Answer: D I believe
Explanation:
British land snails primarily occur in two extreme phenotypes. This is an example of
a. directional selection.
b. stabilizing selection.
c. disruptive selection.
d. genetic drift.
e. mutation.
British land snails primarily occur in two extreme phenotypes. This is an example of disruptive selection, which means option C is the right answer.
British land snails are the native organisms of north west Europe. They are found in two extreme forms only because disruptive selection favors only extreme phenotypes to sustain in the changing environment, while the intermediate phenotypes are either rejected naturally by the nature or they fall prey to other large animals and so their population is very less in nature particularly their native habitat.
Disruptive selection causes extreme phenotypic population to get more easily adaptive in nature and helps them increase their population through reproduction. Thus extreme population has higher frequency than other variations present.
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Question 22 of 22 Several members of the family in the pedigree who suffered from a disease are colored in black. Currently deceased members of the family are struck out with a line. Based on the data in the pedigree, propose a Mendelian model that would explain the inheritance of this disease. Explain how the data is consistent with your model. A scientist hypothesizes that a mutation at a single locus is responsible for the pattern of inheritance seen in this pedigree. Explain how a mutation in a gene can arise during meiosis. Describe one strategy organisms use to prevent such mutations from arising.
A. Many families have Alzheimer's disease. From this we conclude that the disease is X-linked recessive.
B. Meiosis is the process of generating gamete cells. There are two choices: mutual break join and another non-reciprocal break copy.
Many families are affected by Alzheimer's disease. It cannot be autosomal inherited because it affects more men than women. Affected males in the second generation have many affected children with normal wives.
If it was autosomal dominant, the sick father would have passed it on to all his second-generation children, but that is not the case. Therefore, it cannot be autosomal dominant.
If it had been autosomal recessive, he would not have affected his children, as his wife appears normal. increase. Therefore, it is not an autosomal abnormality.
Not X-linked dominant, in which case the affected father passed his only X chromosome to his daughter, making her daughter sick. But in this case, the sons are involved. Therefore, it is not X-linked dominant.
From this we conclude that the disease is X-linked recessive.
B. Meiosis is the process of generating gamete cells. Mutations can occur during meiosis in various ways such as double-strand breaks, inversions and point mutations. Important mutation types include missense, nonsense, and point mutations. Cells use multiple repair mechanisms to repair DNA damage or mutations during meiosis. One of the most efficient mechanisms is double-strand break repair by homologous recombination (HR).
Here, the DNA is unwound at the mutated region by recA loading. Recombination with homologous pairs continues through the RecBCD complex.
Here are his two alternatives: reciprocal break join and another non-reciprocal break copy.
Repair normally occurs during her S phase of the cell cycle, when the cell divides its DNA. However, mutations that occur during meiosis, such as chromatid pairing and recombination, are not easily repaired. Cells stop dividing only when the mutation gets worse.
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The passage describes current research on the implications of histone methylation in plants.
Based on the information in the passage, what testable scientific question could be asked about the influence of chromosome structure on an organism's traits?
A.
How does histone methylation prevent organism growth and cell division during periods of heat stress?
B.
Is histone methylation the best way for plants to increase their expression of heat shock proteins?
C.
Will histone modifications permanently upregulate heat shock protein expression after heat stress exposure?
D.
Can histone modifications that prime a plant to survive heat stress be transmitted from parents to offspring?
Histones include a variety of basic residues that can be methylated, and the results of this methylation depend on the type of basic residue, where it is methylated, and where it is located.
What is Histone Methylation?Specific enzymes have the ability to add or remove methyl marks during the dynamic process of histone methylation. In order to influence phenotypic outcomes, other proteins can identify and bind methylated residues.
By way of DNA sequence, non-coding RNA, DNA methylation, or other post-translational signals on histone tails, histone-modifying enzymes might be attracted to particular loci.
In some cases, histone methylation can be passed down from parents to offspring and can be either dynamic or stable throughout a cell's life, including during mitosis and meiosis.
Therefore, Histones include a variety of basic residues that can be methylated, and the results of this methylation depend on the type of basic residue, where it is methylated, and where it is located.
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Which of the following statements about the distribution of sap throughout a plant is true?
a) The driving force for sugar movement is transpiration.
b) The mechanism that explains the movement of sugars throughout a plant is called the pressure-flow hypothesis.
c) Companion cells form the conducting tissue for sap.
d) The main component of phloem sap is glucose.
The statements that are true about the distribution of sap throughout a plant are:
a) The driving force for sugar movement is transpiration.
b) The mechanism that explains the movement of sugars throughout a plant is called the pressure-flow hypothesis.
c) Companion cells form the conducting tissue for sap.
Transpiration is the process where water is lost from the leaves of the plant and the resulting negative pressure in the leaves pulls water from the roots.
The pressure-flow hypothesis describes how the pressure difference in the leaves and roots is used to drive the movement of sugars through the plant.
Companion cells are specialized cells found in phloem tissue that help to support the sieve tube cells which are responsible for the actual transport of sap.
Phloem sap is a complex mixture of sugars and other substances and not only glucose.
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1. Which organisms are primary producers in this food web? How do you know?
2. Which organisms are primary consumers in this food web? How do you know?
3. Which organisms are apex predators in this food web? How do you know?
4. Are there any omnivores in this food web? How do you know?
Answer:
corals is the primary producers.planktonsharkYou are attempting to synthesize rRNA in a test tube using DNA isolated from mouse cells. In addition to the template DNA, ribonucleotides, and the necessary transcription factors, you should also add what enzyme to the test tube?
poly-A polymerase
RNA polymerase III
RNA polymerase I
RNA polymerase II
In addition to the template DNA, ribonucleotides, and the necessary transcription factors, you should also add RNA polymerase I enzyme to the test tube.
The pace of protein synthesis, which is closely linked to ribosome production and rRNA transcription, directly affects the rate of cell development. Therefore, rRNA synthesis must be synchronised with other protein translational components using intracellular cues. It is known that Myc interacts with human ribosomal DNA to promote the transcription of rRNA by RNA polymerase I. To ensure that rRNA synthesis and Pol I-mediated transcription are properly regulated, two distinct mechanisms have been found. The first phase involves fluctuations in the amount of genes that are being transcribed at any particular time due to the enormous number of rDNA genes that are available for transcription (several hundreds).
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What would happen if a mistake were not caught by the proofreading mechanism and became permanent in the DNA
If a mistake were not caught by the proofreading mechanism and became permanently incorporated into the DNA, the consequences could be catastrophic.
The DNA is the blueprint for all life, and any mutation or alteration can cause a range of problems, from minor to severe. If the mistake were to alter a gene that is important for cell survival, it could lead to a range of health problems, from mild to life-threatening.
For example, if a gene that is responsible for the production of a certain enzyme is altered, it can cause a metabolic disorder, leading to physical and mental disabilities. If the mistake were to alter a gene that is responsible for the functioning of a specific organ, such as the heart or brain, it could lead to serious health problems, such as heart defects or neurological disorders.
If the mistake were to alter a gene responsible for the development of an organism, it could lead to serious developmental defects or even death. For example, if a gene that provides instructions for the development of the body's organs is altered, it could lead to serious malformations or even death.
In addition to the health risks, a mistake in the DNA could also lead to changes in the species. For example, if a mutation alters a gene that is important for the survival of a species, it could lead to the extinction of the species. This could be due to a decrease in fertility, a decrease in the population size, or an inability to adapt to a changing environment.
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Phototropism is a _____ tropism involving _____.
positive; water
positive; sunlight
negative; touch
negative; gravity
Answer:
The third to last.
positive;sunlight
Why did Mendel carry out an experiment to study inheritance of two traits in garden pea?
Mendel carried out experiments to study the inheritance of two traits in garden pea as garden pea are bise-xual, self-pollinating, have a short life span and also have visible phenotypic characters.
Mendel conducted plant-breeding experiments using garden pea. He studied the inheritance of two traits to understand if the inheritance of a particular trait affects the inheritance of another trait.
He chose garden pea for his experiment as they are bise-xual in nature, that is the flowers have both male as well as female reproductive parts and therefore are able to self-pollinate. They also have easily observable physical characters and a short life span which makes them easier to maintain as they grow quickly.
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6. Prepare a dichotomous key for the five fish in Figure 3.
REMEMBER: 1.) Each step has only two options. 2.) The options should be about the same characteristic.
Instead of ending with the family name for these fish, you should end with the numbers I, II, III, IV, and V. To
help you get started, I have given you the first pair of statements.
1.A.
B.
2.A.
Figure 3.
If the fish has a long, tube like body
If the fish does not have a tube like body
IV
******
A dichotomous key is a tool that can be used to identify organisms or objects in the natural world, such as plants, animals, or rocks. The dichotomous key for the given question is as follows in the explanation part.
What is a dichotomous key?A dichotomous key may be characterized as a type of key that is significantly utilized for the identification of organisms based on a series of choices between alternative characters.
If the fish has a long, tube-like body: I and IV. If the fish does not have a tube-like body: II and V. If the fish has a spherical appearance: II and V.If the fish does not have a spherical appearance: I and IV. If the fish swims at a rapid speed: I and IV.If the fish does not swim at a rapid speed: II and V.Fish that possess proper gills: III and IV. Fish that do not possess proper gills: I and V. Fish that absorb more water: I and IV.Fish that do not absorb more water: II and V.Therefore, the dichotomous key for the given question is well described above.
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List all the possible genotypes of the offspring from your Punnett
square in question 4. Next to each genotype write the corresponding
phenotype---short stems or tall stems.
we see that there are three possible genotypes that could result from this crossing: AA, Aa, aa. The genotypes AA and Aa will result in the yellow pea phenotype because A is dominant. Only aa will produce the green pea phenotype.
A Punnett square is a graph that makes it simple to ascertain the anticipated proportion of various genotypes in children of two parents. Figure below illustrates a Punnett square for pea plants. In this instance, flowercolor is heterozygous for both parents (Bb). The top of the graph represents the gametes produced by the male parent, while the sides represent the gametes produced by the female parent. By correctly filling in the Punnett square's cells, we may identify the various possible allele combinations in their progeny (alleles).
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What is the relationship of III-1 to 111-2?
The relation of III-1 to 111-2 is that they are the married couple having some common ancestor and having 3 children where 1 girl and 1 boy suffer from some sex linked recessive disease.
What is Sex linked recessive disease?X-linked recessive inheritance also known as Sex linked recessive disease which is defined as the mode of inheritance in which a mutation in a gene on the X chromosome causes the phenotype to always be expressed in males and in females that are homozygous for the gene mutation. Females with one copy of the mutated gene are carriers.
Examples of X-linked recessive disease are red-green color blindness and hemophilia A where there is red-green color blindness. Red-green color blindness simply means that a person cannot differentiate between red and green colors (usually blue-green).
Thus, the relation of III-1 to 111-2 is that they are the married couple having some common ancestor and having 3 children where 1 girl and 1 boy suffer from some sex linked recessive disease.
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When a person looks at a bright light, tiny muscles in the eye contract so less light can enter the eye. Which are most likely the characteristics of this muscle
At the point when an individual glance at a brilliant light, minuscule muscles in the eye contract so less light can enter the eye. These are in all probability the attributes of this muscle nonstriated, compulsory, and connected to the eyeball.
They are smooth muscles (nonstriated) that are not controlled intentionally. You don't get those minuscule muscles on your own will when you check a brilliant light out. It is additionally connected to the eyeball since it agrees to guarantee the most un-conceivable measure of light gets to your eye.
A few capabilities are automatically performed, for example, breathing, processing, heart pulsating, eye reflexes, and so on, however, a few compulsory activities have intentional control partially - models are breathing, salivation, deglutition (gulping), poop, micturition (pee) and others.
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The efficiency of glycolysis is approximately
A) 0.2%
B) 2%
C) 20%
D)200%
Answer:
The correct answer is B.
Explanation:
One similarity and one difference between hydrolysis and carbonation.
One similarity between hydrolysis and carbonation is that they are both chemical reactions that involve the addition of water to a compound.
One difference between hydrolysis and carbonation is that hydrolysis involves the breakdown of a compound into smaller molecules through the addition of a water molecule, whereas carbonation involves the addition of carbon dioxide to a compound. Hydrolysis is a chemical reaction that occurs when a compound reacts with water, whereas carbonation is a chemical reaction that occurs when a compound reacts with carbon dioxide.
How does Hardin’s example of the herdsman and his mathematical justification (nearly +1 and fraction of -1) embody the tragedy of the commons?
Garrett Hardin used the expression for the first time in a 1968 Science article.
The Tragedy of theere is Commons' core claim is that when something is owned by a collective (rather than a single person), its overall sustainability may suffer since th no single entity that is legally in control of or responsible for it. This argument states that people frequently make decisions that advance their own interests, regardless of how those decisions could affect other people. Garrett James Hardin is an environmental expert from the United States. He wrote an essay with the same title that was published in Science in 1968, and after reading it, he decided to devote the remainder of his life to researching human behaviour.
Any attempt to control nature will result in a variety of consequences, many of which are unexpected. Several websites have referred to Garrett as a white nationalist because of his violently anti-immigrant attitudes, eugenics beliefs, and views on multiethnicity. The Southern Poverty Law Center characterised his writings as "frank in their bigotry and quasi-fascist ethnonationalism."
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Where is ATP made in respiration?
The majority of ATP synthesis takes place within the mitochondrial matrix during cellular respiration, with each molecule of glucose oxidized creating around 32 A T P molecules.
ATP produced in mitochondria serves as the main energy source for vital biological functions such muscle contraction, nerve impulse transmission, and protein synthesis. The majority of the ATP produced during cellular respiration is created in the mitochondrial matrix, where each glucose molecule that is oxidised yields roughly 32 molecules of ATP.
Gradients are produced as a result of protons being pumped out of the matrix as electrons move down the chain and release energy in the process.
Protons flow back into the matrix and are converted into ATP by an enzyme called ATP synthase.
The inner mitochondrial membrane contains ETS.
The majority of the ATP in cells is produced by the enzyme ATP synthase, which does this by converting ADP and phosphate to ATP. ATP synthase is found in the membrane of mitochondria, which are cellular organelles; in plant cells.
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Is Colin's evidence relevant to his claim?
No, Colin's evidence is not relevant to his claim.
Since drone flying is a sport rather than a concern for privacy, Colin's evidence does not support his allegation. Colin gives evidence that is connected to the idea that flying drones is a sport by noting that coordination and technical abilities are required to fly drones. Instead of focusing on giving evidence that supports the idea that drones do not negatively affect people's privacy, Colin offers evidence that is related to the idea that flying drones is a sport. It follows that his argument is weak because it has not been adequately substantiated.
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If LaL turns into a gel when exposed to a sample, it means the sample is contaminated with gram-negative bacteria
It is true that If LaL turns into a gel when exposed to a sample, it means the sample is contaminated with gram-negative bacteria.
Both the color and the turbidity of LAL are used to identify endotoxins. The mixture turns yellow when the kinetic chromogenic LAL reagent reacts with endotoxins. By looking for pyrogenic responses in horseshoe crab blood cells, this identifies the presence of bacterial endotoxins. The outer membrane of Gram-negative bacteria contains endotoxins. In order to ensure product safety and quality in the medical and pharmaceutical industries, their detection is essential. Gram-negative bacteria's outer membrane and cell wall are primarily made up of endotoxins.
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(complete question)
If LaL turns into a gel when exposed to a sample, it means the sample is contaminated with gram-negative bacteria.
true or false.
Geographic isolation can cause which of the following?
a Hybridization
b Allopatric Speciation
c Sympatric Speciation
d Polyploidy
How do you solve pedigree analysis?
Pedigree analysis is a method used to determine the mode of inheritance of a genetic trait or disorder within a family. The process involves constructing a family tree (pedigree) and analyzing the pattern of inheritance of the trait or disorder in relation to the family tree.
The following steps can be used to solve a pedigree analysis:
Construct a pedigree by gathering information about the family history of the trait or disorder. This includes information about the affected and unaffected individuals, their relationships to each other, and the generation in which the trait or disorder first appeared.Identify the pattern of inheritance by analyzing the transmission of the trait or disorder within the family. This can include identifying dominant or recessive inheritance patterns, X-linked inheritance patterns, or multifactorial inheritance patterns.Identify the possible mode of inheritance by comparing the observed pattern of inheritance to the known patterns of inheritance for the trait or disorder.Confirm the mode of inheritance by performing genetic testing, such as DNA sequencing or linkage analysis, on affected individuals and their family members.To know more about Pedigree, click here,
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One strategy for dealing with agricultural pests is integrated pest management (IPM). Describe IPM. As part of your description include TWO specific pest control approaches that are part of IPM.
One strategy for dealing with agricultural pests is integrated pest management (IPM). IPM is a pest control method with non-chemical substances. As part of your description include TWO specific pest control approaches that are part of IPM namely exclusion, and sanitation.
Integrated Pest Management is an approach that integrates various types of pest control methods with priority to non-chemical use. The Integrated Pest Management (IPM) system can be used in various types of industries such as the food, feed, plantation, oleochemical, and packaging industries.
Specific pest control approaches that are part of IPM, namely exclusion measures, namely by preventing the entry of the spread of organisms into an area and sanitation, namely monitoring so that pests do not spread to humans. IPM pest control is to prioritize not using chemicals, if you have to use pesticides, you will choose products that are safe for humans.
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What is a unit of seed?
A unit of seed is the structure generally regarded as a seed in planting practices and in commercial channels.
The seed is the embryonic stage of the factory life cycle. utmost seeds correspond of three corridor embryo, endosperm, and seed fleece. The embryo is a bitsy factory that has a root, a stem, and one or further leaves. The endosperm is the nutritional towel of the seed, frequently a combination of bounce, oil painting, and protein.
Commercial channels means the trade of the commodity for which a commodity commission is established for use as food, artificial, agrarian or chemurgic use, when vended to any marketable buyer or to any person who resells the commodity or any product deduced therefrom.
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Do whales breathe oxygen or carbon dioxide?
Whales are mammals, not fish. This means that, like all land mammals, they breathe oxygen through their lungs.
Whales and dolphins are mammals, and like us, they breathe air into their lungs. Because they do not have gills, they cannot breathe underwater like fish. Whales are mammals just like humans. Therefore, they have lungs and breathing air on their surface. It cannot extract oxygen from water like fish do with their gills. Whale inhalation is "conscious". The respiratory function of these animals is under the voluntary control of the central nervous system "CNS".
Whales accumulate carbon in their bodies during their long lifespans. When they die, they sink to the bottom of the ocean. Each large whale binds an average of 33 tons of carbon dioxide and removes this carbon from the atmosphere over centuries. Trees, on the other hand, only absorb up to 48 pounds of CO2 per year
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Why is a percentage scale used for the x-axis rather than actual ages? A) Researchers dont know the maximum life span of the organisms. B) This scale allows you to compare species with widely varying life spans on the same graph. C) The range of the actual ages would be too large to fit on the graph. D) For any graph, the x-axis and y-axis must use the same units.
It allows researchers to compare species with widely varying life spans on the same graph, the range of the actual ages would be too large to fit on the graph.So the correct option is c.
When discussing the life spans of organisms, it is common to use a percentage scale rather than actual ages on the x-axis of a graph. There are several reasons for this.
First, researchers do not know the maximum life span of the organisms that they are studying. By using a percentage scale, they can compare species with widely varying life spans on the same graph without having to worry about one species having a much longer lifespan than the others.
Second, the range of the actual ages would be too large to fit on the graph. By using a percentage scale, the data can be more easily visualized and compared.
Finally, for any graph, the x-axis and y-axis must use the same units. By using a percentage scale on the x-axis, the researcher can easily use the same units on both the x-axis and y-axis, making the data easier to compare and interpret.
In conclusion, a percentage scale is used for the x-axis of a graph when discussing the life spans of organisms because it allows researchers to compare species with widely varying life spans on the same graph, the range of the actual ages would be too large to fit on the graph, and the data can be more easily visualized and compared if the same units are used on both the x-axis and y-axis.
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Why do cancer cells divide and multiple uncontrollably?
Answer:
Most cancer-causing DNA changes occur in sections of DNA called genes. These changes are also called genetic changes. A DNA change can cause genes involved in normal cell growth to become oncogenes. Unlike normal genes, oncogenes cannot be turned off, so they cause uncontrolled cell growth.
A high relative humidity and sunshine hinder heat loss from the body by their adverse effects on the body, respectively, as:
The correct option (C) decreased evaporation and increased radiation.
Why does relative humidity climb the most just before dawn?
The ability of the air to hold water vapor increases with temperature. As a result, relative humidity rises as the temperature rises and reduces as it approaches the dew point. Around daybreak, when the nighttime low temperature is generally quite close to the dew point, the relative humidity is typically at its peak.
How does a high relative humidity affect things?
The "Heat Index" is the name given to this combined impact. The heat index increases with increasing air temperature and/or relative humidity, making the outside air seem hotter to our bodies.
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A high relative humidity and sunshine hinder heat loss from the body by their adverse effects on the body, respectively, as:
A. increased condensation and radiation
B. increased convection and radiation
C. decreased evaporation and increased radiation
D. decreased condensation and decreased radiation
E. increased evaporation and increased convection
Does stomach lining, liver, skin repair itself the fastest
The stomach lining is able to heal itself the fastest, followed by the skin, and then the liver.
What do you mean by the stomach lining?
The stomach lining is the innermost layer of the stomach, made up of cells that produce digestive enzymes and secretions that help break down food. This layer also helps protect the stomach from the acidic environment within the stomach.
The stomach lining is able to heal itself quickly because it contains specialized cells that can quickly make new tissue to replace damaged cells. The skin is also able to heal quickly because it is made up of many layers of cells that can quickly reproduce to form new skin. The liver is able to regenerate itself, but it takes longer than the stomach lining or skin because the liver is made up of fewer cells and the process of regeneration is more complex.
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What must cells do as they reach the limit of their surface area to volume ratio?
As cells reach the limit of their surface area to volume ratio, they must employ certain strategies in order to survive and continue to grow.
The primary strategy that cells use to survive and continue to grow when they reach the limit of their surface area to volume ratio is to divide. Cell division is the process of one cell splitting into two identical daughter cells. This process is essential for cellular growth, as it allows the cell to divide its surface area and volume, thus lowering its surface area to volume ratio. This allows the daughter cells to exchange material with their environment more efficiently than the original cell did.
Another way that cells can increase their surface area to volume ratio is by forming protrusions from their surface. These protrusions, also known as microvilli, are small folds of the cell membrane that increase the cell’s total surface area. This allows the cell to exchange material with its environment more efficiently, and thus allow it to continue to grow.
Cells can also increase their surface area to volume ratio by forming internal structures known as vacuoles. Vacuoles are small, membrane-bound structures that are filled with various substances, including water and enzymes. These substances can help the cell exchange materials with its environment more efficiently, thus allowing it to continue to grow.
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What do snails and clams have in common?
The common characteristics of snails and clams is that both belong to the phylum Mollusca and posses a calcareous shell on their body.
The phylum Mollusca is the second largest phylum of the kingdom Animalia. These are the invertebrate animals that are characterized by the presence of a calcareous shell on their body. The example of Mollusca are: snails, oysters, etc.
Shell is the outermost skeleton of organisms of Mollusca. It is made of calcium carbonate as the main constituent. The shell may be present only on the upper side of the body. Or it may be present on both the side, such animals are referred to as bivalves.
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