Answer: Either, B or D
Explanation:
The table below shows the initial and final masses of a radioactive material whose half-life is 15 years.
Initial mass (in kilograms): 0.8
Final mass (in kilograms): 0.05
Based on the table, which of these conclusions is correct?
A.) The material decayed from 0.8 kilograms to 0.05 kilogram in 60 years.
B.) The material decayed from 0.8 kilograms to 0.05 kilogram in 30 years.
C.)The mass of the material was 0.1 kilograms after four half lives.
D.) The mass of the material was 0.1 kilograms after five half lives.
Answer:
A
Explanation:
1 half-life = .4 kg = 15 years
2 half-life = .2 kg = 30 years
3 half-life = .1 kg = 45 years
4 half-life = .05 kg = 60 years
Answer:
A
Explanation:
Initial mass is 8. The half-life is 15 years.
1st half life=.8/2=.4
2nd half life=.4/2=.2
3rd half life=.2/2=.1
4th half life=.1/2=.05
For each half life that it took it to go from .8 to 0.05, you add 15 years since that is the half life of the substance. 4*15=60.
So, the answer is A. The material decayed from 0.8 kilograms to 0.05 kilogram in 60 years.
Describe and explain how the two types of white blood cells fight pathogens? 6 mark
Answer:
White Blood Cells Defend the Body Against Disease
Neutrophils are phagocytes, cells that consume invading pathogens. Lymphocytes, the second most common type of white blood cell, disseminate through the organs and tissues of the lymphatic system. Lymphocytes target specific pathogens as part of the immune response.
Explanation:
During the photosynthetic process, glucose and what other molecule are created
durring puberty
Explanation:
Answer:
Oxygen
Explanation:
"Photosynthesis" is a process that is being used by plants in order to sustain their metabolic needs. In order to do this, it converts "light energy" into "chemical energy." There are mainly three things that are needed for the process: sunlight, water and carbon dioxide.
Sunlight (provides light energy) comes from the sun while water is drawn from the plant's roots. The light energy fuels the process. Carbon dioxide, on the other hand, is taken from the air by the plant's leaves. Once these three things are combined, they produce sugar ([tex]C_{6} H_{12} O_{6}[/tex]) and oxygen (6[tex]O_{2}[/tex]). So, the other molecule being asked above is "Oxygen."
Give one big reason why viruses are not alive
Answer: Viruses are not made out of cells, they can't keep themselves in a stable state, they don't grow, and they can't make their own energy. Even though they definitely replicate and adapt to their environment, viruses are more like androids than real living organisms.
Explanation: I think
what is 1 problem you have?
My family. They always argue with each other and I'm just there.
Answer:
I have the same problem that everyone have....CORONA VIRUS! I want it to be end by now :)
Explanation
What can you conclude about DNA from the idea that it is a cell's "brain” ?
A. it helps think.
B. it controls what cells do
C. it requires a lot of blood to operate properly
D. it is located at the top of the cell
The conclusion about DNA from the idea that it is a cell's "brain” is that it controls what cells do.
DNA:
DNA, also known as deoxyribonucleic acid, is the nucleic acid responsible for storing the genetic material of the cell. The DNA is found in the nucleus of eukaryotic cells or in the cytoplasm of prokaryotic cells. The DNA molecule produces proteins via the process of gene expression. The proteins, which acts as enzyme and hormone, controls cellular processes. Therefore, the conclusion about DNA from the idea that it is a cell's "brain” is that it controls what cells do.Learn more at: https://brainly.com/question/19365715?referrer=searchResults
1)what organs make up the organ system , the circulatory system.
2)Bone tissue are shown on the left. what is the difference between tissue and specialized cells.
Answer:
1. Circulatory system is made up of your heart, arteries, veins and capillaries.
2. There isn't a photo attached. But Specialized cells perform specialized functions in multicellular organisms. Groups of specialized cells cooperate to form a tissue, such as a muscle. Different tissues are in turn grouped together to form larger functional units, called organs.
Explanation:
Drag each tile to the correct box. COOL PICS
Arrange the organisms from fastest to slowest based on the time they’d take to complete the 20th Carnegie stage.
mouse
baboon
chicken
human
sheep
Answer:
Fastest- chicken
mouse
sheep
baboon
Slowest-human
Explanation:
Answer:
Fastest- chicken
mouse
sheep
baboon
Slowest-human
Explanation:
How can agriculture cause soil pollution?
Agriculture pollution
Explanation:
Agriculture is a main source of pollution in lake water. chemical and fertilzer
Answer:
Pesticides and fertilizers used on crops fed to animals are a major contributor to land pollution
Explanation:
hope this helps :)
Which one of the following gases is not an important component of soil?
oxygen
nitrogen
hydrogen
carbon dioxide
What gave planets in the solar system their initial speeds?
Answer:
When the cloud of gas which formed the solar system fell inwards to form the solar system, it had net angular momentum. ... The cloud that formed the solar system had angular momentum which was deposited into the velocities of planets and other bodies in orbits around the Sun (as well as the Sun's rotation).
Which plant propagation process insures some genetic diversity?
Answer:
Seed propagation takes place during sexual reproduction. The production of seeds through auto-pollination or crossed pollination ensures some genetic variation.
Explanation:
Seeds ensure the existence of genetic variation between plants. There are two general crossing systems in plants, which depend on pollination type.
Self-pollination occurs when the flower pollen is transferred to the same flower stigma, reaching that individual egg to fertilize it. These are autogamous systems. Crossed pollination occurs when the mature pollen is driven by different pollinator agents from one flower to another, reaching the other flower stigma and fertilizing its eggs. These are xenogamous systems.Sexual reproduction gives more possibilities to different alleles of a gene that did not appear in one generation to express in the next generation. Both types of pollination allow genetic variation, however by the occurrence of crossed pollination there are more chances to ensure the variability of the species and survival to environmental changes. While by self-pollination there are more chances to express the same genotype of the parental plant. The Xenogamous system has the advantage of avoiding the effects of endogamy in a population.
How many factors should a well-designed experiment test at one time?
Answer:
Depends on the number of experiment variables.
Explanation:
You should only test one variable/factor
WHY IS A FOSSIL FOUND IN MULTIPLE LAYERS OF ROCK (TIME PERIODS) NOT CONSIDERED A RELIABLE INDEX FOSSIL?
NOT SURE IF THIS IS RIGHT PLEASSSEEEEWEEE HELPP
Its false
Because each organism some has same needs or different needs.
When humans breed organisms, they are selecting variations that occur naturally in populations.
True or false ?
Answer:
TRUE!!!
Explanation:
Artificial selection, often known as "selective breeding," is when people choose animals or agricultural products based on desirable features, hence it is a true statement.
What is Artificial selection?Different phenotypes can be introduced into an organism via genetic changes that change gene activity or protein function.
Natural selection is the process of identifying advantageous traits in plants and animals and taking actions to improve and perpetuate those traits in subsequent generations.
If a trait is advantageous and aids an individual in surviving and reproducing, the genetic variation is more likely to be passed to the next generation.
Therefore as opposed to letting the species evolve naturally without human intervention, as in the natural selection, hence it is a true statement.
Learn more about selection, here:
https://brainly.com/question/1306974
#SPJ2
Do anyone why blood is red?
Answer:
Human blood is red because of the protein hemoglobin, which contains a red-colored compound called heme that's crucial for carrying oxygen through your bloodstream.
Blood gets its bright red color when hemoglobin picks up oxygen in the lungs
the oxygen essentally makes it red
Explanation:
According to Vince Carter, "...the most important aspect of getting his degree was the sense of accomplishment it brought. " Use information from the selection and your own ideas to explain what he meant by this statement.
Answer:
the hard work he went through
What is a GMO and why are GM foods controversial?
Answer:
Genetically modified organism
Explanation:
They are controversial because since they are still so new, we don't know what they will do long-term. They have been said to cause allergic reactions.
The dodo bird is now extinct. What factor would not have led to its extinction?
Answer:it was well adapted to living on the island of Mauritius
Explanation:
Unzips the DNA strand by breaking hydrogen bonds
What are some of the things that Vincent had to do to enhance his genetic
"imperfections?" so that he looked like the real Jerome? GATTACA
Answer:
Lengthen his legs and straighten his teeth.
Explanation:
Vincent had done surgery to lengthen his legs and straighten his teeth in order to enhance his genetic imperfections because he has short legs and improper teeth. He also had some other diseases such as heart disorder, neurological disorder, manic depressive and attention deficit disorder. These disorder can't be cure because it occur to him genetically.
Describe the process of absolute dating as it relates to igneous rock and the fossil record.
Answer:
Radiometric dating. Geologists use radiometric dating to estimate how long ago rocks formed, and to infer the ages of fossils contained within those rocks. ... When molten rock cools, forming what are called igneous rocks, radioactive atoms are trapped inside. Afterwards, they decay at a predictable rate.
Dr. Fatima was investigating the pathways in photosynthesis. She observed a set of chemical reactions whereby electrons were getting excited and energy carriers were being made and water was splitting. What process was she observing?
A. Krebs cycle
B. Light Reactions
C. glycolysis
D. Calvin cycle
What are the advantages and disadvantages to produce few offspring that are extensively cared for and protected?
In mature animals when do cells still need to differentiate?
Answer:
As an organism develops, cells differentiate to form different types of cells. Most types of animal cell differentiate at an early stage. Many types of plant cells retain the ability to differentiate throughout life. In mature animals, cell division is mainly restricted to repair and replacement.
Explanation:
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In mature animals cells differentiate during : Repair and replacement of animal cells
Cells differentiate in organisms and plants to create more cell types, as the organism and plants continue to mature. While cell differentiation in animals occur mostly before maturity, plants cells continue to differentiate until they die.
While in mature animals, cells differentiates at maturity only when the cells of the mature animal needs repair or replacement due to damage caused to the a cell or tissue.
Hence we can conclude that in mature animals cells differentiate during repair and replacement of cells.
Learn more : https://brainly.com/question/19015367
Wyatt has heart problems
Answer:
If Wyatt has heart problems, Wyatt can eat healthy foods to try and decrease the problems, Wyatt can also make sure that his weight and blood pressure isn't to high. Wyatt can try to get seen at the hospital to make sure everything is fine.
Your teacher takes a candle and cuts some wax from the bottom of it. She puts the bit of wax in a beaker and places it on a hot plate. Eventually, the wax melts and becomes liquid. Do you think this is a physical or chemical change?
Answer:
Chemical
Explanation:
Who is to blame climate change?
Scientists have measured global temperatures for over a hundred years and see that the Earth is getting hotter. Ice core data suggests the Earth should actually be cooling if it were following its natural cycles. The trend can be best visualized by comparing each year’s average temperature with the long- term average. Figure 1 shows observations of the world’s annual average temperature made by the National Oceanic and Atmospheric Administration (NOAA). In recent decades, the years have always been hotter.
Over geologic time, the Earth’s average temperature has changed as a result of the sun’s output, the tilt and position of the Earth in its orbit, and the concentration of greenhouse gases. Scientists have developed a good understanding of the natural variations in these factors by examining different data sources in order to estimate ancient temperatures. Observations tell us that these natural factors have not been changing over the last hundred years or so in a way that would explain the observed temperature increases.
In contrast, greenhouse gases have been changing in a way that can explain the observed temperature increases. Figure 2 shows the change in atmospheric CO2 concentration over the last thousand years. At the Scripps Institute of Oceanography in Hawaii researchers have been sampling pristine mountaintop air every month since 1958. Their observations show that both the concentration and isotopic composition of CO2 is changing, and is consistent with manmade sources, including the carbon emissions from burning fossil fuels. The industrial revolution marked a drastic increase in CO2 concentrations in the atmosphere when humans began using fossil fuels on a large scale.
Scientists attribute the global warming trend observed since the mid-20th century to the human expansion of the "greenhouse effect"1 — warming that results when the atmosphere traps heat radiating from Earth toward space. Certain gases in the atmosphere block heat from escaping. CO2 along with other gases are known as greenhouse gases. Over the last century the burning of fossil fuels like coal and oil has increased the concentration of atmospheric CO2. In its Fifth Assessment Report, the Intergovernmental Panel on Climate Change, a group of 1,300 independent scientific experts from countries all over the world under the auspices of the United Nations, concluded there's a more than 95 percent probability that human activities over the past 50 years have warmed our planet.
Give evidence and reasoning!!
Answer:
People
Explanation:
The energy we use and waste
A student placed a small chip of limestone into a hydrochloric acid solution, and carbon dioxide gas was released. The carbon dioxide provided evidence that
A. The formation of an element occurred.
B. Only a physical change occurred.
C. A chemical change occurred.
D. Only a loss of mass occurred.
C. A chemical change occurred.