the diagram shows a beaker of water and molecules of black dye at the beginning of an experiment (time 1) and the same beaker of water and molecules of black dye after 30 mins (time 2)
a. b. molecules of water moved by osmosis from a lower solute concentration to a higher solute concentration
b. a, molecules of black dye moved by diffusion from a lower solute concentration to a higher solute concentration
c. d, molecules of water moved by osmosis from a higher solute concentration to a lower solute concentration
d. a, molecules of black dye by diffusion from a higher solute concentration to a lower solute concentration
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Answer: D
Explanation:
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Describe how the banks of a river are changed over time by both weathering and erosion
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Help me please!!!!!!!!!!
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Answer: B maybe
Explanation: what grade are you in
For the red onion skin experiment, in what cellular structure is red onion pigment stored and you were observing shrinkage?.
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In an onion, there are no chloroplasts because the onion cells cannot photosynthesize. The central vacuole is where the purple pigment (anthocyanin) that gives red onions their red color is housed, making it quite visible.
Define Plasmolysis.In order to better understand plasmolysis and deplasmolysis in red onion cells, this experiment aims to detect water transport into and out of cells. Plasmolysis takes place when concentrated sucrose solution—which has less water potential than onion cells—is given to the environment around epidermal red onion cells. Deplasmolysis is the term used when this process is reversed. When pure water is added to the onion cells' external environment, deplasmolysis can be seen. As water is pulled into the cells during deplasmolysis, the protoplast inside the cell enlarges to its former size. These findings can be compared to similar procedures in other plant cells.
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as dna replication continues and the replication bubble expands, the parental double helix is unwound and separated into its two component strands. this unwinding and separating of the dna requires three different types of proteins: helicase, topoisomerase, and single-strand binding proteins.
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The helicase binds at the replication fork by breaking the H-bonds between the bases. The topoisomerase binds ahead of the replication fork, breaks covalent bonds in DNA backbone. And the single-strand binding proteins bind after the replication fork, prevents H-bonds between bases.
The replication fork is the region of DNA where the DNA unwinds so as to make the replication of DNA possible. Two replications forks are formed one on each side when the DNA is in unwound state. Replication fork is Y-shaped structure.
Topoisomerase is the enzyme required for relaxation of the supercoiling of DNA during its formation of the replication fork.
The given question is incomplete, the complete question is:
As DNA replication continues and the replication bubble expands, the parental double helix is unwound and separated into its two component strands. This unwinding and separating of the DNA requires three different types of proteins: helicase, topoisomerase, and single-strand binding proteins. Write down the site of binding of the three proteins.
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what is the least number of trnas that can be used to recognize all of the codons of isoleucine, and what is/are the anticodon(s)? (in the answer choices, i
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Transfer RNAs have three base sequences (3'-5') known as anticodons that can recognize and base pair with mRNA codons in the 5'-3' direction.
Anticodons:
anticodons are nucleotide sequences that are complementary to codons. They are located in tRNAs and allow tRNAs to align the right amino acid with an mRNA during protein synthesis.
During protein formation, amino acids are strung together like beads on a necklace. Because amino acids have diverse characteristics, it is critical that the correct amino acids are employed in the precise areas. Putting the incorrect one in the wrong place might render a protein ineffective or even hazardous to the cell.
This image depicts a developing protein chain. The bottom left shows tRNAs carrying amino acids entering the ribosome complex.
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reproduction requires fusion of male cells in the pollen grain with female cells in the ovule
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Answer:
I didn't get the question but what I know is reproduction of seeds happens when the Male sex cells fertilizes the female sex cells and that happens when the nether produces pollen and the pollen is transferred to stigma which is a part of the female cells and the pollen send a pollen tube down through the style to the ovary which contains the ovule and the Male gametes nucleus enters an egg cell and fuses with the egg cell nucleus
which trait is commonly found in both of these two groups: chondrichthyans (cartilaginous fishes) and osteichthyans (bony fishes).
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Breathe via the gills. Fish with bones and fish with cartilage both have jaws in their mouths.
Describe the chondrichthyans and Osteichthyes.Chondrichthyes:
The second category of fish is the Class Chondrichthyes, which contains sharks, rays, and chimaeras. Sharks are among the oldest fish species to have a jaw. Their upper and lower jaws are made of cartilage. A shark can grow teeth indefinitely, but neither you nor I can have more than two sets. Because they regularly replace lost or damaged teeth with brand-new ones, sharks never run out of teeth.
Osteichthyes:
The Osteichthyes, or true bony fish, are the third major category of fish and are further classified into two divisions. The first class, known as the Sarcopterygii, is the more ape-like of the two classes. This class includes all terrestrial vertebrates, including cows and humans, as well as fish like coelacanths and lungfish.
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How does the water cycle affect the world's oceans and marine life?
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Answer:
Water evaporates from the surface of the ocean, mostly in warm, cloud-free subtropical seas. This cools the surface of the ocean, and the large amount of heat absorbed the ocean partially buffers the greenhouse effect from increasing carbon dioxide and other gases.
How do legumes plants help to reduce green house gases in the environment ?
Answers
Legumes such as peas, beans, soybeans, clover, and alfalfa can thus help to reduce greenhouse gas emissions of carbon dioxide as well as nitrous oxide in comparing to nitrogen-fertilized crops. Reduced use of fossil energy in food and feed production.
What are greenhouse gases?Greenhouse gases (also known as GHGs) are gases that trap heat in the earth's atmosphere.
The sun shines through the atmosphere during the day, warming the earth's surface. The earth's surface cools at night, releasing heat back into the atmosphere.
In comparison to nitrogen-fertilized crops, legumes such as peas, beans, soybeans, clover, and alfalfa can help to reduce greenhouse gas emissions of carbon dioxide and nitrous oxide. Reduced reliance on fossil fuels in food and feed production.
Thus, this way, legumes plants help to reduce green house gases in the environment.
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which selection best describes the initial event in contraction? view available hint(s)for part e ca2 flows into the cytoplasm and binds to troponin (thin filament) effecting a shape change that exposes myosin binding sites and removes the blocking action of tropomyosin, which had previously overlain the binding sites. once myosin binds to actin to form cross bridges, contraction begins. ca2 release ends when the ap ceases. which selection best describes the initial event in contraction? tropomyosin binds to myosin heads and actin bridges with tropomyosin. myosin heads bind to the newly exposed myosin-binding sites on actin to form cross bridges. the myofilaments slide closer together. calcium binds actin to myosin to begin the cross bridge cycle.
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The selection that best describes the initial event in contraction is that myosin heads bind to the newly exposed myosin-binding sites on actin to form cross bridges that is option B is correct.
This is the process describing the contraction of muscles of the body of human beings. The two filaments responsible for the contractive action of the muscle are actin and myosin. Muscle contraction occurs due to the relative movements of the two filaments that is actin and myosin. These filaments slide past one another which results in the contraction of muscles. The basis for this movement on the molecular level can be explained by the binding of myosin filament to the actin filament which allows the myosin filament to act as the driving force resulting in sliding of filaments over one another and this leads to muscle contraction.
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1. if humans are responsible for environmental changes that cause increases in the populations of native species, under what conditions should we work to reverse these population increases?
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Humans can reverse population increases through a species' food supply, culling, administering contraceptives, and a healthier living.
By reducing the number of unwanted children and implementing family planning programs that provide access to contraception, good sex education programs and family planning initiatives improve the lives of family members by enabling them to make the most of their resources and stay out of situations where they face poverty, hunger, or disease.
In addition, smaller families are also a result of lower child mortality brought on by better access to healthcare and economic opportunities. Global justice, ethical trade, and international assistance are all tools for reducing the world's population to levels that can be sustained. In this way, humans can control population and reverse environmental changes that they have caused.
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creation of an opening between the skin and kidney to drain urine to an external receptacle when ureters are unable to do so is called
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The creation of an opening between the skin and kidney to drain urine to an external receptacle when ureters are unable to do so is called nephrostomy.
What is nephrostomy?The kidneys аre mаde up by three externаl lаyers, which include the renаl fаsciа (the outermost lаyer), the perirenаl fаt cаpsule, аnd lаstly, the innermost lаyer, the renаl cаpsule, which then surround the spаce of the renаl cortex.
А nephrostomy is аn opening between the kidney аnd the skin. А nephrostomy tube is а thin plаstic tube thаt is pаssed from the bаck, through the skin аnd then through the kidney, to the point where the urine collects. Its job is to temporаrily drаin the urine thаt is blocked. This аllows the kidney to function properly аnd protects it from further dаmаge. It аlso helps cleаr аny infection.
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match each term with its definition. you are currently in a labeling module. turn off browse mode or quick nav, tab to items, space or enter to pick up, tab to move, space or enter to drop. a sequence of dna located upstream of a gene that signals the start of transcription a regulatory protein that blocks transcription by binding to the operator site a transcriptional element that blocks the signal between enhancers and promoters a gene that controls the expression of one or more genes by promoting or inhibiting transcription a small molecule that activates transcription by inhibiting the action of a repressor protein a short sequence of dna located near the promoter region that is recognized by a repressor protein answer bank
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A promoter is a segment of DNA that is upstream of a gene and marks the beginning of transcription.
What is DNA?DNA stands for deoxyribonucleic acid. It is defined as a sophisticated molecule that carries all the data required to create and maintain a creature.
Repressor: a transcription factor that binds to the operator of a gene to block the creation of mRNA. Insulator: a component that obstructs the signal between enhancers and promoters. A gene that affects transcription to promote or inhibit the expression of one or more genes Regulational gene. A tiny chemical that stimulates transcription by preventing repressor protein activity. A small segment of DNA close to the promoter region called the inducer is identified by the repressor protein.
Thus, a promoter is a segment of DNA that is upstream of a gene and marks the beginning of transcription.
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. which parable describes the problem of wild animals that are hunted to the point of extinction? a. coase theorem b. tragedy of the commons c. cost-benefit analysis d. clean air act
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The perimeter that describes the problem of wild animals that are hunted to the point of extinction is option B: tragedy of the Commons.
The tragedy of the commons is a philosophical idea that emphasizes the tension between individual and group rationality. Natural resources, such as water and biodiversity, are vulnerable to overexploitation when people use them for their own personal gain without taking society as a whole into account. This is further threatening the wild life to extinction due to the limitation of common resources.
In both economics and environmental science, it is problematic when people use a shared resource for their own benefit at the expense of others, known as the tragedy of the commons. This may lead to excessive consumption, underinvestment, and resource depletion.
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which method of microbial control does not rely on denaturing proteins and/or disrupting the integrity of the cell membrane?
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Lyophilization method of microbial control does not rely on denaturing proteins and/or disrupting the integrity of the cell membrane.
Lyophilization, also known as freeze drying, is a process in which water is removed from a frozen product and placed under a vacuum, allowing the ice to transition from solid to vapor without passing through a liquid phase. Lyophilization is a water removal process that is commonly used to preserve perishable materials, extend shelf life, or make the material more transportable. Lyophilization involves freezing the material, then lowering the pressure and increasing the heat to allow the frozen water in the material to sublimate.
Liquid nitrogen can be used successfully and economically instead of mechanical refrigeration for lyophilization/pre-freezing, increasing viability and yield. It also improves performance and reliability while requiring less capital investment than mechanically based systems.
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which of the following is not a major function of protein in the human body?
A. Synthesis of hormones
B. Growth and maintenance of new tissue
C. Maintaining fluid balance
D. Providing energy to the body
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Answer: D
Explanation:
(HELP QUICK !!!!).
What type of results in genetic expression do you think may occur if even one nucleotide is not correctly transcribed from the DNA to the RNA? explain your answer.
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If one nucleotide is the incorrect one that means that it is a transition or a transversion. Transition or transversion mutants may lead to no change in the protein sequence (known as silent mutations), change the amino acid sequence (known as missense mutations), or create what is known as a stop codon (known as a nonsense mutation). Genetic expression may remain the same if the mutation does not occur in the promoter region however a pre-mature stop codon would cause a truncated protein to be created.
What do you mean by genetic expression?Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect.
Moreover, some simple examples of where gene expression is important are: Control of insulin expression so it gives a signal for blood glucose regulation.
Therefore, gene expression is primarily controlled at the level of transcription, largely as a result of binding of proteins to specific sites on DNA.
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serotonin (5-hydroxytryptamine, 5-ht) is a neurotransmitter with receptors (5-ht receptors) located in cells throughout the body. there are more than a dozen different types of serotonin receptors that fall into several different classes. one class consists of serotonin-activated ion channels and the other receptor classes are g-protein-coupled receptors that associate with different g proteins. the 5-ht7a receptor couples to gs and activates adenylyl cyclase, while the 5-ht2b receptor couples to gq and activates phospholipase c. the diversity of receptor types has led pharmacologists to search for drugs that will bind to and modulate just a single receptor class in order to limit systemic side effects (see 5-hydroxytryptamine receptor subtypes and their modulators with therapeutic potentials). place into bins the downstream effects predicted for a drug that exclusively activates the 5-ht7a receptor versus a drug that exclusively activates the 5-ht2b receptor.
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Tryptophan serves as the starting material for the central and systemic synthesis of the monoamine neurotransmitter 5-hydroxytryptamine, also known as serotonin.
What does 5-HT (5-hydroxytryptamine) (serotonin) mean?Serotonin has been found to bind to 14 physically and functionally different receptor subtypes, each of which mediates the action of neurotransmitters by way of a cascade of downstream signalling molecules and effectors.
Serotonin is involved in many fundamental physiological processes, including apoptosis, mitochondrial biosynthesis, cell proliferation, and migration. Despite being most frequently discussed for its role in the pathogenesis of neuropsychiatric and mood disorders, serotonin also plays a role in many other basic physiological processes. increase. Anorexia nervosa, cancer, and other pathogenic diseases exhibit its neurotransmitter function.
We carefully vetted the serotonin and its receptor-related molecular reactions from the available literature using a strict set of NetPath annotation criteria. Gene regulation at the transcriptional and translational levels, molecular association, activation/inhibition, post-translational modification, transport, and other categories of responses were also included.
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What is true about changes to biotic factors in an ecosystem?
Responses
It doesn't affect the living parts of an ecosystem.
It can result in populations of organisms increasing.
It results in changes to salinity or temperature.
It affects food chains but not the overall food web.
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Answer:
It results in changes to salinity or temperature
Explanation:
Biotic things have to do with non living things that affect an ecosystem and if a biotic factor is changed like the sun it will affect the ecosystem so if the sun is taken away It results in changes to salinity or temperature
How is continental crust different from oceanic crust? question 5 options: continental crust is more dense and lighter. continental crust is thicker and more likely to sink. oceanic crust is thinner and more likely to sink. oceanic crust is thicker and more dense.
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In comparison to oceanic crust, which is typically 5-10 km thick, continental crust is often 20–70 km thick. Oceanic crust is more recent and has a density of 3 g/cm3, whereas continental crust is older and less dense (2.7 g/cm3).
What distinguishes the oceanic crust from the continental crust?When compared to oceanic crust, which is basaltic (i.e., richer in iron and magnesium than granite) and has a density of around 2.9 to 3 grammes per cubic cm, continental crust is generally granitic and has a density of about 2.7 grammes per cubic cm.
Is crust from the oceans denser than crust from land?Dark-colored rocks known as basalt and gabbro make up the majority of the oceanic crust. It is lighter-colored rocks called andesite and granite that make up the continental crust, which is thinner and denser. Because of its low density, continental crust "floats" high above the viscous mantle, forming dry land.
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you are carrying out a chromatin immunopreciptation experiment. at the step where you are supposed to add the antibody to your protein of interest, you accidentally add a mixture of antibodies that someone was storing in the lab. what will your results show?
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The results of the chromatin immunoprecipitation experiment are that the DNA will still be isolated, but it will respond to DNA that was bound by any protein recognized by the antibody.
Chromatin immunoprecipitation (ChIP) may be a sort of immunoprecipitation test procedure utilized to investigate the interaction between proteins and DNA within the cell.
ChIP too points to deciding the particular area within the genome that different histone alterations are associated with, demonstrating the target of the histone modifiers.
It points to deciding whether particular proteins are related to particular genomic locales, such as translation variables on promoters or other DNA authoritative locales, and possibly define cistromes.
ChIP is vital for the headways within the field of epigenomics and for learning more about epigenetic marvels.
Chromatin immunoprecipitation (ChIP) could be a strategy utilized to decide the area of DNA authoritative locales on the genome for a specific protein of intrigue.
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As part of his voyage on the beagle, darwin spent about 5 weeks off the coast of ecuador making observations on the.
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Charles Darwin spent around 5 weeks off the coast of Ecuador conducting observations on the Galápagos Islands. His visit to the Galapagos Islands was part of his expedition on the Beagle.
Where is Galapagos Island located?The Galapagos Islands are famous for their enormous number of unique species and the research carried out by Charles Darwin that led him to the theory of natural selection. The Galápagos Islands, also known as the Galapagos, are an archipelago of 13 volcanic and mountainous islands. The Galapagos Islands are located in the Pacific Ocean approximately 1,000 kilometers west of South America's coast. The Galapagos Islands are constitutionally part of Ecuador. In 1959, the Galapagos Islands were declared a natural reserve. In 1978, UNESCO designated the Galapagos Islands as a World Heritage Site.
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a chromosome has undergone a translocation mutation that has completely deleted its centromere region, preventing association with spindle fibers. what will be the fate of this cell?
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The centromere region of a chromosome has been totally destroyed by a translocation, prohibiting interaction with spindle fibres.
A single chromosome becomes two after DNA replication when it has experienced?A chromatid is one of the two identical halves of a chromosome that has undergone replication ahead of cell division. The two "sister" chromatids are connected at the centromere, a constricted region of the chromosome.
A crossing over in meiosis is when genetic material is exchanged between cells?When it comes to genetics and genomics, the term "crossing over" describes the DNA exchange that takes place between paired homologous chromosomes (one from each parent) during the formation of egg and sperm cells (meiosis).
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the evolution of photosynthesizing organisms on earth and the development of an oxygen-rich environment led to a rapid diversification of life. explain why there is an evolutionary advantage to an organism that requires oxygen to live compared to one that does not require oxygen.
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A quick diversity of life was triggered by the emergence of an oxygen-rich environment. Much more energy can be produced by them.
What is an example of an organism?A living item is considered an organism if it has an organised approach, can respond to stimuli, reproduces, grows, adapts, and maintains homeostasis. So every living thing on Earth that is an animal, plant, mushroom, protist, microbe, or archaeon qualifies as an organism.
Is the human body a living thing?A live item is understood to be an organism. The definition of a living entity is consequently anything that has cells as its fundamental unit of organization and is capable of sustaining life. Various types of living things include: Humans.
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approximately how many more mammal species become extinct in the period 1901-2000 than became extinct in the period 1801-1900?
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90 mammal species become extinct in the period 1901-2000 than became extinct in the period 1801-1900.
Extinction is a situation in which something no longer exists. Their can be many reasons associated like species have been hunted to the point of extinction, scarcity of food or natural disasters.
Their are two main types of extinction firstly Mass extinction that has occurred only five times in history. The other is Background extinctions which occurs over longer period of time and are considered important in natural extinction rate.
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True or False) DNA does not have to break apart to be copied.
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Answer: false
Explanation: needs to break apart to prevent the risk of having an uneven number of chromosomes that can lead to developmental disorders and cancer.
the medulla is located directly above the spinal cord in the hindbrain and controls
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The medulla is located directly above the spinal cord in the lower part of the brain stem and controls many vital autonomic functions such as heart rate, breathing, and blood pressure.
What is nervous system?
The brain, spinal cord, and a sophisticated nerve network are all parts of the nervous system. The brain and the body are communicated with via this system.All bodily functions are managed by the brain.From the brain, the spinal cord descends via the back. It is made up of strands of nerves that branch out to every organ and area of the body. The brain sends and receives messages via this network of nerves to various parts of the bodyPart of nervous system:
The central nervous system and the peripheral nervous system make up the nervous system:The brain and spinal cord are components of the central nervous system.The nerves that run throughout the entire body are a part of the peripheral nervous system.Medulla:
medulla oblongata is the bottom-most part of your brain. Its location means it's where your brain and spinal cord connect, making it a key conduit for nerve signals to and from your body. It also helps control vital processes like your heartbeat, breathing and blood pressure.Hence, medulla controls heart beat, breathing rate and blood pressure.
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in what ways do virions resemble living cells? choose one or more:a.some virions possess genes for trna.b.they are capable of protein synthesis.c.they possess genes that can direct their own replication.d.some virions exhibit flagellar motility.e.their genomes can be larger than some cellular genomes.
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Virions resemble living cells as their genomes can be larger than some cellular genomes.
What is genomes?The genome is a cell's whole collection of DNA instructions. The genome of humans is made up of 23 pairs of chromosomes found in the cell's nucleus, as well as a tiny chromosome placed in the cell's mitochondria. A genome includes all of the information required for a person to develop and operate. Our genome is made up of DNA and contains this collection of instructions. Every cell in the body, such as a skin cell or a liver cell, has the same set of instructions: Our genome's instructions are made out of DNA. DNA has a one-of-a-kind chemical code that governs our growth, development, and health.
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describe the process of dna replication in eukaryotic cells. make sure to include the proteins required for this process and highlight what aspects of this process are different from dna replication in prokaryotic cells.
Answers
In eukaryotes, DNA replication takes place in three stages: beginning, extension, and a process involving numerous enzymes or other proteins.
What are cells and what do they do?The fundamental units of all life forms are cells. There are numerous trillions of cells in a body. They give the body structure, absorb nutrients from meals, turn those energy into energy, and perform certain tasks.
What is the structure of cells?The membrane protein, the nucleus, and the cytoplasm are the three components that make up a cell. Intricate arrangements of microscopic fibers and tens or hundreds of tiny, unique structures known as organelles can be found in the cytoplasm.
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Following a disturbance to a site, only some species that arrive at the site survive. Once an individual plant establishes itself, it modifies the environment, for example by changing resource availability. The plant is then replaced by a member of a species better suited to the modified environment, and then the process continues. Which model of succession best explains this pattern?.
Answers
The model of succession that best explains the problem at hand Is the Tolerance model of succession.
In the problem, we have been told that the plant kind of inhibits the freshly attained site and then flourishes which makes it seem like the facilitation model. But we have also been told that the plant is soon replaced by other plants that are most suitable to live on that site.
The tolerance model is the proper explanation for this as it states that all species are capable of establishing themselves but only the ones that have a bigger population become dominant. This proves that the example in question is an example of the Tolerance model.
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