Answer:
Explanation:
They have developed a resistance to the active killing ingredient of the pesticide. Their immune system has figured out how to deal with the active ingredient. Apparently it is an example of survival of the fittest. They are able to pass that quality along to their offspring.
Fish respiratory systems exchange gas and receive oxygen at the gills. This oxygen then enters the blood stream and is pumped through the heart and back through the gills without first returning to the heart. This order of events best describes which type of circulation system?
a) double loop
b) single loop
c) open
d) recycling
the answer is single loop
Answer:
b) single loop
Explanation:
In fishes, deoxygenated blood is carried to the heart which in turn pumps it to the gills for exchange of gases. Oxygenated blood is delivered from gills to the body parts.
As per given information, fishes exhibit a single loop circulatory system. If the blood passed through the heart only once during one loop of circulation, the system is said to be single loop circulation.
Identify the interaction described below. One organism benefits while the other is killed. Two species need the same resource, which is limited.
One organism benefits while the other is killed. Two species need the same resource, which is limited. The interaction described is called competition.
In competition, two or more organisms require the same limited resource, such as food, water, space, or sunlight.
Both organisms compete for access to the resource, and as a result, one organism may outcompete the other, leading to its successful acquisition of the resource while the other organism is deprived and may ultimately die or experience reduced fitness.
Competition plays a crucial role in shaping ecological communities and driving the evolution of species. It can drive adaptations and lead to the development of specialized traits that allow organisms to better exploit resources or avoid direct competition.
Through competition, species can influence each other's distribution, abundance, and community structure.
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Final answer:
The interaction described is a combination of two types: predation or parasitism and interspecific competition. The former involves a clear beneficiary and a victim, while the latter is a struggle over limited resources, negatively impacting both species involved.
Explanation:
The scenario described where one organism benefits while the other is killed, and two species need the same resource, which is limited, refers to two different types of interactions: predation or parasitism, and interspecific competition, respectively. Interspecific competition occurs when two species compete for the same limiting resources in their ecosystem. This competition can lead to one species outcompeting the other, possibly resulting in the exclusion or adaptation of the lesser competitor. This interaction plays a significant role in natural selection.
On the other hand, predation involves one species killing and eating another, while parasitism involves one species benefiting at the expense of the other, potentially without immediate death. In competition, even the 'winning' species suffers costs from the energy and resources expended in the process, leading to a negative impact on both participants.
Trilobites were abundant in Pennsylvania. Trilobites were among the first of the arthropods, a phylum of hard-shelled creatures with multiple body segments and jointed legs. Their fossils first appeared in early Cambrian period about 570 million years ago. The trilobite fossils show that during most of this time Pennsylvania was ___________ providing favorable conditions for the trilobites.
A) glacial terrain
B) a dry and sandy plain
C) mostly mountain ranges
D) covered by warm, shallow seas
Answer:
The answer is D)
The trilobite fossils show that during most of this time Pennsylvania was covered by warm, shallow seas providing favorable conditions for the trilobites.
What is Pennsylvania?
One of the original 13 American colonies, Pennsylvania, formally known as the Commonwealth of Pennsylvania, is a state that makes up the United States of America.
The state is somewhat rectangular in shape and spans 150 miles (240 km) in the north and 150 miles (480 km) in the east. Its northern and eastern borders are Lake Erie and New York State; its western and southern borders are the West Virginia panhandle and Ohio. Its eastern and southern borders are Delaware, Maryland, and West Virginia.
The state's capital is Harrisburg, which is located in the Appalachian Mountains' foothills. Pennsylvania, along with New York, New Jersey, Delaware, and Maryland, is categorized as a Middle Atlantic state.
Therefore, The trilobite fossils show that during most of this time Pennsylvania was covered by warm, shallow seas providing favorable conditions for the trilobites.
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Match each biodiversity problem with the most appropriate solution
Answer:
1. A large highway prevents yellow-spotted salamanders from traveling to their breeding grounds - Construction of wildlife corridor
2. The hawksbill sea turtle is in decline because of excessive hunting and exploitation - Classifying the species as endangered
3. A population of channel catfish is threatened by a high level of pollution in a river - Bioremediation
4. The loss of vegetation in a forest reduces the survival rate of eastern bluebirds - Reforestation
Explanation:
The pants and animals are facing lot of dangers and threats because of the human activities, so there are numerous methods that can be used in order to protect and preserve them as part of nature. The construction of wildlife corridors is a very nice method that enables the animals to move freely from one part to another of their habitat, and not be in danger of getting hit by a vehicle. Classifying a species as endangered is useful when species needs protection, as with this action the species will be protected by law, so that will significantly reduce or eliminate the threat. Bioremediation is a method used to get certain habitat into its initial healthy natural form and composition, and this method is crucial when it comes to preserving the species in polluted habitats. One of the biggest problems is the deforestation because the forests are the basis for the survival of the majority of organisms. The solution for that is the reforestation, which is simply a method through which new young saplings are planted on the places where the old trees have been eliminated.
1, A large highway prevents yellow-spotted salamanders from traveling to their breeding grounds - Construction of wildlife corridor
2. The hawksbill sea turtle is in decline because of excessive hunting and exploitation - Classifying the species as endangered
3. A population of channel catfish is threatened by a high level of pollution in a river - Bioremediation
4. The loss of vegetation in a forest reduces the survival rate of eastern bluebirds - Reforestation
Explanation:
plato
2. What were the earliest organisms to evolve?
Answer:
Both bacteria and blue algae are prokaryote organisms, meaning that they do not have a differentiated nucleus, and therefore they are more primitive. But blue algae are able to perform photosynthesis and so we can believe that the first forms of life on Earth date even further back than 3 and a half billion years ago.
Explanation:
The earliest organisms to evolve were single-celled prokaryotes such as bacteria and archaea. These organisms emerged around 3.5 billion years ago and played a crucial role in the development of more complex forms of life.
Explanation:The earliest organisms to evolve were single-celled prokaryotes such as bacteria and archaea. These organisms are believed to have emerged on Earth around 3.5 billion years ago. They were able to survive and thrive in diverse environments, leading to the development of more complex forms of life over time.
For example, cyanobacteria, a type of bacteria, played a crucial role in the evolution of our atmosphere by producing oxygen through photosynthesis. This paved the way for the emergence of more complex organisms, including eukaryotes.
Overall, the early organisms that evolved were simple and unicellular, laying the foundation for the diversity of life we see today.
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3 main components of dna molecules
The three main components are phosphate, deoxyribose, and four nitrogenous bases
The deoxyribose is a sugar
and the the 4 nitrogen bases are adenine, guanine, cytosine, and thymine.
The circulatory system works best with which other body system to supply the body’s cells with the nutrients they need?
Answer: fins
Explanation:
Answer:
the digestive system
Explanation:
The circulatory system has always worked with the digestive system because digestive system makes sure when you eat food it gets broken down and out of your body and circulatory circles everything around with veins and arteries.
Meiotic cell division results in gametes that produce sperm and egg cells by-
Answer:In contrast to a mitotic division, which yields two identical diploid daughter cells, the end result of meiosis is haploid daughter cells with chromosomal combinations different from those originally present in the parent. In sperm cells, four haploid gametes are produced.
Explanation:
Meiotic cell division plays a critical role in the production of gametes, which are sperm and egg cells. This process which involves one round of DNA replication and two rounds of cell division results in four haploid cells from an original diploid cell, significantly contributing to genetic diversity in human reproduction.
Explanation:Meiotic cell division results in the production of gametes, specifically sperm and egg cells, through a process known as gametogenesis which includes spermatogenesis and oogenesis. The process begins with a diploid cell, which undergoes meiotic cell division to create haploid cells. These cells contain half the number of chromosomes as the original cell (23 instead of 46 in humans).
In the first stage of meiosis, the 23 pairs of chromosomes separate, creating two cells. During the second stage of meiosis, each of the 23 replicated chromosomes divides, again. This results in four cells each having half the number of chromosomes, thereby leading to the formation of haploid cells, specifically spermatids in sperm.
Finally, a process called spermiogenesis transforms these spermatids, reducing the cytoplasm, and starting the formation of true sperm. The creation of eggs, or oogenesis, follows a similar process. These processes are essential steps in human reproduction and genetic diversity.
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what type of cloud is puffy
Answer:
Cumulus is the cloud that resembles a puffy thing.
Explanation:
PLEASE MARK AS BRAINLIESTAnswer:
puffy cloud is discussed below.
Explanation:
Cumulus is the puffy, white, cotton-top clouds that resemble so fluffy that you imagine angels resting around and preparing their impression on them. They are estimated low-level clouds, but some patterns can develop up past 21,000ft. Cumulus appears in several categories, and here are only a few.Chargaff's rule states that the amounts of guanine and cytosine are roughly the same, and the amounts of adenine and thymine are roughly the same
A. in eukaryotes only. The rule doesn't apply to prokaryotes.
B. but the relative amounts of G+C and A+T vary by species.
C. except in species that use uracil in place of thymine in their DNA.
D. and the relative amounts of G+C and A+T don't vary by species.
Answer:
B.
Explanation:
This is because of the base pairing rule in DNA. Guanine (G) pairs with Cytosine(C) while Adenine(A) pairs with Thiamine (T). Therefore, the amount of G will relatively be generally equal l to that of C while that of A will be generally equal to that of T.
Chargaff's rule states that in a species' DNA, the amounts of adenine and thymine are roughly the same, as are the amounts of guanine and cytosine. The rule applies to both eukaryotes and prokaryotes. However, the relative proportions of A+T compared to G+C can vary significantly between species.
Explanation:Chargaff's rule, named after biochemist Erwin Chargaff, tells us that in DNA the amounts of guanine (G) and cytosine (C) are roughly the same, and the amounts of adenine (A) and thymine (T) are approximately equal. This applies to both eukaryotes and prokaryotes. The correct response to your multiple choice question is option B: 'the relative amounts of G+C and A+T vary by species'.
For example, some species may have a higher proportion of A+T compared to G+C, or vice versa. However, within a species, the G≈C and A≈T relationships hold true. Note that this rule calculates relative quantities of these nucleotides within the entire genome and not per single DNA strand.
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In a type of chemical reaction called thermal decomposition, heat is added to a substance, which then splits apart to form several new substances.
What type of chemical reaction is a thermal decomposition reaction?
A. organic
B. synthetic
C. exothermic
D. endothermic
The answer is D.
An endothermic reaction involves absorbing heat whereas an exothermic involves releasing heat.
How and why does the population change over time using natural selection
Answer:
Explanation: Natural selection is a cause of evolution. So over time, organisms can start to evolve due to artificial selection. Natural selection, sometimes referred to as "survival of the fittest," is a mechanism for the evolution of a population to become better adapted for survival in a specific environment. This means that organisms with traits that are best suited for the environment will pass these traits to their offspring.
Below is a food chain from an ecosystem.
fly → frog → snake → alligator
The arrows indicate the direction of the flow of
water.
carbon dioxide.
oxygen.
energy.
Answer:
I think the answer is D.
ENERGYYYExplanation:
What's the middle layer of the ocean known as?
A. Pycnocline
B. Mesocline
C. Mixed layer
D. Deep ocean
Answer:I think it is 'A'
Explanation:
Because when mesocline is a really a known word. Also, when you search what it is. It is a different word. Mixed layer obviously doesn't make sense. And deep ocean most likely mean the trenches. But pycnocline is a layer in an ocean in which the density increases rapidly with depth. P.S. sorry if I'm wrong. This is the best I can give you.
Pynocline is the middle layer of ocean. Thus, option A is correct.
What are different types of ocean layer?Study of oceans is known as oceonography & oceonographers ( scientist who study the ocean ) divided the ocean into several part from top to bottom i.e in horizontal layers.
The characteristics which distinguish the the ocean into different layers are temperature, density and amount of light at different depth to classify these layers. The most important factor is density of water which is determined by salinity of water.
Oceonographers are generally categories the ocean into four layer:-
1:- Epipelagic zone
This zone refers to the surface of the ocean where light penetrates first.
2:- Mesopelagic Zone
The mesopelagic zone is found from 150mtr to 1000mtr below the surface also called as twilight zone
3:- Bathypelagic Zone
This zone is found from 1000mtr to 4000mtr below the surface of ocean in thus region light is not exist.
4:- Abyssopelagic Zone
This zone is found from 4000mtr to the surface of seafloor in this zone water are nearly freezing and pressure are immense.
Therefore, pynocline is the middle layer of ocean. Thus,option A is correct.
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what is a natural source of sulfur dioxide,carbon dioxide,and Ash in the atmosphere
Answer: Volcanoes/volcanic activity
Explanation:
Which is an example of renewable resources
Final answer:
Wind is a renewable resource that can be replenished naturally at a pace that matches or exceeds its usage by humans, making it sustainable and inexhaustible. Other examples are sunlight and tidal movements, all harnessed for alternative energy sources.
Explanation:
An example of a renewable resource is wind. Wind is a natural resource that is replenished by natural processes at a rate that is equal to or faster than it is consumed by humans. It is harnessed through wind turbines for energy development and is considered an alternative energy source that is sustainable and in no danger of being used up. Other examples of renewable resources include sunlight, which can be captured for solar power, and the movement of ocean tides, which can also be tapped for energy.
Unlike nonrenewable resources such as coal, which exist in fixed amounts and can be depleted, renewable resources like wind, sunlight, and the kinetic energy of water can be utilized repeatedly without running out. In addition to wind and solar energy, sustainable materials like wood, cork, bamboo, and certain crops can be considered renewable if they are managed in a way that allows them to regenerate and meet the needs of both present and future generations.
In the chart, the recessive trait is
can you please post the chart?
Answer:
In the chart, the recessive trait is
A) no teeth.
B) sex-linked.
C) small teeth.
D) large teeth.
Explanation: Here is the chart.
patrick recently married a cute star girl patti he is considered a purebred for his tall head shape (T) which is dominant over a short head(t) if patti is a short headed starlady what type of heads would their children have.
Answer:
Al children would have a Tall head shape
Explanation:
Patrick is purebred for the dominant tall head shape so his genotype would be TT. Patti on the other hand is short headed, which is recessive, so the only possible genotype would be tt. If we put that in a Punnet, you can see the result:
TT x tt
T T
t Tt Tt
t Tt Tt
Since all the results are Tt, that means the tall head shape would be expressed because it is dominant and it will mask the recessive trait. So the answer would be:
All children would have a tall head shape.
1. Is this statement true or false?
Living things are classified by the characteristics they have in common.
2. There are seven major levels of classification. Kingdom and Phylum are just two of the levels.
Which choices are also major levels of classification?
Choose all answers that are correct.
Class
Order
Family
Level
3. Which choices are also major levels of classification?
Choose all answers that are correct
Genus
Species
Group
Answer:
1. True
2. class-order-family
3. genus-species
Explanation:
Final answer:
True, living things are classified by common characteristics. The levels of classification include Kingdom, Phylum, Class, Order, Family, Genus, and Species. 'Class', 'Order', and 'Family' are correct answers; 'Homo sapiens' is the binomial name for humans; and a 'kingdom' is a taxon within a domain.
Explanation:
1. The statement that living things are classified by the characteristics they have in common is true. Living organisms are grouped based on shared features, which helps scientists communicate about them and better understand their relationships and evolutionary history.
2. The seven major levels of classification include Kingdom, Phylum, Class, Order, Family, Genus, and Species. Therefore, Class, Order, Family are also major levels of classification, whereas 'Level' is not a recognized category in this context. Genus and Species are the two other levels alongside the ones mentioned.
3. In the binomial nomenclature, Homo sapiens is the correct scientific name for humans, where Homo is the genus and sapiens is the species.
4. A kingdom is correctly defined as a taxon within the broader category of a domain.
5. Lastly, similar classes are grouped into a Phylum in the Linnaean system of classification.
What makes water a polar molecule?
A. The liquid nature of water B. The equal forces between oxygen and hydrogen C. The ionic bond between oxygen and hydrogen D. The uneven bend in the bond between oxygen and hydrogen
The uneven bend in the bond between oxygen and hydrogen makes water a polar molecule.
Further ExplanationPolar molecules
Polar molecules result from a difference in electronegativity between bonded atoms. For example in water the bonded atoms of oxygen and Hydrogen have a difference in electronegativity such that oxygen is partially electronegative while hydrogen is partially positive. Atoms in a polar molecule do not share electrons equally in a covalent bond. In a polar molecule such as water molecule, a dipole is formed with one part of the molecule carrying a partial positive charge while the other carries a partial negative charge. Dipole forms when there is a difference in electronegativity of each atom in a polar molecule.Examples of a polar molecules;
Ethanol; between hydrogen and oxygen atom. Water; between hydrogen and oxygen atoms Ammonia; Nitrogen and hydrogen atoms Non-polar molecules These are molecules that have atoms sharing electrons equally in a diatomic molecule. In these molecules there is no net electrical charge across the molecule. Non polar bond forms when the difference in electronegativity between atoms is less than 0.5. They also form when atoms sharing a polar bond are aligned in such a way that the net electric charge is zero. Examples of non-polar molecules include; noble gases, such as He, carbon dioxide, methane, benzene, etc.
Keywords: Polar molecules, non-polar molecules, dipole, polar and non-polar bond
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Level: High school
Subject: Chemistry
Topic: Structure and bonding
Sub-topic: Polar and Non-polar bond
D. The uneven bend in the bond between oxygen and hydrogen makes water a polar molecule.
Water is a polar molecule because of the uneven distribution of electron density within its chemical bonds. In a water molecule, two hydrogen atoms are covalently bonded to one oxygen atom. Oxygen is more electronegative than hydrogen, meaning it has a stronger pull on shared electrons in the covalent bonds.
As a result, the oxygen atom pulls the shared electrons closer to itself, creating a partial negative charge (δ-) around the oxygen atom and partial positive charges (δ+) around the hydrogen atoms. This uneven distribution of charge results in a dipole moment, where one end of the molecule has a partial positive charge, and the other end has a partial negative charge.
The bent shape of the water molecule also contributes to its polarity. Due to the two lone pairs of electrons on the oxygen atom, the H-O-H bond angle is approximately 104.5 degrees. This bent molecular geometry further enhances the unequal sharing of electrons between oxygen and hydrogen, reinforcing the polar nature of water.
Water's polarity is crucial for its unique properties and behavior. It enables water molecules to form hydrogen bonds with each other and with other polar molecules, leading to properties such as high surface tension, high specific heat, and excellent solvent capabilities. These properties are essential for life as we know it, as they play a vital role in various biological processes and the functioning of ecosystems.
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which process is occurring in this photograph of a glacier?
please and thanks!
Answer:
The correct answer is option A, that is, plucking.
Explanation:
Quarrying also considered as plucking refers to a glacial process, which is accountable for the transportation and erosion of the single fragments of bedrock mainly the large joint blocks. With the movement of the glacier down in a valley, the friction makes the basal ice of the glacier to infiltrate and melt the joints in the bedrock.
Which structure(s) carry oxygen-rich blood away from the heart? - arteries -veins -ventricles -atria
Answer:
Arteries carry oxygen-rich blood away from the heart.
Explanation:
Blood vessels are part of our circulatory system and help in the blood distribution in whole body. There are 3 types of Blood vessals.
1. Arteries
2. Veins
3. Capillaries
Arteries are the vessels that carry the oxygen rich blood from the heart to the other parts of the body. While veins have the de-oxygenated blood. Capillaries are very small vessels that are the site of transfer between cell and blood. Nutrients from blood for example glucose are transferred to the cells.
Which of the following is a process during meiosis that leads to genetic variation?
A.
cellular material replicates before separation
B.
the nuclear envelope breaks down within the cell
C. genes independently separate from one another
D. DNA organizes into chromosomes within the nucleus
Reset
I’m pretty sure the answer is D I might be wrong though
An influx of some pollutants, such as fertilizers and pesticides, into bodies of water can lead to artificial____ a) fertilization b) population decline c)selection d) eutrophication
Answer:
The answer is C Selection
PLEASE MRK ME BRAINLIEST
Explanation:
Radio waves are a part of the electromagnetic spectrum with high waves links and low frequencies.
A. true
B. false
The answer is:
A. true
Answer: True, radio waves are part of the electromagnetic spectrum with high wave links and low frequencies. I attached a picture of the electromagnetic spectrum for your reference.
Hope this helps ya :D
what is the large brand of muscle that controls the size of the chest activity
Answer:
Diaphragm
Explanation:
The diaphragm because it controls the size of the chest cavity using the lungs.
Hope This Helps!
It's the Diaphragm hope I got it right
A scientist is studying a form of marine bacteria growing in culture dishes. He noticed that a clear area formed around the mold where the bacteria that had grown in this area died (this is now referred to as a zone of inhibition). In the culture dishes that had no mold, no zones of inhibition were present. Formulate a valid hypothesis based on his observations.
A. The temperature in the lab was too cold for the mold to grow.
B. The mold must be producing a chemical that killed the bacteria.
C. The bacteria must be producing a chemical that killed the mold.
D. The temperature in the lab was too cold for the bacteria to grow.
Answer:
B. The mold must be producing a chemical that killed the bacteria.
Explanation:
This is a commonsense explanation rather than a scientific explanation but, it can't be A or B since that makes no sense... and C wouldn't be correct because the bacteria dies and if the answer would be C then why did the bacteria die if the bacteria killed the mold?
The answer would be B :)
Please Help!
How do various types of infectious agents respond to the use of antibiotics?
A. Viruses respond to antibiotics; bacteria do not.
B. Bacteria respond to antibiotics; viruses do not.
C. Both bacteria and viruses respond to antibiotics.
D. Neither bacteria nor viruses respond to antibiotics.
Im pretty sure it's not D.
Answer:
c
Explanation:
The reason being that a virus is spread, like influenza. You cant kill this, but when you have a stomach bug, most of viruses are killed, but a lot of bacteria is also killed
As bacteria respond to antibiotics and viruses do not, option B. is the correct option.
How do bacteria respond to antibiotics and viruses do not?Antibiotics can not kill viruses because viruses have different physical structures and are known to replicate in a different way than bacteria.
Antibiotics work by targeting the growth machinery in bacteria and not viruses which kills or inhibit that particular bacteria.
Talking about it structurally, an antibiotic can not kill a virus with a completely different replicating “action”.
Hence, as bacteria respond to antibiotics and viruses do not, option B. is the correct option..
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Consider the model of the oxygen cycle as it moves through the various spheres of Earth. One assumption we can make after analyzing the model is that
A) the majority on the oxygen on Earth is stored in the lithosphere and is the result of weathering.
B) photosynthesis releases oxygen into the atmosphere while aerobic respiration removes oxygen from the atmosphere.
C) oxygen is added from the atmosphere when plants undergo photosynthesis and is removed from the atmosphere by animal respiration.
D) the inputs and outputs of the oxygen cycle are equal and opposite to the inputs and outputs of carbon dioxide in the carbon cycle
Answer:
B)Photosynthesis releases oxygen into the atmosphere while aerobic respiration removes oxygen from the atmosphere.
Explanation:
Only option B satisfies the answer to the question.
We know that photosynthesis is the process whereby green plants manufacture their foods in the presence of carbon dioxide and sunlight. Carbondioxie in the environment is used to manufacture food in plants. The bye product of photosynthesis is oxygen gas. Oxygen gas is used for aerobic respiration in animals and is essential for their life. This way photosynthesis adds to the pool of oxygen in the atmosphere and aerobic respiration removes from the pool.
Answer:
B
Explanation:
it's the only answer that fully answers this question. and i took the test
what has occurred when DNA overloads in a cell
Answer:
When the cell becomes too large, the DNA cannot keep up with demands.
Explanation:
What is DNA Overload :
As the cell grows, the demands are placed on the cell's DNA. If this ratio gets too low, the cell cannot efficiently move materials in & out of the cytoplasm. This process is called DNA overload.
THE CELL CYCLE
Cell cycle is a series of cellular events during which the cell grows, prepares for division & then divides.
Cell Growth and Division
When the cell becomes large, DNA and the more trouble the cell has moving enough nutrients and wastes across the cell membrane.