People with dark brown eyes have greater amounts of the protein melanin in their irises than people with light blue eyes. The amount of melanin produced is a direct result of _________.
Select one:

Environmental conditions

Their personality

The foods they received as children

DNA

Answers

Answer 1
DNA??? I’m not sure but I’m saying DNA hope I helped!

Related Questions

What is the primary difference between acute illness and chronic illness?

Answers

Acute illness is a sudden onset and chronic illnesses last usually six months or longer.

You see someone on the ground in the parking lot, who appears to be unconscious. after checking the scene for safety, what should you do next?

Answers

You would want to approach the person and see if they are breathing and call for an ambulance.

The process of making nitrogen in the air usable to the plant is called nitrogen _______.

Answers

The answer to that question is Peroxide.

Which nursing diagnosis is most appropriate for a patient experiencing myelosuppression secondary to chemotherapy for cancer treatment?

Answers

There are choices for this question namely:

A) Acute pain
B) Hypothermia
C) Powerlessness
D) Risk for infection

The correct answer is "risk for infection". Chemotherapy not only targets cancerous or tumor cells but also healthy cells. Myelosuppression is the term used to described the suppression of the cells in the myeloid lineage. These cells include the white blood cells (neutrophils, eosinophils, and basophils). In the event of suppression, there will be immune compromise leading to increased risk for infection.

Information gathered from observing the growth of a fish over a month is called Question 2 options: hypotheses. data. variables. inferences.

Answers

Data is the answer because it is information that you got from watching the fish.

Most species of cyanobacteria are enclosed in a _____.

carotenoid pigment
phycoerythrin
mucilaginous sheath
nuclear membrane

Answers

Answer: mucilaginous sheath

Explanation:

These algae are known as "blue algae" because of their pigmentation or "cyanobacteria" because they are prokaryotes. Microbiologists classify cyanobacteria in the realm of Eubacteria. They are the only prokaryote algae. The cellular organization is prokaryotic, without nuclei or organelles. Respiration takes place at the level of plasmalemma and thylakoids. In the center (nucleoplasm), cells contain their genome and circular plasmids. Cyanobacteria often also have a mucilaginous sheath common to many trichomes.

These organisms contain several carotenoid pigments, particularly myxoxanthophyll, which does not occur in any other algae group. Some cyanobacteria are strictly phototrophic, others are optional: they are phototrophic when in the presence of light, but may grow in obscurity using an organic carbon source. Others can use a source of organic carbon as well as inorganic carbon, but only in the presence of light.

During intense exercise, can a muscle cell use fat as a concentrated source of chemical energy? explain.

Answers

Yes, during intense exercise, muscles cell may use fat as a concentrated source of chemical energy. When oxygen is present, the fatty acid chains containing most of the energy of a fat are oxidized and fed into the citric acid cycle and the electron transport chain. Nonetheless, during intense exercise, oxygen is scarce in muscle cells, so ATP must be generated by glycolysis alone. 

During intense exercise, muscle cells primarily use carbohydrates due to their rapid conversion to ATP, whereas fat metabolism is slower.

During intense exercise, muscle cells primarily rely on carbohydrates, specifically glucose, as the main source of energy. This is because glucose can be rapidly metabolized through glycolysis to produce ATP (adenosine triphosphate), which is the immediate energy currency of cells. Glycolysis doesn't require oxygen and can generate ATP quickly to meet the high energy demands of intense exercise.

On the other hand, fat metabolism, which involves the breakdown of fatty acids, is not as efficient for providing energy during intense exercise. The breakdown of fats requires more oxygen and is a slower process compared to glycolysis. Additionally, fatty acids cannot be metabolized as quickly as glucose, making them less suitable for meeting the immediate energy needs of intense activity.

However, this doesn't mean that muscle cells can't use fat as a source of energy during intense exercise at all. In fact, during prolonged or endurance exercise, when glycogen (the stored form of glucose) becomes depleted, muscle cells can start to rely more on fat metabolism to sustain energy production. As exercise intensity decreases or becomes more prolonged, the body shifts towards utilizing more fat for energy, as fatty acids can provide a more sustained source of ATP production when oxygen is readily available.

So, while muscle cells can use fat as a source of energy, especially during lower intensity or prolonged exercise, during intense exercise, they primarily rely on carbohydrates due to their ability to produce ATP rapidly through glycolysis.

The amphibians, reptiles, and mammals comprise which group?

Answers

I believe they comprise  a group called tetrapods . Tetrapod are organisms whose evolution began about 400 million years ago in the Devonian period with the earliest tetrapods evolving from lobe-finned fishes. They are categorized as a biological super class Tetrapoda. which includes all living things and extinct amphibians, reptiles, birds and mammals.

Some fungal species live in plants and can kill herbivores that feed on the plant. what type of relationship does this fungus have with its host?

Answers

I believe it is a mutualistic relationship. Mutualism is an association or relationship between two organisms of different species in which each organisms benefits. For example in this case the plants provides a shelter for the fungal species while the fungal species kills the herbivores who feed  and destroy the plant.
Final answer:

The relationship between the fungus and its host plant, where the fungus can kill herbivores that feed on the plant, is a mutualistic relationship. The fungus provides protection for the plant, while the plant provides nutrients for the fungus.

Explanation:

The relationship between a fungus and its host plant, where the fungus lives in the plant and kills herbivores that feed on the plant, is a mutualistic relationship. This is because both the fungus and the plant benefit from the interaction. The fungus provides protection for the plant by repelling herbivores, and the plant provides nutrients and a place to live for the fungus.

Other examples of fungal-plant mutualism include endophytes, which live inside plant tissue without damaging the plant. Endophytes release toxins that repel herbivores and confer resistance to environmental stress factors.

Learn more about mutualistic relationship here:

https://brainly.com/question/31679783

#SPJ12

An individual afflicted with Lupus, a disorder occurring when the body’s immune system attacks its own tissues and organs, suffers from symptoms including fatigue, chest pain, and joint stiffness and swelling. Of the types of proteins listed below, which is most likely responsible for the onset of this disorder?

A. Storage proteins.

B. Transport proteins.

C. Signaling proteins.

D. Defense proteins.

Answers

The answer is D) Defense proteins

Answer:

D) Defense Proteins

Explanation:

I got this question right.

An nrbc (nucleated red blood cell) is _______ a mature erythrocyte.
a. less mature than
b. the same as
c. more mature than
d. from a different cell line than

Answers

Answer: A. 


Nucleated red blood cell is less mature than a mature erythrocyte. They are erythroid precursors that have apoptotic nucleus, the last nucleated stage of red blood cell production to contain a defined, intact nucleus before the erythrocyte losses its nucleus.

Moreover, they are confined to the bone marrow, in the peripheral blood in newborns and in uncompensated hemolytic anemia.

Units of volume can be ml or cm3. which unit would normally apply to irregularly-shaped solods

Answers

cm3 unless its luiquid right
? hope this helps

What is considered to be the average natural mutation rate that occurs during dna replication? what is considered to be the average natural mutation rate that occurs during dna replication? one in every trillion nucleotides replicated. one in every ten thousand nucleotides replicated. one in every billion nucleotides replicated. one in every million nucleotides replicated?

Answers

C. One in every billion nucleotides replicated

what is the difference between transcription and translation

Answers

Transcription is the synthesis RNA from a DNA template where the code in the DNA is converted into a complementary RNA code. Translation is the synthesis of a protein from an MRNA template where the code in the mRNA is converted into an amino acid sequence in a protein.
Final answer:

Transcription and translation are two fundamental processes in protein synthesis. They differ in location, molecules involved, and process.

Explanation:

Transcription and translation are two fundamental processes in protein synthesis. Transcription is the process where DNA is used as a template to produce mRNA in the nucleus. Translation, on the other hand, occurs in the cytoplasm and involves the synthesis of protein using the mRNA as a template.

There are several differences between transcription and translation:

Location: Transcription occurs in the nucleus, while translation occurs in the cytoplasm.Molecules involved: Transcription involves the conversion of DNA to mRNA, while translation involves the conversion of mRNA to protein.Process: Transcription involves the copying of a specific gene sequence from DNA to RNA, while translation involves decoding the genetic information in mRNA to determine the sequence of amino acids in a protein.


Could you please check my work??
Adaptations may occur when...
MARINE SCIENCE

1.) Adaptations may occur when...
a.) an individual needs to survive a dangerous situation.
b.) an individual wants to attract a mate
c.) a species wants to move to a new environment
D.) a trait is advantageous and is passed through generations ( MY ANSWER)

2.) What role does INTRASPECIES competition play in natural selection?
a.) there is competition within a species for resources, and only some individuals will survive.
B.) there is competition within a species for resources, and only the single most fit individual will survive (MY ANSWER)
c.) there is competition between species for resources, and only one species will survive
d.) there is competition between species for resources, and only one individual per species will survive.
(I KNOW IT MUST BE EITHER (a) or (b)

3.) Look at the body shape of the picture shown below...

PICTURE WILL BE PROVIDED
Which one is best adapted to live in open water in epipelagic zone, and why?
a.) Fish A because of its elongated body and powerful tail.
b.) Fish B because of its flattened shape and eyes on the dorsal side.
C.) Fish C because of its streamlined shape and lack of pectoral fins (MY ANSWER : C because it's the darkest
Color and it just looks like the kind of fish that would be in that zone)
d.) none of these because they are sedentary

4.)Which of the following is an example of an inherited variation?
a.) An injury that results in a scar
B.)An eye color different from one's parent (MY ANSWER because it's an inherited trait the offspring could get from ancestors)
c.) A change in muscle mass due to excercise
d.) A variation in speed due to practice

Which of the following graphic organizers best compares natural selection and artificial selection
PICTURE WILL BE PROVIDED
MY ANWER : A because the others labeled below natural selection and artificial selection are wrong with the definition I'm not sure if the similarity is the same compared to D

7.) how does an environmental factor such as overfishing affect genetic factors in population?
a.) overfishing will lead to increased genetic variation.
b.) Environmental factors do no affect genetics factors
C.) Genetic traits that help fish survive are more likely to be seen in future generations. (MY ANSWER)
d.) Genetic traits that are targeted by the fishing industry are more likely to be seen in future generations

7.) Which of the following would be considered a benefit in over production?
A.) The exponential growth of a population ( MY ANSWER)
b.) the survival of the fittest due to competition of resources
c.) the exchange of genetic material between populations
d.) the change in an ecosystem due to the increased population

Answers

Answer 1:

The correct answer is D.

D.) a trait is advantageous and is passed through generations

There are different kind of adaptations occur in the life of organisms. Adaptations actually help organism to blend with their environment and are necessary for the survival of an organism. When organisms found a trait useful for them, they adopt it and with the passage of time they inherit that trait to their off springs.

Answer 2:

The correct answer is B.

B.) there is competition within a species for resources, and only the single most fit individual will survive

Intraspecies competition means the competition within the individual of same species and only the fittest of all the individual will survive. This is the phenomenon of natural selection, in which nature select only most  fit individual for the next generations.

Answer 3:

The correct answer is C.

C.) Fish C because of its streamlined shape and lack of pectoral fins.

Epipelagic zone is the zone of the sea where most of the sunlight penetrate. It is also called sunlight zone. Fish C is best adopted here because of its streamline shape and lack of pectoral fins.

Answer 4:

The correct answer is B.

B.)An eye color different from one's parent

The inherited traits are the traits of individuals that are inherited from parents through genes. So, if an individual exhibit different eye color from his parents. It meas that he is showing inherited variation.

Answer 5:

The correct answer is "A" according to graphic organizer.

Genetics always include both natural and artificial factor so that they can examine both the natural and artificial factor in inheritance or heritable variation.

Answer 6:

The correct answer is C.

C.) Genetic traits that help fish survive are more likely to be seen in future generations.

The environmental factor such a over fishing affect genetic factors such as that only that genetic traits that help fish survive are more likely to be seen in future generations.

Answer 7:

The correct answer is B.

b.) the survival of the fittest due to competition of resources.

In the over production of a population, the survival of the fittest due to competition of resources is a benefit. Because in this way only some of the fittest individual will survive and it will reduce the over production.

Why are steroids important to life?

Answers

Steroids are naturally occurring as sterols, adrenal, sex hormones, some vitamins and make up most drugs as synthetic steroids.

Types Of Steroids and Their Functions
1. Anabolic Steroids
-increase muscle mass
-promote cell growth and division
-testosterone( natural anabolic steroid) is used in sperm production, development of male reproductive organs and emergence of male secondary sexual characteristics.
-stimulates bone and muscle growth.

2. Sex Hormones
-produced by adrenal cortex
-aid in development of gametes
-prepare females for pregnancy, menstruation

OTHER
-enable longer athletic sessions
-increase protein synthesis
-Anti-inflammatory steroids can reduce swelling, pain and other manifestations of inflammation

the process by which one large nucleus splits into two nuclei

Answers

The name of this process is: Nuclear Fission
Nuclear Fission is considered as transmutation since the Resulting fragments after the split is not the same element as the initial atom.
This process also would result in large amount of energy from the production of Gamma Photons and neutrons.

Gender, the sense of being male or female, is well-established by the time children are

Answers

Gender, the sense of being male or female is well established by the time children are in pre-school at the age of 3-5 years. This is the age where children are usually eager to learn. They always want to touch, taste, smell see and test things for themselves. This is where they will notice differences in behavior and characteristics of people. That is why they will start to identify different genders around them.

Which are structures of the excretory system? Check all that apply. kidney spleen bladder esophagus ureter urethra

Answers

The organs listed above are all part of the excretory system except for the spleen and the esophagus.
The kidneys act to filter our blood, and remove wastes, which eventually pass out of us through urine,
The bladder acts to collect and store urine until it can be emptied through urination.
The ureter runs from the kidneys to the bladder whereas the urethra runs from the bladder to exit the body.

The nurse is assessing a 15-year-old high school student who is worried because she has not yet begun menses. the nurse tells the student that she may attain her menses late. what assessment findings might the nurse have noted about the patient? the patient:

Answers

The assessment findings that the nurse should note in the patient is Anorexia nervosa, thyroid disorders and as well as Type 1 Diabetes mellitus.

 

It is because a female who have a low in regards of her body mass index because of malnutrition can have a delayed onset of menstruation and those with type 1 diabetes or thyroid disorder are known to cause amenorrhea of which is defined as having an absence of menstruation because of interruption in the hypothalamic pituitary ovarian uterine.

The nurse have noted that the patient might have anorexia nervosa due to low body mass index, due to malnutrition a delayed onset of menstruation may result. Anorexia is an eating disorder characterized by low weight and a strong desire to be thin. Another assessment finding is that the patient might have type 1 diabetes mellitus where there is a risk of developing amenorrhea caused by interruption in the hypothalamic-pituitary-ovarian-uterine axis.

 

Ddee pea plants can produce _____ type(s) of gametes, but a ddee plant can produce _____ type(s) of gametes.

Answers

Final answer:

A homozygous ddee pea plant can only produce one type of gamete, while a heterozygous pea plant like Ddee can produce multiple types, depending on the number of gene loci with varied alleles. Pea plants that were studied by Mendel can produce different numbers of gametes based on their genotype.

Explanation:

The student's question pertains to the types of gametes produced by pea plants with different genotypes. A ddee pea plant can produce only one type of gamete because it is homozygous at both gene loci (dd and ee), meaning all gametes produced will carry the alleles d and e. On the other hand, a heterozygous pea plant (like Ddee) can produce multiple types of gametes depending on the number of gene loci with varied alleles. For example, if there are two heterozygous gene loci, say DdEe, it can produce four different types of gametes (DE, De, dE, and de).

In Mendel's genetic inheritance studies, pea plants were diploid and had 14 chromosomes. Without crossing over, the number of unique gametes one pea plant can produce depends on the number of heterozygous gene loci. The YyRr plant, which produces four different gametes, we can infer that for each heterozygous gene locus, the number of possible gametes doubles. Therefore, a pea plant with one heterozygous pair will produce two types of gametes, and for two heterozygous pairs, as in YyRr, it will produce four types of gametes (YR, Yr, yR, yr).

Sac-like structures under the plasma membrane are a characteristic of which major group of protists?

Answers

The answer is alveolates. The sac-like structures under their plasma membrane are called alveoli. The alveoli provide support to the plasma membrane. Examples of groups of alveolates are ciliates, such as Paramecium, dinoflagellates, apicomplexa, and foraminifera. They lie under the phylum, Ciliophora.

The two major veins joining into the superior vena cava are the

Answers

The brachiocephalic (left and right ones). Hope this helps! ( *’ω’* )

What process is most important in the expansion of plant cells?

Answers

Water uptake, water is 90% of the plant cells expansion

Dramatic changes in sea level occurred throughout the Cenozoic era and the rise and fall of sea level is recorded in the rocks of the _______________. Amazing numbers of fossil clams, snails, and sand dollars can be found in these marine rocks, along with fossilized whale bones and shark teeth.

Answers

Answer:

C

Explanation:

Dramatic changes in sea level occurred throughout the Cenozoic era and the rise and fall of sea level is recorded in the rocks of the Coastal Plain. This makes sense as it is the geographic region closest to the Atlantic Ocean.

Answer:

The answer is C

Explanation:

After protein translation is complete, the newly-formed polypeptide A. embeds itself on the surface of a ribosome, which carries it back to the nucleus for alterations. B. folds into a three-dimensional structure due to the interaction of neighboring amino acids in sequence. C. moves to the mitochondrion, where it is broken down to form ATP. D. breaks down the RNA molecules that helped form the polypeptide.

Answers

B. folds into a three-dimensional structure due to the interaction of neighboring amino acids in sequence

Answer:

B. folds into a three-dimensional structure due to the interaction of neighboring amino acids in sequence.

Explanation:

After completion of translation the nascent polypeptide molecule enters endoplasmic reticulum (ER) from cytosol in order to fold into a specific three dimensional structure. A polypeptide becomes functional only after being folded, in nascent form it is non functional. In ER, a linear polypeptide molecule folds to form either an alpha helix or a beta sheet due to hydrogen bonding between various amino acids, these are secondary structures. These secondary structures then fold even more to form tertiary structure with the help of ionic bonds, hydrophobic interactions and disulphide linkage/bonds between various amino acids. After tertiary structure, finally a quaternary structure is obtained because of oligomerisation of two or more tertiary proteins. This well folded and oligomerised protein is usually a functional form of protein.

If a forest is producing enough oxygen for both the plants and the animals in the forest to use, is there more photosynthesis happening or more respiration happening within plants?

Answers

Plants and animals are interdependent on each other plants produce oxygen by photosynthesis and animal produce co2 by cellular respiration this CO₂ utilize by plants, hence photo photosynthesis and respiration both are happening in equal amounts.

What is the relation between photosynthesis and respiration?

Carbon dioxide is exhaled and oxygen is breathed by animals. Plants absorb carbon dioxide and expel oxygen into the atmosphere. Animals breathe in oxygen and exhale carbon dioxide during the respiration process.

In contrast, plants use this carbon dioxide gas to make food and release oxygen into the atmosphere through the process of photosynthesis. Thus, we may conclude that animals and plants cooperate to exchange gases in the atmosphere.

The process by which leaves take in carbon dioxide and water and use the power of the sun to transform them into chemical compounds like sugars that nourish the tree is known as photosynthesis.

Therefore photosynthesis produces oxygen and respiration produces CO₂, hence both processes happen in equal amounts.

Learn more about photosynthesis, here:

https://brainly.com/question/1388366

#SPJ2

The role of inflammation in the etiology of atherosclerosis has emerged over the last few years. which lab test is a marker for systemic inflammation?

Answers

The correct answer is C-reactive protein or CRP.

CRP is one of the most important marker for systemic inflammation. Another equally important marker for systemic inflammation is the erythrocyte sedimentation rate or the ESR. CRP and ESR are acute phase reactants that are synthesized in the liver by hepatocytes in response to proinflammatory cytokines (i.e. IL-2, TNF, IL-6). 

Complete this vocabulary exercise relating to enzymes. match the words in the left-hand column to the appropriate blank in the sentences in the right-hand column. view available hint(s)

Answers

1. Competitive inhibitors compete physically and structurally with the substrate for an enzyme's active site, they can be out competed by adding extra substrate. The inhibitor will have the same binding site configuration as the substrate thus meaning the enzyme will accept it. An example of competitive inhibition could be malonic acid which competes with succinate for active sites of succinic dehydrogenase, an important enzyme in the krebs cycle.

2. Non competitive inhibitors do not compete for the active site, but inhibit the enzyme by binding else where and changing the shape of the enzyme. Am example of non competitive inhibition could be cyanide which combines dehydrogenase with the cytochrome enzymes responsible for the transfer of hydrogen atoms during cellular respiration. This shows that the substrate in the active site of the enzyme.

3. Irreversible inhibitors bind directly to the active site by covalent bonds, which change the structure of the enzyme and inactivate the enzyme permanently. Most medications are enzyme inhibitors of one kind or another.

Which of the following contributes to global warming?

A) acid rain
B) greenhouse gases
C) tropospheric ozone
D) ozone hole

Answers

Answer: B) greenhouse gases

Greenhouse gases form a wrap around the Earth that passes heat to penetrate to the surface but not to return to the universe. Greenhouse gases are water vapor (H2O), carbon dioxide (CO2), methane (CH4), CFC · HCF · PHC (also F gases, fluorinated hydrocarbons), nitrous oxide (N2O) and sulfur hexafluoride (SF6). 
The greenhouse effect is the term for heating the planet Earth caused by a disturbance of the energy balance between the amount of radiation that receives from the Sun and radiates the Earth's surface into space. This effect is the result of an increase in the amount of radiation that cannot be emitted into the universe from the surface of the Earth, but it absorbs the atmosphere and becomes warmer.
Other Questions
Which of the following statements about the subarctic climate region is false? A. The subarctic climate region has extreme annual climate changes. B. The subarctic climate region has short, mild summers and long, cold winters. C. The majority of the ground in a subarctic climate region is covered in permafrost. D. The majority of the precipitation in a subarctic climate region is in the form of snow. the distance around a circle (the circumference) is about 3.14 times the diameter. If a circulares table has a diameter of 3 feet What is the circumference can somebody please help me I'm stuck xD Find the area of circle B in terms of . What was happening in America on the home-front as the War dragged on? In 1865, jules verne proposed sending men to the moon by firing a space capsule from a 220-m-long cannon with final speed of 10.97 km/s. what would have been the unrealistically large acceleration experienced by the space travelers during their launch? (a human can stand an acceleration of 15g for a short time.) How can imagery be used in a speech ? A. to organize ideas B. to inspire the audience C. to provide evidence D. to project confidence Jen has 12 ounces milkshake. 4 ounces in the milkshake are vanilla, and the rest is chocolate. What are two equivalent fractions that represent the fractions of the milkshake that is vanilla? Yo hablo espaol. correct incorrect The difference between two numbers is 66. The sum of the two numbers is 88. Find the greatest number What does the first stanza of"Some Keep the Sabbath Going to Church"suggest about the speakers view of religious customs?She does not believe in creating religious customs.She participates in religious customs in an unconventional way.She finds religious customs to be tedious.She participates only in religious customs that relate to nature. Does the interest rate increase at a constant rate? 6 months = 2.4% 9 months = 2.9%12 months = 3.0%18 months = 3.1% What resolution to the problem does Gandhi offer, encouraging his fellow Indians to do the same? A. He demands a rebellion, encouraging his fellow countrymen to fight back against their oppression. B. Gandhi wants to remain in alliance with Britain, and encourages his fellow countrymen to remain loyal to the crown also. C. He does not harbor hatred for anyone, encouraging his countrymen to do the same. D. Gandhi is angry with Britain, and encourages his fellow countrymen to feel this same anger. Find the general solution to y+7y=0y+7y=0. give your answer as y=.. A reaction occurs when solid X is placed into solution Y. As a result, the temperature of the new solution increases by 3C. The temperature rises another 2C when more of solid X is added to the solution. What does this indicate about the effect of adding more solid? It increased the number of molecular collisions. It decreased the number of molecular collisions. It decreased the space between the molecules and lowered the reaction rate. It increased the space between the molecules and increased the reaction rate What are chemicals that transfer impulses from one neuron to another called? WILL GIVE A BRAINLEST !!!!The graph of a logarithmic function is shown below.What is the domain of the function?x < 0x > 0x < 1all real numbers Find the ordered triple of these equations. 2x - 3y - 4z = -21 -4x + 2y - 3z = -14 -3x - 4y + 2z = -10 Unlike almost all ferns, seed plants ________. Algebra 1 (pic included) In ancient times, many people believed in a geocentric model of the solar system, where the Earth was the center of the system. During the 16th and 17th centuries, men such as Copernicus, Kepler, and Galilei theorized or found evidence that the Sun was actually the center of the solar system. However, despite convincing evidence, this idea was not accepted until some time later.Why was this idea not initially accepted? A. After a theory has been around for one hundred years, it cannot be changed. B. There was no evidence published supporting their ideas. C. It is difficult to change a commonly held belief. D. The Sun is not large enough to be at the center of the solar system.