Structured questions
In an experiment on the action of the enzyme amylase, equal volumes of enzyme and starch
solution were mixed. The quantity of maltose (product) was measured during two separate
experiments, one at 18 °C, the other at 25 °C. The results are shown in the graph below.
1.
a.
b.
C.
quantity of maltose produced
(arbitrary unit)
12.
10-
8.
0 2 4
6
25 °C
18 °C
8 10 12 14 16 18
time (min)
Explain why the quantity of maltose produced eventually levelled off at both
temperatures.
[1 mark]
Explain why, at 4th minute time, more maltose had been produced at 25 °C than at 18 °C.
[4 marks]
In terms of the properties of enzyme, explain why amylase is the only enzyme that breaks
down starch.
[1 mark]
Answers
1) The levelling is due to the attainment of saturation point
2) The production of more maltose show that 25 °C is the optimum temperature of the enzyme.
What is an enzyme?An enzyme is a biological catalyst that see to the speeding up of the chemical reactions that occur in the body. Recall that an enzyme must be specific in its action. This implies that no two enzymes are able to catalyze the same reaction. The owes largely to the fact that the enzyme fits with the substrate in a lock and key model.
Let us recall that us recall that an enzyme does have an optimum temperature at which it functions, At the optimum temperature of the enzyme, the productivity of the enzyme is highest.
It then follows that;
1) The enzymes level off in the both curves because it has reached the saturation point.
2) The at 4th minute time, more maltose had been produced at 25 °C than at 18 °C because 25 °C is the optimum operating temperature of maltose
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Related Questions
Who narrated the movie “fuel”
Answers
Answer:
upupfo6ffuucfycuitxouxyoxyoufpfoyxyoxypc
select components of biodiversity. multiple select question. ecosystems in which species live relative abundance of species reproduction rates of species number of species genetic variability of species potential for human benefit from species
Answers
The components of biodiversity are genetic variability, relative abundance, ecosystems, and number of species. The correct options are A, B, D, and E.
What is biodiversity?Biodiversity corresponds to the wide range of life that can be encountered in a particular region, including living creatures, plants, yeasts, and perhaps even pathogens such as bacteria.
Each of these lifeforms and living things collude in ecosystems to find equilibrium and survive in the wild, much like an elaborate system.
Biodiversity refers to the variability of living organisms from all sources, including terrestrial, marine, and other aquatic ecosystems, as well as the ecological complexes of which they are a part.
It includes diversity within species, diversity between species, and diversity of ecosystems.
Genetic variability, relative abundance, ecosystems, and the number of species are all components of biodiversity.
Thus, the correct options are A, B, D, and E.
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which list contains an item that does not belong with the others? please choose the correct answer from the following choices, and then select the submit answer button. answer choices sympathetic nervous system, increases heart rate, slows digestion parasympathetic nervous system, increases respiration, stimulates digestion sympathetic nervous system, dilates pupils, relaxes bladder parasympathetic nervous system, contracts pupils, stimulates blood flow to the genitals
Answers
Answer: parasympathetic nervous system increase respiration stimulates digestion
Explanation:
i took one for the team
Parasympathetic nervous system, increase respiration and stimulates digestion sympathetic nervous system are the list contains an item that does not belong with the other.
What is parasympathetic nervous system?It very well may be called your "programmed" sensory system, as it's answerable for some capabilities that you don't need to contemplate to control. This can incorporate control of your pulse, circulatory strain, absorption, pee and perspiring, among different capabilities.
The parasympathetic piece of your autonomic sensory system adjusts your thoughtful sensory system. While your thoughtful sensory system controls your body's "survival" reaction, your parasympathetic sensory system assists with controlling your body's reaction during seasons of rest.
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pacinian corpuscles - deep pressure and vibration meissner corpuscles - light touch merkel cells (discs) - deep pressure and texture ruffini endings - stretch ree nerve endings - pain and temperature
Answers
An onion-shaped nonneural (connective) tissue structure called a Pacinian corpuscle is built around a nerve ending to lessen the mechanical sensitivity of the nerve terminal itself.
One of the four main types of mechanoreceptors (specialized nerve endings with adventitious tissue for mechanical sensing) found in mammalian skin is the Pacinian corpuscle, also known as the lamellar corpuscle or the Vater-Pacini corpuscle. Both hirsute (hairy) and glabrous (hairless) skin, viscera, joints, and the periosteum of bone include this type of mechanoreceptor, which is principally in charge of sensitivity to vibration. A small number of them are also susceptible to low frequency or quasi-static pressure stimuli. The majority of them only react to abrupt perturbations and are particularly sensitive to vibrations at frequencies under a few hundred Hz. The vibrational role could be utilized to distinguish between smooth and rough surfaces, for example. A large portion of Pacinian corpuscles functions as quickly adapting mechanoreceptors.
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In a cell, the selective permeability of the cell
membrane is most closely associated with the
maintenance of
A. homeostasis
C. phagocytosis
B. hydrolysis
D. pinocytosis
Answers
In a cell, the selective permeability of the cell membrane is most closely associated with the maintenance of homeostasis.
What is the selective permeability of cells?
The selective porousness of the cell membrane is its ability to distinguish between different types of molecules, allowing some to pass while restricting others. The natural membrane diffusion rates of some chemicals have some bearing on this selectivity.
Describe homeostasis.
Physiological state is the propensity of a biological system to maintain stability while responding to environmental factors that are ideal for survival. Life continues if the physiological state is attained; if not, tragedy or death occurs. The stability attained can be a dynamic equilibrium, in which the majority of the conditions are uniform yet change is constant.
Thus, to keep up the stable conditions of the cell atmosphere the selective porousness of the cell is maintained so solely an exact quantity of drugs will go within the cell so stable conditions of the cell square measure maintained.
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a(n) period is a brief time following a nerve impulse when the membrane is unresponsive to an ordinary stimulus.
Answers
A refractory period is a brief time following a nerve impulse when the membrane is unresponsive to an ordinary stimulus.
What is refractive period?The refractory period occurs just after the ongoing the intercourse come to an ends.
It implies to the time in between having an release also the feeling ready to be intercourse arises again. It is also referred to as the resolution stage.
This physiological response is basically accompanied by a psychological refractory period in which the individual is usually not that much indulged in intercourse.
Oxytocin, also the one acting as the bonding chemical, as it is experienced by females either after intercourse or during maternal activities like one as childbirth and feeding, can aids in relaxation in men, contributing to the contentedly initial state after release.
The brief time after a nerve impulse is referred as refractory period when the membrane is unresponsive to an ordinary stimulus.
Thus, the answer is refractory period.
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um has a faulty lac operon in which there is a structural defect in the operator. in this bacterium: a. there is a mutation in a segment of dna that binds a promoter. b. a missense mutation is found in the gene that codes for the repressor. c. there is a structural problem with a segment of dna that binds a repressor. d. there will be no proteins available capable of digesting lactose.
Answers
As a bacterium has a faulty lac operon in which there is a structural defect in the operator in this bacterium as there is a structural problem with a segment of DNA that binds a repressor. The correct option is c.
What is a lac operon?A bacterium has a fully lac operon with a structural flaw in the operator. A segment of DNA that binds a repressor in this bacterium has a structural flaw.
The operator in the lac operon is the segment of DNA that binds to the repressor.
In the absence of functional repressor/operator binding, the cell will produce the proteins required for lactose metabolism constitutively.
Thus, the correct option is c.
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The most striking property of the noble gases is their inactivity.
True
False
Answers
Answer:
True
Explanation:
The most significant property of the noble gases (group 18) is their inactivity. They occur in low concentrations in the atmosphere . They find uses as inert atmospheres, neon signs, and as coolants. The three heaviest noble gases react with fluorine to form fluorides.
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genin gm, kent a, birman v, et al. 2009. functional grading of mineral and collagen in the attachment of tendon to bone. biophys j 97:976–985.
Answers
Due to the potential for high levels of localized stress to form at their interfaces, the attachment of different materials presents a significant difficulty.
At one of nature's most severe interfaces, when a tendon attaches to a bone, a stiff, structural "hard tissue," an efficient biologic solution to this challenge can be found. Objective was to create biomechanical models that would explain how the mechanical characteristics of the tendon-to-bone insertion are derived.We looked at the tendon-to-bone insertion and discovered two elements that grade the tendon-to-bone transition mechanically uniquely:
1) a gradation in collagen fiber orientation, as determined by polarized light microscopy, and
2) a gradation in mineral concentration, as determined by Raman spectroscopy.
What is Collagen ?Collagen serves as the main structural protein in the extracellular matrix that makes up the body's numerous connective tissues.It makes up between 25% and 35% of the protein in a mammal's entire body and is the basic building block of connective tissue.Products containing collagen are marketed as having the ability to increase skin blood flow, improve skin elasticity, and minimize visible wrinkles. Our skin doesn't sag because of collagen, which gives us a plump, youthful appearance.To know more about Collagen Fiber please click here : https://brainly.com/question/24244925
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Your question seems incomplete, please refer below for the complete question:
Discuss biomechanical models that detail how the mechanical characteristics of the tendon-to-bone insertion are derived.
humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose.
Answers
The given statement is true.
Humans can digest starch but no longer cellulose due to the fact humans have enzymes that can hydrolyze the alpha-glycosidic linkages of starch but not the beta-glycosidic linkages of cellulose. The enzyme amylase can spoil glycosidic linkages between glucose monomers only if the monomers are linked with the aid of the alpha form.
Enzymes are proteins that assist velocity up chemical reactions in our bodies. Enzymes are imperative for digestion, liver feature and tons more. Too a lot or too little of a positive enzyme can cause health problems. Enzymes in our blood can additionally help healthcare companies test for accidents and diseases.
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Cell membranes allow some molecules to move freely across the membrane, while other molecules are restricted. Which term best describes this capability of a cell membrane?.
Answers
Which table correctly identifies how the plasma membrane contributes to the maintenance of cellular homeostasis?
Answers
The table that correctly identifies how the plasma membrane contributes to the maintenance of cellular homeostasis is Table A.
What is the plasma membrane?The plasma membrane is a structure which surrounds the cell and its function is to separate the interior of the cell from the extracellular environment, thus maintaining the homeostasis of the cell since it will control what enters and leaves this cell.
This structure will be found in all eukaryotic and prokaryotic cells.
Therefore, we can confirm that the table that correctly identifies how the plasma membrane contributes to the maintenance of cellular homeostasis is Table A.
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the process by which the information in a gene directs the synthesis of a protein is called . question 6 options: replication post translation modification gene expression cloning
Answers
The process by which the information in a gene directs the synthesis of a protein is called translation. The correct option is B.
What is translation?Translation is the process by which mRNA directs protein synthesis with the help of tRNA.
The ribosome is a massive complex made up of RNA and protein molecules. Each three-base stretch of mRNA (triplet) is referred to as a codon, and each codon contains information for a single amino acid.
The process of copying genetic information encoded in DNA onto an mRNA strand that directs protein synthesis.
The process of determining the amino acid sequence of a protein by reading the mRNA nucleotide sequence.
Thus, the correct option is B.
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which portion of the cerebal cortext lies directly behind the forehead and is involved in speaking, muscle movements and making plans
Answers
Frontal lobe of the cerebral cortex lies directly behind the forehead and is involved in speaking, muscle movements and making plans.
Frontal Lobe- The frontal lobes of the human brain are the largest and most often affected by traumatic brain injury. Expressive language, voluntary movement, and higher level executive functions are all tightly regulated by the frontal lobes.
Cerebral Cortex- Language and information processing are two sophisticated brain operations that require the cerebral cortex. The frontal, parietal, temporal, and occipital lobes make up the four lobes that make up the cerebral cortex. The cerebrum's main job is to regulate the body's voluntary muscular motions.
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chloroplasts are proposed to have arisen after archaea cells engulfed , in endosymbiosis, allowing the engulfed cell to remain, with specialized function.
Answers
Chloroplasts are proposed to have arisen after archaea cells engulfed Photosynthetic bacteria in endosymbiosis, allowing the engulfed cell to remain, with specialized function.
What is a bacteria?
Prokaryotes are microscopic living things that lack an organelle and a clearly defined nuclear membrane. One variety of prokaryote is bacteria. They can be found everywhere and are essential to both human health and sickness.
According to endosymbiotic theory, a big tiny Archaean organism absorbed a photosynthesis-capable microscopic living organism. It turned out to be a photosynthetic bacteria. The photosynthetic creature thrived inside the larger cell in a mutually beneficial connection rather than being digested. This little photosynthetic creature evolved into the chloroplast, an organelle.
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When an ecosystem contains many different species, there are usually a high number of links in its food web. How does this affect the sustainability of the ecosystem?.
Answers
Answer:
Lets say that one link was removed from the food web, that would make that ecosystem no longer exist.
Hope this helps
The lionfish is a venomous type of fish that is native to the Indo-Pacific and Red Sea but was introduced into the Western Atlantic Ocean. They are predators that eat any other type of fish or invertebrate that fits in its mouth, and reproduce faster than the fish native to this area. What kind of negative impact does the lionfish have on native fish species?
A. Competition for finding a mate decreases, making it easier for other native fish species to reproduce.
B. Competition for survival decreases, making it easier for both lion fish species and native fish species to survive.
C. Competition for food increases, leaving less available food for other native fish species to eat.
D. Competition for spreading disease increases, leaving fewer lionfish available to reproduce.
Answers
Answer:
C
Explanation:
a species like this is typically called invasive, where they can harm the ecosystem from total domination of many layers of the food chain. because the lionfish eats so much, there will be loss food for other species to consume, causing some to die of starvation
Answer:
C
Explanation:
According to Darwin's Theory of Evolutionall of the following are required for evolution by natural selection EXCEPT
A) differential survival and reproduction
B) strength and fighting skills
C)competition for resources
D)variation in the population
Answers
What is natural selection?
Natural selection is a process in which one species is naturally at a higher advantage to survive and reproduce than another. Strength and fighting skills, competition for resources, and variation in the population are all required factors for evolution by natural selection.
Final answer: Option A.) “differential survival and reproduction” is not required for evolution by natural selection.
Answer:
differential survival and reproductionExplanation:
According to Darwin's Theory of Evolutionall of the following are required for evolution by natural selection EXCEPT differential survival and reproduction .
Thesis & Outline
Where and how does the Big Bang Theory not match creation as told in the Bible.
Answers
The big bang does not recognize a supreme being as a first cause as does the bible.
What is the big bang?In accordance with the big bang theory the earth was started at a point and then the universe began to move outwards and expand until the earth got to what it is today. This exclude the possibility of an external force or an external hand that may have played a role in the formation of the earth.
On the other hand, the creationist account has it that God made the heavens and the earth. Thus the earth was fashioned by God as it is in its present form.
Thus the big bang does not recognize a supreme being as a first cause as does the bible. This is the point where the big bang differs from bible account.
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a critical event in the death of a cell is caused by group of answer choices disruption of the plasma membrane s permeability barrier an increase in cellular protein content an accumulation of lipofuscin chronic nutrient insufficiency
Answers
A critical event in the death of a cell is caused by disruption of the plasma membrane's permeability barrier. The correct option is A.
What is plasma membrane?The plasma membrane, also renowned as the cell membrane, is the membrane found in all cells that differentiates the cell's interior from its surroundings.
Necrosis causes cellular death by disrupting the plasma membrane barrier. The primary cause of hypertrophy is an increase in cellular protein content.
Lipofuscin can accumulate as a result of atrophy. Atrophy occurs when cells shrink and lose their differentiated functions as a result of a variety of normal and harmful factors, such as nutrient deficiency.
Thus, the correct option is A.
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given that the glomerular filtration rate of a substance is 100 mg/min, the secretion rate is 20 mg/min and the reabsorption of this substance is 30 mg/min. what is the excretion rate of this substance from the body in mg/min?
Answers
The excretion rate of the substance from the body is 50 mg/min.
The glomerular filtration rate depends on the secretion rate, reabsorption rate, and excretion rate.
Glomerular filtration rate = Secretion rate + Reabsorption rate + Excretion rate
Glomerular Filteration Rate- The volume of plasma filtered by the glomeruli in a given amount of time is known as glomerular filtration rate (GFR), and it is often calculated by measuring the rate at which a drug is cleared from the plasma. The National Kidney Foundation states that typical findings fall between 90 and 120 mL/min/1.73 m2. GFR levels will be lower in older individuals than usual since GFR declines with age.
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When your muscles contract to move your body, such as during walking, work is done, and work requires energy. Based on the law of conservation of energy, from where does this energy come?.
Answers
When your muscles contract to move your body, such as during walking, work is done, and work requires energy. Based on the law of conservation of energy, this energy comes from chemical energy
In order words, the energy which comes from movement of body parts due to contraction of muscles during walking or even jumping is chemical energy
What is energy?Energy can simply be defined as the capacity of doing work. However, there are different forms of energy; among which include the following
Potential energyKinetic energyMechanical energySolar energyChemical energySo therefore, when your muscles contract to move your body, such as during walking, work is done, and work requires energy. Based on the law of conservation of energy, this energy comes from chemical energy
Complete question:
When your muscles contract to move
your body, such as during walking, work is done, and work requires energy. Based on the Law of Conservation of Energy, from where does this energy come?
New energy is created by our cells whenever we need it.
heat
a. mechanical energy stored in ATP
b. chemical energy
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Writing has existed for 5,400 years. Modern humans have a great capacity to read, but 5,400 years is not enough time for humans to have evolved this ability. Therefore, the capacity to read was already natural to homo sapiens. True or false?.
Answers
It is a true statement that the capacity to read was already natural to homo sapiens.
What is evolution?The term evolution has to do with the changes that occur in an organism. We know that from the evolution theory, an organism tends to pass through many stages before it gets to the present stage that it is in the now.
We are told in the question that Writing has existed for 5,400 years. We know that the evolution of the modern man has taken so many million years to ago and that the process of evolution is still ongoing today. The modern man is called Homo Sapiens. Modern humans have a great capacity to read, but 5,400 years is not enough time for humans to have evolved this ability.
It is therefore a true statement from the foregoing that the capacity to read was already natural to homo sapiens.
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Dust from agricultural processes
and construction constitutes
WHAT type of air pollution?
A. Suspended Particulate Matter
B. Ozone
C. Nitrogen Oxides
D. Carbon
Answers
Answer:
A. Suspended Particulate Matter
During glycolysis, one molecule of is broken down into two molecules of pyruvate, driving the synthesis of atp. True or false?.
Answers
This statement is true. During glycolysis, one molecule is broken down into two molecules of pyruvate, driving the synthesis of ATP.
Glycolysis occurs in both aerobic and anaerobic organisms and it splits one molecule of glucose into two pyruvate molecules.
The formula of this process is: Glucose + 2 NAD+ + 2 ADP + 2 Pi --> 2 Pyruvate + 2 NADH + 2 H+ + 2 ATP + 2 H2O
The hydroxyl groups enable phosphorylation. Also, the particular form of glucose used in glycolysis is glucose 6-phosphate.
during the process,1,3 bisphosphoglycerate converts into 3- phosphoglycerate
The released phosphate produces 1 molecule of ATP.
In the next step, phosphoenolpyruvate converts into pyruvate and yields the second molecule of ATP.
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Scientists who study
ocean temperatures
have seen
A. that the ocean is recently becoming colder
B. that the ocean is recently becoming warmer
C. that the ocean temperatures are not changing at all
000
Cpyright ©2003-20aa International Academy of Science. All Rights Reserved.
Answers
2 The diagram below shows the reaction between iron oxide and carbon that produces iron and carbon dioxide. The reaction takes place in a closed system. What is true about the carbon atoms in the reaction? A. The mass of the carbon atoms increases between the reactants and the products of the reaction. B. The total mass of the carbon atoms is the same as the total mass of the oxygen atoms. C. The mass of carbon atoms in the reactants is the same as the mass of carbon atoms in the products. D. The total mass of the carbon atoms is the same as the total mass of the iron atoms.
Answers
The correct answer is C. The mass of carbon atoms in the reactants is the same as the mass of carbon atoms in the products.
Iron is present in the iron ore hematite in the form of iron(ii) oxide. Iron must be extracted by removing the oxygen that caused it to be left behind. Through the reduction reaction, the oxygen is eliminated.The displacement reaction happens because carbon is more reactive than iron. The iron is replaced by the carbon.Reaction = 2Fe₂O₃(s) + 3C(s) → 4Fe(l) + 3CO₂(g)Iron is reduced because its oxidation state is lowered and it turns into neutral iron, whereas carbon is oxidized because its oxidation state is raised.We can see that each atom's number is the same on both sides of the equation. The answer to the provided question is B since there are three carbon atoms on the reactant side and three more on the product side. that is,The amount of carbon atoms in the reactant and product are equal in mass.Therefore, option C. is correct.
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whole-exome sequencing reveals a novel mutation of flna gene in an iranian family with nonsyndromic tetralogy of fallot
Answers
Objective: Tetralogy of Fallot (TOF) is one of the most common congenital abnormalities that want early intervention. Here, for the first time, we file a nonsyndromic form of TOF triggered with the aid of a novel variant in the FLNA gene in two siblings of an Iranian family.
Methods: The family underwent a whole workup, including karyotyping, sequencing of 6 common genes in congenital heart diseases (GATA4, NKX2-5, ZIC3, FOXH1, NODAL, and GJA1), array comparative genomic hybridization, multiplex ligation-dependent probe amplification, and whole-exome sequencing. Segregation and in silico analysis were also conducted for the identified variant.
Results: A variant, c.3415C>T, in the FLNA gene was determined in both affected brothers in this family; this variant used to be heterozygous in their mother. Bioinformatics tools anticipated the variant as a pathogenic one.
Conclusion: Many allelic issues have been said for FLNA mutations. Mutations in this gene may additionally reason a nonsyndromic congenital form of TOF.
The Principle of Segregation describes how pairs of gene variants are separated into reproductive cells. The segregation of gene variants, referred to as alleles, and their corresponding characteristics used to be first located with the aid of Gregor Mendel in 1865. Mendel was once studying genetics by performing mating crosses in pea plants.
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° F= 418, °C and K?
Answers
Answer:
Celsius- 214.44 degrees
Kelvin- 487.594K
Explanation:
kelvin- (° F 418 -32) x 5/9 +273.15= 487.594K
Celsius- (° F 418- 32)x 5/9 - 214.444 C
the many different disciplines that are used to study environmental science include biology, chemistry, economics, and political science.
Answers
The above statement 'the many different disciplines that are used to study environmental science include biology, chemistry, economics, and political science is true.
The field of environmental sciences is an interdisciplinary one as it relates to various other sciences.
In the field of environmental studies, the main area of focus study is the environment, environmental concerns, and its solution. As an environment is influenced by living as well as nonliving things hence biology and chemistry integrate into this science. Also, as the environment of a country plays an important role in economics hence the fields of environmental studies and economics are also related to each other. Political studies is also an aspect of environmental studies because the politics of a country can manage or disrupt a particular environment.
Environmental studies focus on how human beings interpret the environment and they are influencing the environment.
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