might tissues from a fetus be particularly useful for replacing diseased or damaged cells in patients with such conditions? Some people would allow only tissues from miscarriages to be used in fetal transplant research. However, most researchers prefer to use tissues from surgically aborted fetuses. Why? Explain your position on this controversial issue.
Tissues from a toddler are better for the treatment of the mentioned disorders as they are the best for stem cell therapy.
What is stem cell therapy?The body's building blocks are stem cells, which are cells that give rise to all other cells with specific roles. Daughter cells are created when stem cells divide properly in the body or a lab to create additional cells.
These daughter cells may develop into fresh stem cells or into differentiated cells with a more particular role, such as bone, blood, brain, or heart muscle cells. No other cell in the body has the capacity to naturally produce different cell types.
Therefore, tissues from a toddler are better for the treatment of the mentioned disorders as they are the best for stem cell therapy.
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What determines whether a cell responds to a hormone such as epinephrine? What determines how a cell responds to such a hormone?
A cell can only respond to a hormone if it contains a receptor protein that can bind to the hormone on its surface or within the cell. The cellular response to a hormone is determined by the unique signal transduction route within the cell that leads to the specific cellular response. The reaction varies depending on the type of cell.
Epinephrine binds to a receptor on the surface of cells such as the liver, skin, heart, and lungs. Epinephrine stimulates the breakdown of glucagon into glucose in the liver, providing the body with instant energy. In the skin, epinephrine decreases blood flow, enabling more blood to be pumped to the muscles, but in the lungs, it relaxes smooth muscle cells, allowing for more air movement. Finally, it causes the heart's contraction rate to rise. All of the components are intended to assist the body to expend as much energy as possible to aid in the fight or flight response.
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A population of raccoons lives in a forested area with lots of trees. The raccoons eat insects, eggs, berries, nuts, and small animals such as
rodents and frogs. One of the main predators of the raccoons are coyotes, which also prey on rabbits.
Identify whether the changes to the ecosystem are more likely to increase or decrease the population of raccoons.
More permits to hunt
Pollution from a nearby farm
disease decreases
coyotes are approved.
decreases the population
the population of rabbits
of insects in the forest.
in the forest.
Large parts of the forest
Additional rain increases
Frogs in a pond near
are cut down for wood.
the population of plants
the forest experience |
in the forest.
population surge.
Increases Population
Decreases Population
Answer:
since theres 6 examples , im assuming 3 go in " increases " and 3 go in " decreases " so , here you go :
Explanation:
INCREASES : addition rain makes more plants grow ( if there are more plants , raccoons can get more food and plus the rabbits will also eat the plants so the coyotes might go for either which doesnt freak out the raccoons as much )
INCREASES : frogs grow in population ( similar to the rain / plant example , the raccoons will have more food available to them , which means that the babies wont die and raccoons wont die of hunger )
INCREASES : more coyote kill permits ( i mean , people who hunt want some type of challenge and saying you shot a coyote is way cooler than saying you shot a raccoon , and also less coyotes , less raccoons they need to eat )
DECREASES : pollution from the farm kills insects ( the raccoons will have less food since they eat insects which means more raccoons will die of hunger )
DECREASES : the disease kills off rabbits ( if there arent rabbits , then the coyotes will only have raccoons to eat so theyll end up killing off the raccoons )
DECREASES : wood is cut down ( thats going to remove the food that the raccoons eat such as eggs and rodents and nuts , so theyre probs going to starve to death )
please tell me this helps lol
Clots in arteries can cause heart altacks and strokes. Why, then, does it make sense to treat people with hemophilia by introducing clotting factors into their blood?
Hemophilia is a bleeding disorder marked by a genetic incapacity to efficiently clot blood.
Although they are necessary proteins for the coagulation process, clotting factors do not really cause clotting. In order to treat hemophilia and avoid blood loss in the event of an accident or injury, clotting factors must be injected into the patient's blood.It can result in spontaneous bleeding as well as bleeding after an operation or an accident. A blood protein known as a clotting factor helps to stop bleeding.Clotting factors are plasma components required for blood to clot. Therefore, the best method for treating hemophilia is blood clotting factor replacement, which enables normal blood clotting. A clotting factor concentrate is routinely injected into a hemophilic person's vein as part of the treatment process.Learn more about the hemophilia with the help of the given link:
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The graph shows the world human population size and growth rate over time. How are the two sets of data related to each other? What does studying one data set tell you about the other?
With the x-axis being linear and the y-axis being logarithmic, the graph is thus semi-logarithmic.
The relative rate of population growth is displayed. On this graph, a population that expands at a steady rate is depicted as a straight line, although the actual population size grows exponentially.
Over the course of the last 200 years, the population has grown from roughly 1 billion to over 7 billion people at an accelerating rate.We find the difference (subtract) between the original population and the population at Time 1, divide by the initial population, then multiply by 100 to obtain the Population Growth (PG). For that time (10 years), the population growth rate (PGR) was 12%.Through technology, urbanization, and the use of fossil fuels as energy, humans have improved their carrying capacity. We can forecast population increase using a population's age distribution.Learn more about human population here:
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Which organelle adis in the production and movement of proteins and other materials through the cell ?
Answer: The organelle that aids in the production and movement of proteins and other substances through the body is known as the endoplasmic reticulum. This cell organelle is essential for synthesis of membrane lipids and proteins.
Explanation:
Studies examining the education level of inmates in correctional facilities found that many inmates had attained a(n) ________ _________ level of education or less.
Studies have shown that inmates have an eighth-grade education level or less.
What conclusions can be drawn from this?Crime is more associated with low adherence to education.The incarceration rate is inversely proportional to the education rate.When researching the educational level of American inmates, it was concluded that most inmates had an eighth-grade education level or less, which shows that lack of access to education is a common factor in individuals who engage in criminal activities.
This reinforces the need to create a quality education system and provide sufficient resources for all people to have access to these systems.
Thus, greater adherence to education will reduce the level of individuals involved in crime.
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In testing the optimal foraging model, it was assumed that changing the height of the drop only changed the total energy required. Do you think this is a realistic limitation, or might other factors than total energy be affected by height?
The behavioural ecology refers to this animal activity as foraging. Energy, or calories, vitamins, minerals, and protein are the main nutrients that animals obtain through fending for themselves. Foraging is divided into two different types: solitary foraging and group foraging.
Crows are an example of foragers since they prey on eggs, adult birds, and whelk.
What is the prediction of optimum foraging?A behavioural ecology model called optimal foraging theory (OFT) may be used to forecast how an animal will act when looking for food. Even while eating gives an animal energy, finding and collecting the food requires both time and energy.
Although foraging for food is necessary to sustain physiological function, the energy required to do so has a cost.
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filipowicz, w., bhattacharyya, s. n., and sonenberg, n. (2008). mechanisms of post-transcriptional regulation by micrornas: are the answers in sight? nat. rev. genet. 9, 102–114. doi: 10.1038/nrg2290
Mechanisms of post-transcriptional regulation by microRNAs: are the answers in sight, the statement is correct.
What is microRNA?microRNAs are the Short non-coding RNAs which is otherwise called as miRNAs that results in post-transcriptional gene expression.
MicroRNA discovered in Caenorhabditis elegans in 1993, on the other hand Gary Ravkun identified the miRNA target gene involve in posttranscriptional gene regulation.
These are small RNA molecules encoded in both plants and animals, highly conserved 22 nucleotides long RNA sequences and they regulate the expression of genes by binding to the 3'-untranslated regions.
A growing body of evidence shows that miRNAs are one of the key players in cell differentiation and growth, mobility and apoptosis.
miRNAs from other classes of small RNAs in the cell particularly the distinction from endogenous small interfering RNAs, regulate the development and physiology, understanding its biological role.
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The layer of polysaccharides, which functions to help bacteria adhere to surfaces, prevents drying, and helps to resist a host's immune system is called the _____.
According to the research, the correct option is Glycocalyx. The layer of polysaccharides, which functions to help bacteria adhere to surfaces, prevents drying, and helps to resist a host's immune system is called the Glycocalyx.
What is Glycocalyx?It is the layer of carbohydrates or filamentous material that covers some bacteria and is mainly composed of polysaccharide, phospholipids or plasma membrane proteins.
In this sense, it contributes to protecting the cell surface from mechanical and chemical aggressions, as well as playing an important role in the processes of recognition and adhesion between cells.
Therefore, we can conclude that according to the research, the correct option is Glycocalyx. The layer of polysaccharides, which functions to help bacteria adhere to surfaces, prevents drying, and helps to resist a host's immune system is called the Glycocalyx.
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Rna contains equal proportions of g and c nucleotides. true false
Erwin Chargaff disproved an earlier hypothesis that the four bases were present in equal proportions, and dispelled the view that DNA was too simple and uniform to hold genetic information.
Does RNA contain C and G?An RNA molecule has a backbone made of alternating phosphate groups and the sugar ribose, rather than the deoxyribose found in DNA. Attached to each sugar is one of four bases:
adenine (A)uracil (U)cytosine (C) or guanine (G).With this information, we can conclude that Erwin Chargaff analyzed the base composition of DNA from diverse sources and discovered consistent ratios of the bases among all the sources.
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phylogenies represent how different species or groups of organisms may be related through evolutionary time.
DNA-DNA hybridisation is used to check the similarity in organisms.
What is evolution?
Evolution is defined as change in the characteristics that acquired heritableyand of population exposed to generations which are successive. There are several stages of evolution through which an organism pass to achieve the evolution and these are mutation, after that genetic recombination, reproduction isolation, and natural selection.
The neck of the giraffe is the best example of evolution as the time change the length of the neck of the giraffe becomes long because due to height of tree they strech their neck and due to practice over a long time the evolution takes place and their neck become long in length. Evolution is a time taking or long process.
Therefore, DNA-DNA hybridisation is used to check the similarity in organisms.
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