The early Greeks' atomic theory of matter. Democritus thought that atoms were uniform, hard, solid, incompressible, and unbreakable, and that they travelled endlessly across empty space until coming to a stop.
The various properties of matter were determined by variations in atomic size and shape. The concept that everything is made up of atoms was first proposed by the ancient Greeks. Democritus is credited with accomplishing this entirely with the power of his intellect because there were no microscopes or other scientific tools at his disposal.
The Greeks thought that atoms were the tiniest units of substance and could not be further subdivided. The English chemist John Dalton didn't begin to formulate a more precise concept of the atom until 1803. In describing atoms, he took inspiration from Ancient Greek concepts.
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Correct Question:
Justify with your words the importance of thinking and checking experimentally, just as the ancient thinkers did to create the concept of atom. ( Spanish: Justifica con tus palabras la importancia de pensar y comprobar experimentalmente , tal cual lo hicieron los pensadores antiguos para crear el concepto de átomo)
A sample contains 1. 67 times more 207pb than 235u. How old is the sample?
The age of the sample is approximately 4.51 billion years.
The age of a sample can be determined using the ratio of two isotopes of uranium, 235U and 207Pb, in the sample. The age can be calculated using the formula:
Age = (1 / λ) x ln (Nf / N0 + 1)
where λ is the decay constant, Nf is the current number of daughter atoms (207Pb), and N0 is the initial number of parent atoms (235U).
Given that the sample contains 1.67 times more 207Pb than 235U, we can assume that the initial ratio of 235U to 207Pb was 1:1.67. Therefore, N0 = Nf / 1.67.
The current ratio of 235U to 207Pb in the sample can be measured using various analytical techniques. Let's assume that the current ratio is 0.02.
The decay constant of 235U is 9.85 x 10^-10 per year.
Plugging these values into the formula, we get:
Age = (1 / 9.85 x 10^-10) x ln (0.02 / (1 / 1.67) + 1)
= 4.51 billion years
This is consistent with the age of the Earth, which is estimated to be around 4.54 billion years.
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Need help with this for a science project
Answer: Proteins
Explanation:
Grasshoppers and crickets have an Xo system of sex determination. Every female has two X chromosomes, whereas every male has only one X chromosome and no second sex chromosome. There are no Y chromosomes.
What sex chromosome will every ovum contain? Which parent determines the sex of the offspring in grasshoppers and crickets? Explain ...
Each of the female's eggs has one X chromosome because she is a XX. Due to his XY genetic makeup, males can produce sperm that has both X and Y chromosomes in equal amounts.
Does the sperm in grasshoppers decide the sex of both the offspring?The type of sperm cell, which may not include the X chromosome, determines the sex of the baby. Because they have two pairs of X chromosomes and are referred to as XX, female grasshoppers are gay marriage by nature. As a result, the type of genome found in the sperms determines the sexes of the kid.
What determines a grasshopper's gender?The XX/XO sex classification system is used by grasshoppers, which is the short answer to your query. Let's now talk about what the X and O represent and the way they are used to tell male versus female grasshoppers apart. As they only have one X chromosome, male grasshoppers are classified as XO.
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Compose a 450 word report on the responsibilities of hazardous waste technicians and how they keep themselves safe during their job duties.
You may use additional resources if necessary, but be sure to include the proper citations.
Part 2
Explain the four main characteristics of hazardous waste.
Part 3
Explain four treatment options for hazardous waste.
Part 4
Describe the difference between chronic and acute exposure
Answer:
Part 1: Responsibilities and Safety of Hazardous Waste Technicians
Hazardous waste technicians are responsible for safely managing and disposing of hazardous materials. This includes identifying, collecting, packaging, transporting, and disposing of hazardous waste in compliance with federal, state, and local regulations. The job also involves monitoring and analyzing waste materials to ensure they are handled and disposed of properly.
To protect themselves from potential exposure to hazardous materials, technicians follow strict safety procedures. This includes wearing personal protective equipment, such as gloves, respirators, and coveralls, as well as using proper containment and handling techniques. They also receive specialized training on handling hazardous materials and emergency response procedures.
In addition, hazardous waste technicians must stay up to date with changing regulations and technology. This includes attending regular training and continuing education programs, as well as monitoring industry developments and advancements in waste management technology.
Part 2: Characteristics of Hazardous Waste
Hazardous waste can be defined as any material that is potentially harmful to human health or the environment. There are four main characteristics of hazardous waste: ignitability, corrosivity, reactivity, and toxicity.
Ignitability refers to materials that can easily catch fire, such as solvents and petroleum products. Corrosivity refers to materials that can erode or dissolve materials, such as acids and bases. Reactivity refers to materials that are unstable and can potentially explode or release toxic gases when mixed with other substances. Toxicity refers to materials that can cause harm to human health or the environment, such as heavy metals and pesticides.
Part 3: Treatment Options for Hazardous Waste
There are several treatment options for hazardous waste, including physical, chemical, and biological methods. Physical methods involve separating hazardous waste from non-hazardous waste, such as through filtration or evaporation. Chemical methods involve neutralizing hazardous waste through chemical reactions, such as by adding acid or base to adjust the pH. Biological methods involve using microorganisms to break down hazardous waste, such as through composting or bioremediation.
Another treatment option is incineration, which involves burning hazardous waste at high temperatures to convert it into less harmful byproducts. Landfill disposal is another option, although it is considered the least desirable due to the potential for environmental contamination.
Part 4: Chronic and Acute Exposure
Chronic exposure refers to long-term exposure to hazardous materials, such as through daily exposure in the workplace or living near a contaminated site. This type of exposure can lead to health problems over time, such as cancer, reproductive issues, and neurological disorders.
Acute exposure, on the other hand, refers to short-term exposure to high levels of hazardous materials, such as through a chemical spill or accidental release. This type of exposure can cause immediate health effects, such as respiratory distress, burns, and chemical burns.
It is important for hazardous waste technicians to be aware of the risks associated with both chronic and acute exposure, and to take appropriate measures to protect themselves and others from potential harm.
The difference between chronic and acute exposure:
Chronic exposure refers to the long-term or repeated exposure to a hazardous substance over a period of time, such as months or years. This exposure may occur at low levels, but can still lead to adverse health effects. Chronic exposure can result in diseases that develop slowly, such as cancer, reproductive disorders, and neurological damage.
Acute exposure, on the other hand, refers to short-term exposure to a hazardous substance that results in immediate and severe health effects. This exposure can occur in a single incident or over a brief period, such as hours or days. Acute exposure can lead to symptoms such as skin irritation, respiratory distress, vomiting, and even death.
In summary, chronic exposure occurs over a long period of time and can result in diseases that develop slowly, while acute exposure occurs over a short period of time and can lead to immediate and severe health effects.
The amount of money that a company is forced to pay as a fine or penalty typically depends on how much damage its actions and products have caused. Suppose the Environmental Protection Agency (EPA) catches a company dumping a toxic chemical into a river. Who is BEST able to assess the resulting damage to the environment without having to worry about bias? A. a scientist employed by the company who works with the chemical B. a scientist employed by the EPA who knows the river ecosystem C. an independent scientist without ties to the company or the EPA D. any scientist who is knowledgeable about this type of pollution
compare and contrast two types of plant described in this passage and how are they similar and how are they different refer to the text in your answer and explain your arguments completely
Carnivorous plants are classified into four types: Pitcher plants, bladderworts, and Venetian Flytrap
What is the distinction between a Venetian Flytrap and a solar plant?The Venus flytrap is an active companion of carnivorous plants. It is also known as Dionaea muscipla. The insects are drawn to the narrow part of this plant, which is 100 miles long and 10 miles wide, where the solar plant, an extraordinarily intelligent carnivorous plant, the sundew plant, will sprout 100 tentacles. It was following the genus Drodera.
What is the distinction between Thrower Plants and Bladderworts?It has two sorts of plants. Numerous colourful images were spread throughout the plant, and the Bladderworts were exceedingly little and resembled the sacs in which they were found. Utricularia is another name for this plant.
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the function of stomata
Answer:
The functions of Stomata are given below :
1. It helps in transpiration of water.
2. It helps in exchange of gases.
3. It helps to create an upward pull which helps in the process of absorption of water from the root.
4. It takes carbon dioxide and gives out Oxygen at the time of Photosynthesis.
5. It helps to regulate water movement through transpiration.
Atoms are the most basic unit of matter. Two or more atoms from the same or different elements can combine to form molecules.
Cells are the most basic unit of life. Cells are made up of many different types of molecules. Which of the following accurately shows higher levels of organization within organisms, from least complex to most complex?
A.
cells → tissues → organs → organ systems → organism
B.
cells → organs → tissues → organ systems → organism
C.
cells → organ systems → organs → tissues → organism
D.
cells → organs → organ systems → tissues → organism
Answer:
THE ANSWER IS
A : cells → tissues → organs → organ systems → organism
Explanation:
Answer:
A : cells → tissues → organs → organ systems → organism is the answer
Explanation:
a genetic screen for eye color mutants resulted in five fly strains with independent mutations: three with white eyes and two with orange eyes. the genomic locations of each of the five mutations has been identified. what results are possible? check all that apply.
The possible results from the genetic screen for eye color mutants are that all five mutations are located on different chromosomes, or that two of the mutations are on the same chromosome and the other three are on different chromosomes.
The eye color mutations in the five fly strains may be located on different chromosomes or on the same chromosome. If all five mutations are located on different chromosomes, they will independently assort during meiosis and produce offspring with all possible combinations of eye colors.
If two of the mutations are located on the same chromosome and the other three mutations are on different chromosomes, then the mutations on the same chromosome will tend to be inherited together and produce offspring with two of the five possible eye colors.
Therefore, the correct answer is that all five mutations are located on different chromosomes, or that two of the mutations are on the same chromosome and the other three are on different chromosomes.
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many bacteria that were originally classified in the genus streptococcus are now placed into two new genera, enterococcus and lactococcus. group startstrue or falsetrue, unselectedfalse
Many bacteria that were originally classified in the genus Streptococcus are now placed into two new genera, Enterococcus and Lactococcus. This statement is true.
Bacteria are microscopic, single-celled organisms that lack nuclei and organelles. They belong to the kingdom Monera, which is the simplest of the five kingdoms of life. Bacteria are divided into two groups based on their cell wall structure: Gram-negative and Gram-positive.
Bacteria are classified into different genera based on their characteristics such as structure, chemical composition, physiological characteristics, and others. Streptococcus is a genus of spherical, gram-positive bacteria that belong to the phylum Firmicutes. Many bacteria were originally classified in the genus Streptococcus but are now placed into two new genera, Enterococcus and Lactococcus.
Enterococcus and Lactococcus are two genera that were separated from the genus Streptococcus. These organisms were separated from the genus Streptococcus because of differences in their DNA sequences and phenotypic characteristics.
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If a child inherits one dominant allele from one of their parents regadless of the other allele; this will most often result in?
Either recessive or dominant trait.
Not sure, the other allele is needed to determine.
The dominant trait expressed.
The recessive trait expressed.
Answer:
The dominant trait expressed
Explanation:
For a recessive trait to be expressed, most often you require 2 recessive alleles to show the trait however if there is 2 dominant or 1 dominant and 1 recessive allele, most often the dominant trait will show. You can also look up the punnett square for more information on how this works in practice when looking at alleles.
I don't know if I should be able to get the answer then I saw ok
Long bones have which of the following structures at their ends?
epiphysis
ligaments
tendons
myofibril
Answer:
spongy bone and an epiphyseal line.
pls mar me as the BRAINLIESTAnswer:
The Epiphysis Line
Explanation:
The end of a long bone contains a spongy bone and an Epiphysis Line.
Cells blank ensure that cells are ready to progress to the next phase of the cell cycle
Checkpoint proteins ensure that cells are ready to progress to the next phase of the cell cycle.
These proteins act as gatekeepers that monitor the integrity of DNA, ensure that all required nutrients and cellular components are present, and confirm that the previous phase of the cell cycle was completed successfully. Checkpoints occur at several stages of the cell cycle, including the G1/S checkpoint, the G2/M checkpoint, and the spindle checkpoint.
If a checkpoint protein detects a problem or issue, it will pause the cell cycle, giving the cell time to resolve the issue before proceeding. This ensures that cells only divide when conditions are favorable and helps to prevent the accumulation of DNA damage or other problems that could lead to mutations or disease.
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In how many years will the population of Schuhlsville double?
250,000 inhabitants, last year there were 12,000 new children born and 10,000 people recorded deceased
Answer:
five years
Explanation:
I don't really understand what it was asking about.
Bob has the salt solutions in the list below. He does not know which is which. magnesium chloride zinc chloride copper chloride Bob also has pieces of magnesium, iron, zinc, and copper. Explain how Bob could use his materials to work out which solution is which.
What is true of the population shown in this graph?
Responses
There are no limiting factors to control population growth.
It shows the effect of overpopulation on a species.
The number of individuals will eventually drop to zero.
The population has increased until it has reached its carrying capacity.
Explanation:
sensory analysis
A population pyramid, using a paired bar chart-type graphic, shows the numbers or percentages of males and females in each age group. This type of graphic provides a very clear picture of a population's age-sex composition. It can also be used for displaying future trends in a population.
Which environmental change is most likely to affect the long-term stability of an ecosystem?
A. The extinction of sea otters, a keystone species
B. Humans using sustainable farming practices to grow food
C. An increase in the number of deer being born one spring
D. A disease that kills a few individuals in a population of trees
A. The extinction of sea otters, a keystone species, is most likely to affect the long-term stability of an ecosystem.
What is an an ecosystem?An ecosystem is a community of living organisms (plants, animals, and microbes) in conjunction with the non-living components of their environment (such as air, water, and mineral soil), interacting as a system. Ecosystems can range in size from a small pond to an entire planet.
Keystone species are species that play a crucial role in maintaining the balance of the ecosystem. When a keystone species is lost, it can have far-reaching and long-lasting effects on the entire ecosystem, often causing a chain reaction of changes that can lead to the collapse of the ecosystem.
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Trees lose water through transpiration, when water evaporates from leaves. The list describes types of tree leaves that help reduce the amount of transpiration. * small leaves
*needle like leaves, such as on conifers
* leaves with hairlike structures
* leaves with waxy coverings
Which of these is most likely observed in an area experiencing a long-term drought?
A-Trees with broad leaves will be more healthy than trees with needle like leaves
B-Trees with leaves that have waxy coverings will be more healthy than trees without wax-covered leaves
C-Trees with broad leaves will be more healthy than trees with small, flat leaves
D- Trees with leaves without any hairlike structures will be more healthy than trees with leaves covered by hairlike structures
It would be observed in areas experiencing a long-term drought that he trees with leaves that have waxy coverings will be more healthy than trees without wax-covered leaves. That is option B.
What is transpiration?Transpiration is defined as the means through which plants loses water in the form of water vapor, mainly from the stomata in leaves, but also through evaporation from the surfaces of leaves, flowers, and stems.
There are various ways plants reduce the amount of wafter lose to prevent dehydration and they include the following:
needle like leaves, such as on conifersleaves with hairlike structures leaves with waxy coveringsTherefore, when there is long-term drought, the trees with leaves that have waxy coverings will be more healthy than trees without wax-covered leaves.
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Can you compare the energy in different types of nuts?
Answer:
yes. You can compare the different energy in all nuts, the highest amount of energy comes from Brazil nuts, pecans, and macadamia nuts, followed by almonds, walnuts, hazelnuts, and pine nuts. Pistachios and cashews are the lowest.
Explanation:
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in contrast to aerobic and anaerobic cellular respiration, the ending molecule (byproduct) of fermentation is... (select one or more answers.) group of answer choices organic. an enzyme. energy poor. inorganic. energy rich.
In contrast to aerobic and anaerobic cellular respiration, the ending molecule (byproduct) of fermentation is organic.
Fermentation is the anaerobic respiration in which a carbohydrate molecule is broken down into smaller molecules such as organic acid or alcohol and releases energy.
The two types of fermentation are alcoholic fermentation and lactic acid fermentation. Alcohol fermentation, carried out by yeast, produces ethanol and carbon dioxide as byproducts, while lactic acid fermentation, carried out by some bacteria and muscle cells, produces lactic acid as a byproduct.
An example of alcoholic fermentation is the production of ethanol from glucose, and an example of lactic acid fermentation is the production of lactic acid from pyruvate.
Thus, the ending molecule (byproduct) of fermentation is organic. The byproducts of fermentation include organic compounds such as ethanol, lactic acid, and carbon dioxide. Therefore, it's an organic byproduct.
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Data table 1: lab safety equipment alternatives
(Shower or sink) (Paper towels) (Well ventilated are) (No substitution)
Eye wash staion spill containment kitm fune hood Safty gegg's
laboratory shower ______________________ __________ first aid kit
________________ kitty litter ___________________ fire extinguisher
________________ sand ___________________ spill containment kit
Shower or sink 1. Eyewash station 2. Lab shower. Paper Towels Spilt centainment. Vermiculite (hy-dorated kaminas Mg, Al iren silicate). 2. clay / Sand 3. Kitty Litter No substitution. 10 Safety goggles. 2. First aid kit 3. Fire extinguisher- 4. Spill containment kit are lab safety equipment
(Lab safety equipment alternatives)
1. Shower/Sink
Eyewash station
Laboratory shower
Drench Hoses
Self contained eye/face washes
2. Paper Towels-
Kitty litter
Sand
Spill containment kit
clay
3. Well ventilated area-
Fume hood
HEPA filters
Biosafety cabinet
Laminar flow
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Data Table 1 Lab Safety Equipment Alternatives Shower or Sink Paper Towels Well Ventilated Area No Substitution laboratory shower spill containment kit fure hood safety goggles 1 eyewash station fire extinguisher first aid kit exercise 2 Data Table 2: Sodium Hypochlorito SDS information Items SOS information
this is worth 20 points pls help
The genetic substance known as messenger RNA, or mRNA, instructs your body how to produce proteins.
What is mRNA?Messenger ribonucleic acid (mRNA) is a single-stranded RNA molecule that, in molecular biology, is read by a ribosome during the protein-synthesis process and correlates to the genetic code of a gene.
mRNA is produced during transcription, when the gene is transformed into main transcript mRNA by the enzyme RNA polymerase (also known as pre-mRNA). Introns, which are sections that won't ultimately translate for the final amino acid sequence, are typically still present in this pre-mRNA. These are eliminated during RNA splicing, leaving only exons, which are the areas that will actually make the protein. The final mRNA is composed of this exon region.
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What are the different types of massage therapies called?
petrissages
Modalities
edemas
meridians
Possible Answers:
-Aromatherapy Massage Therapy
-Craniosacral Massage Therapy
-Deep Tissue Massage Therapy
-Hot Stone Massage Therapy
-Myofascial Massage Therapy
-Pregnancy Massage Therapy
2. These geological features form when
one tectonic plate subducts under
another plate
Answer: volcanoes
Explanation:
7
(e) (i) Sucrose enters the sieve tubes in the leaves. What effect does the entry of the carbohydrate have on the water by
potential in the sieve tubes?
(ii) Explain how this effect may result in mass flow of substances in the phloem.
..[1]
Sucrose entry lowers water potential, creates pressure gradient, enabling mass flow of substances from source to sink in phloem.
(I) The section of sucrose into the strainer tubes in the leaves brings down the water capability of the arrangement in the cylinders. This is on the grounds that sucrose is a dissolvable carb that enters the strainer tubes by means of dynamic vehicle, which requires energy. The section of sucrose brings about a higher centralization of solutes in the strainer tubes, which diminishes the water potential. This makes water move into the strainer tubes from the encompassing cells by means of assimilation, bringing about a positive hydrostatic tension in the sifter tubes.
(ii) The positive hydrostatic tension made by the section of sucrose into the strainer tubes empowers the mass progression of substances in the phloem. This tension slope pushes the items in the strainer tubes, including sucrose and different solutes, from the source region to the sink region in the plant. The source is the region where photosynthesis happens, while the sink is the region where sucrose is required, like the roots or creating natural products. This peculiarity is known as mass stream or tension stream, and it considers the productive vehicle of supplements and different substances in the phloem.
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which of the following statements about polygenic inheritance are true? select all that apply. responses when a high number of genes is involved, the number of possible phenotypes is also high. when a high number of genes is involved, the number of possible phenotypes is also high. only one gene is responsible for the phenotype. only one gene is responsible for the phenotype. each gene only contributes a small part to the phenotype. each gene only contributes a small part to the phenotype. when a high number of genes is involved, the number of possible phenotypes is low.
The true statements regarding polygenic inheritance are: (A) "When a high number of genes is involved, the number of possible phenotypes is also high", and (C) "Each gene only contributes a small part to the phenotype".
The term 'polygenic inheritance' refers to a single characteristic that is controlled by the interaction of more than two genes. The inheritance of these characteristics occurs in a continuous manner as a result of the combined effects of multiple genes, rather than in an all-or-none fashion, as is the case with single-gene inheritance.
Only two of the statements about polygenic inheritance are true: (A) "When a high number of genes is involved, the number of possible phenotypes is also high, and (C) "Each gene only contributes a small part to the phenotype".
(B) "Only one gene is responsible for the phenotype.": This is an incorrect statement as multiple genes are responsible for the phenotype in polygenic inheritance.
Thus, options A and C are the correct statements about polygenic inheritance.
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Explain how a meander can form a stream
Answer:
Explanation:
A meander forms when moving water in a stream erodes the outer banks and widens its valley, and the inner part of the river has less energy and deposits silt. A stream of any volume may assume a meandering course, alternately eroding sediments from the outside of a bend and depositing them on the inside.
Asbestos is a material that was once used extensively in construction. One of the risks of working in a building that contains asbestos is the development of asbestosis. The asbestos fibers can be inhaled. Cells will phagocytose (absorb) the foreign material, but are unable to degrade it. As a result, asbestos fibers build up in which of the following cellular organelles?
a. Chloroplast
b. nucleus
c. mitochondria
d. lysosome
Asbestos fibers build up in lysosome. The correct alternative is Option d.
Asbestos fibers are unable to be degraded by cells and will accumulate in lysosomes, which are organelles that store cellular waste. The lysosomes are unable to break down the asbestos, leading to the accumulation of the material and the development of asbestosis.
Lysosomes are the organelles responsible for breaking down and digesting foreign materials within cells. However, because asbestos fibers cannot be degraded, they accumulate in the lysosomes and can eventually lead to the development of asbestosis.
Therefore The correct alternative is Lysosome. (Option d)
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How does the International Ocean Discovery Program contribute to marine science? A. It advocates for ending all drilling on the ocean floor. B. It creates international regulations for offshore drilling. C. It collects samples of sediment from the sea floor. D. It searches for the locations of oil below the sea floor.
Answer: The International Ocean Discovery Program contributes to marine science by collecting samples of sediment from the sea floor. Option C is the correct answer. The program, which involves scientists from around the world, conducts scientific ocean drilling expeditions to collect data and samples from the ocean floor, which are used to better understand Earth's history, geology, and climate.
Explanation:
Dalmatians and pugs are both the same species. However they look very different. For example, dalmatians have spots but pugs do not. What type of variation is causing this difference?
Gene variants, sometimes known as mutations, can cause genetic differences, or a natural process in which genetic information is rearranged as a cell prepares to divide can also cause genetic variations (known as genetic recombination).
There are various ways to identify genetic variation. Observations of phenotypic variation in either quantitative (traits that vary continuously and are coded for by many genes, such as leg length in dogs) or discrete (traits that fall into discrete categories and are coded for by one or a few genes, such as white, pink, or red petal color in particular flowers) traits can be used to determine genetic variation.
Protein electrophoresis, a technique for evaluating variation at the level of enzymes, may also be used to detect genetic variation.
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