• BUY NOW, OR CONTACT ME:
  • Independent Business Representative

Science of Cellular Repair




What Are Some Interesting Facts About Nucleic Acids?

NequeNucleic acids are DNA, mRNA, and tRNA, and they are the building blocks of life. Each nucleic acid is made of up five parts: uracil, thymine, cytosine, adenine and guanine.

Humans need 20 amino acids and five nucleotides to survive. Nucleotides are made of a five-carbon sugar, a nitrogen base and an ion of phosphoric acid.

DNA, or deoxyribonucleic acid, is one of the most important nucleic acids in the human body. It contains special genetic code for every cell in the body. In essence, DNA is a long, double-helix chain of nucleotides and the nucleic acid in each strand of DNA must be able to replicate itself during cell division.



What Is the Function of Nucleic Acids?

Nucleic acids are organic compounds that both store genetic information and transfer it during cell division. DNA holds the genetic codes necessary for the creation of new cells, while the RNA uses the genetic codes in the DNA to synthesize and create new proteins during cell division,

DNA, or deoxyribonucleic acid, is essentially the storage unit for the building blocks of life. The RNA, or ribonucleic acid, uses the information stored in the DNA to facilitate and regulate protein synthesis, according to Tutorvista.com. From within a cell's nucleus, DNA passes genetic code to RNA, which in turn uses the code to shape the newly made proteins. RNA uses the genetic code by converting it into amino acids which can then be used to make up new proteins.

RNA can be broken down into three specific nucleic acids: t-RNA, m-RNA and r-RNA. The t-RNA is the nucleic acid that delivers the amino acids to the area where protein synthesis occurs. The m-RNA receives the genetic messages from the RNA and processes it for delivery. Lastly, r-RNA is the nucleic acid that makes up a large portion of a cell's ribosome and contributes to the stability of the m-RNA.



What Two Functions Do Nucleic Acids Have?

According to About.com, two functions of nucleic acids are passing genetic information to the new generations (new cells within an organism or offspring) and coding in protein synthesis. As Wikipedia explains, the first is carried out by deoxyribonucleic acid, or DNA, while protein synthesis is regulated by ribonucleic acid, or RNA.

Both DNA and RNA are nucleotide polymers, with sugar and phosphate groups as a backbone. Under the effect of external or physiological mutagens (substances that can change or damage the structure of DNA), genetic information stored in DNA is altered, Wikipedia explains. When the amount of damage surpasses the DNAs ability to self-repair, the mutations lead to the synthesis of less effective or even completely defective proteins, which leads to aging and disease development.



What Are the Two Types of Nucleic Acids Called?

The two types of nucleic acids are deoxyribonucleic acid, or DNA, and ribonucleic acid, or RNA. DNA can be found in most living organisms and is found in the nucleus of living cells. RNA converts genetic information found in genes into amino acid sequences.

Proteins are built within the body to specifications found in the cells. Because the system is so complex, there is a lot of information needed and this information details the structure of the proteins. The nucleic acids are a set of molecules found in each cell around the body and are made of sugar and phosphate bonded together in a long chain.

Each nucleic acid can bond to only four nucleotide bases; however, millions of these four bases are bonded to them. DNA is named after the sugar that is used in its backbone, deoxyribose and is significant due to its structure with the bonds of the nucleotide bases. The four nucleotide bases is can connect to are, adenine (A), cytosine (C), guanine (G) and thymine (T). The molecule of DNA is double stranded, and the adenine bonded with sugars always bond with thymine on the other strand and guanine bonds with cytosine, forming the double helix structure.

Like DNA, RNA has a sugar and phosphate backbone and bonds with four nucleotide bases. The sugar in RNA, however, ribose rather than deoxyribose and RNA only has a single strand. Unlike DNA, RNA does not bond with thymine, but bonds with uracil (U). RNA is needed to build proteins in living organisms and can move around the cells of the body relaying information stored in the nucleus to other parts of the cell where proteins are made.



What Is a Nucleic Acid Polymer?

DNA and RNA are nucleic acid polymers. Nucleic acid is a macromolecule that serves as the binding for these two genetic substances. It is a staple of all organic life.

Nucleic acid is the binding used in the generation of genetic material. It is found in both deoxyribonucleic acid and ribonucleic acid, the two substances used for creating life and forming new cells. This material helps transfer, maintain and recreate DNA and RNA so as to encourage ongoing health and sustainability in living beings.

Nucleic acid polymers are identified along the chain by the acidic character of each group. Cytosine, guanine and adenine are present in both RNA and DNA. Uracil is only present in RNA and is switched with thymine. The sugar present in these chains dictate its identity. A DNA molecule contains deoxyribose, while RNA is made with ribose.

These acids range in size from small polymers to large chromosomes depending on what these structures are responsible for doing. Nucleic acids are formed from a complex series of sugars and phosphates, making it easy for other particles to bond with the available receptor sights. Carbons in the chain also assist with creating more connectivity and stability in pairings.



What Is the Purpose of DNA?

The primary purpose of DNA is to store hereditary information within the cells of all living things. It is a molecule that encodes the genetic instructions used in the development and functioning of all known living organisms.

DNA also facilitates biological synthesis specifically in the creation of RNA molecules and cellular proteins.

Information stored in DNA is in the form of a code consisting of four chemical bases: adenine, guanine, cytosine and thymine. These bases pair up with each other to form base pairs. This process is known as base pairing, and it occurs when the bases attach to one another through hydrogen bonds. Each base is attached to a sugar molecule and a phosphate molecule. Collectively, a base, sugar and phosphate form a nucleotide.

Nucleotides are arranged in two biopolymer strands called polynucleotides. Polynucleotides coil around each other in a double helix, which takes a form similar to a ladder's. Nucleotides are connected to one another in a chain by covalent bonds between the sugar of one nucleotide and the phosphate of the next. This sequencing of the bases that connect the two biopolymer strands determines the natural characteristics of the living thing in which that specific DNA exists.



Why Is DNA Called the Blueprint of Life?

Just as blueprints direct the building of a house, DNA molecules contain the genetic instructions used in the development and functioning of a living organism. The DNA of eukaryotic organisms such as plants and animals is organized into linear chromosomes and stored within the nucleus of every cell.

DNA has a double helix structure, which appears like a twisted ladder. The sides of the DNA ladder are composed of alternating deoxyribose sugar molecules and phosphate groups. The rungs of the ladder are nucleotide base pairs, which are the genetic information of the DNA. Each nucleotide can be adenine, thymine, cytosine or guanine. Genetic information is read in sequence of three bases called triplets. Each triplet codes for a specific amino acid during protein synthesis. As described by NobelPrize.org, when proteins are needed, the corresponding genes are transcribed from DNA into an RNA molecule. RNA is transported out of the cell's nucleus where proteins are built based upon translation of the RNA code. Proteins are an essential part of organisms and participate in every process within a cell.



Why Do We Need DNA?

Without DNA, life would not be able to perpetuate itself. DNA is needed as it is the blueprint of life. Every species of plants and animals contains a genetic substance called DNA that passes on the physical characteristics of an organism from one generation to the next.

DNA contains all information that tells a cell how to grow, elongate, and form tissues, organs and organ systems. DNA, which stands for deoxyribonucleic acid, is found in every living cell. Each cell contains a nucleus at the center; within the nucleus, there are a specific number of chromosomes. Every species has a fixed number of pairs of chromosomes. For instance, humans have 23 pairs of chromosomes.

A chromosome has three sections with a central portion called the centromere. The two ends of the chromosomes attached to the centromere are called chromatids. Inside the chromatids are strands of DNA.

DNADNA consists of a double helix or a double chain of nucleic acids that are coiled around like a spiral staircase. The four subunits, or nucleotides of human DNA are adenine, guanine, thymine and cytosine. These form genes that are the basis of various characteristics or physical traits. These four nucleotides are paired differently along the entire length of the DNA, giving rise to genes.



What Is the Purpose of DNA Replication?

DNA replicates in order for cells to divide, withy a parent cell divides giving each daughter cell the full DNA string in each nucleus. Without cell division, an organism cannot grow into a plant, a human or an animal. DNA replication allows all cells to contain the full genetic code for the body.

It replicates by unraveling each of the strands of DNA that make up the double helix. Because each of the four nucleotides can only connect to one other, each of the single halves of DNA act as a template to build the other half. The nucleotide thymine can only bond with adenine using two hydrogen bonds, and guanine can only bond with cytosine using three hydrogen bonds.



What Is the Purpose of DNA?

The primary purpose of DNA is to store hereditary information within the cells of all living things. It is a molecule that encodes the genetic instructions used in the development and functioning of all known living organisms.

DNA also facilitates biological synthesis specifically in the creation of RNA molecules and cellular proteins.

Information stored in DNA is in the form of a code consisting of four chemical bases: adenine, guanine, cytosine and thymine. These bases pair up with each other to form base pairs. This process is known as base pairing, and it occurs when the bases attach to one another through hydrogen bonds. Each base is attached to a sugar molecule and a phosphate molecule. Collectively, a base, sugar and phosphate form a nucleotide.

Nucleotides are arranged in two biopolymer strands called polynucleotides. Polynucleotides coil around each other in a double helix, which takes a form similar to a ladder's. Nucleotides are connected to one another in a chain by covalent bonds between the sugar of one nucleotide and the phosphate of the next. This sequencing of the bases that connect the two biopolymer strands determines the natural characteristics of the living thing in which that specific DNA exists.



What Is DNA and RNA?

DNA and RNA are nucleic acids, which are also considered polymers. Deoxyribonucleic acid is used to create ribonucleic acid that, in turn, contains the primary sequence of amino acids needed to make proteins.

While DNA and RNA are found in different parts of the cell and have different functions, they are always found together due to how they function. Without DNA, there would be no RNA to assist in the production of protein.

The DNA is located in the nucleus of the cell while RNA is found in the cytoplasm even though it is synthesized in the nucleus. Both of these cell components encode genetic information, but of the two, only RNA catalyzes biological reactions. Structurally, both of these polymers are unbranched meaning they are one long line of genetic building blocks. If either one of these polymers fails or were to disappear then life would cease to exist. Without both of these elements there would be no protein created, which is required for life to exist and to produce energy.

Both DNA and RNA are found in all living cells, no matter what species or kingdom they belong. These molecules are considered very large compared to other molecules that can be found in living organisms.



What Do DNA and RNA Have in Common?

RNA and DNA are both nucleic acid macromolecules that are comprised of a set of monomers known as nucleotides. They also both contain purines and pyrimidines as their bases and contain pentose sugars as their backbones.

RNA and DNA are both composed of nucleotides that are connected to a sugar backbone. However, RNA contains ribose as its sugar backbone, while DNA contains deoxyribose as its sugar backbone. The bases found in RNA and DNA are also different. They both contain the same three nitrogenous bases, including adenine, cytosine and guanine, but DNA contains thymine as its fourth base, while RNA contains uracil.



What Are Some Similarities Between RNA and DNA?

RNA and DNA are both molecules containing the genetic information that is necessary for life. Both molecules are composed of nucleotides, which are chemical structures consisting of a sugar, a phosphate and a nitrogenous base. Nucleotides are linked by alternating sugar and phosphate bonds.

Though the general structure of the nucleotides in both RNA and DNA is the same, there is a key difference. Each molecule contains a different type of sugar. The sugar in RNA is ribose, while the sugar in DNA is deoxyribose. The full names of DNA and RNA, deoxyribonucleic acid and ribonucleic acid, are derived from the different type of sugar in each molecule.

The alternating sugar and phosphate bonds create long strands in both DNA and RNA. The molecules differ in the number of strands making up each. DNA is double-stranded, shaped like a ladder with rungs between both sides. RNA is single-stranded.

The function of DNA is the storage of genetic information. DNA is located in the nucleus and must remain there. RNA travels from the nucleus through the cell's cytoplasm to the ribosome. It carries the information from the DNA to the ribosome so that it can be decoded to make proteins.

Genetic information is coded by using the chemicals adenine, guanine, thymine and cytosine in DNA. RNA uses the same chemicals as DNA to store genetic information, with the exception of thymine. RNA replaces thymine with a chemical called uracil.



What Is DNA Sequencing Used For?

DNA sequencing is used to identify individual genes within the DNA of any organism. This information can be used to identify variants and mutations that cause diseases and disorders.

The process of DNA sequencing is used today by researchers and physicians around the world. This is due in large part to the success of a research project known as the Human Genome Project, which began its work in 1990. The HGP sought to map all three billion base pairs of the human genome, according to the National Human Genome Research Institute.

Automatic sequencing machines read electrophoresis gels, resulting in faster and more accurate DNA sequencing. These machines can produce a rough draft of a DNA sequence of 20,000 to 50,000 bases in a few hours. First-generation DNA sequencing technology employed the Maxam-Gilbert method and the Sanger method. Finishing is a method that involves the final assembly of the raw sequences that come out of the sequencing machines. Newer sequencing technologies have made it possible to sequence the genomes of several organisms, including the mouse, the rat, a malaria-carrying mosquito and mustard weed.

Scientists can use sequence information to determine which sections of DNA contain genes. Scientists can analyze those genes for mutations that may cause disease. The sequencing of the human genome has given scientists a blueprint of the human being, allowing them to find answers for complex biological processes, including how a baby forms from a single cell, how the human brain works, and how genes regulate tissue and organ functions.

Genetic sequencing methods have helped scientists to discover more than 1,800 disease-causing genes and to create more than 2,000 genetic tests to identify medical conditions, according to the National Institute of Health.



What Are the Three Parts of a Nucleotide?

The three subunits of a nucleotide are a nitrogenous base, a sugar and a phosphate group. Nucleotides are the building blocks of DNA and RNA molecules.

One nitrogenous base, known as purine, is comprised of adenine and guanine. The other nitrogenous base is pyrimidine, which is cytosine and thymine. These bases combine to form DNA. RNA formation is slightly different, as uracil is substituted for thymine.

Deoxyribose is the sugar subunit in a DNA molecule, while ribose is the sugar subunit of an RNA molecule.

Nucleotides form nucleic acids, which are organic compounds that are found in every cell. These compounds are chemically linked to form DNA and RNA strands.



How Does DNA Differ From RNA?

DNA is a stable, double helix that functions in long-term storage of genetic material, while RNA is a reactive, single helix that transfers information. There are also slight differences in base pairs between DNA and RNA.

The sugar deoxyribose makes up DNA while RNA utilizes ribose. This means that DNA contains carbon to hydrogen bonds, making it very stable. RNA, on the other hand, contains more reactive oxygen to hydrogen bonds. The double helix structure of DNA involves small grooves that provide little space for enzyme attachment, but the single strand of RNA has larger, more spacious grooves. Because of these structural differences, DNA is much more stable and more suitable for long-term storage of genetic information as it degrades very little over time. RNA is fairly reactive and is subject to frequent recycling and reformation; this makes RNA a better candidate for the transference of genetic material. Both DNA and RNA use adenine, guanine and cytosine as base pairs, but DNA contains thymine while RNA contains uracil.

DNA is a self-replicating molecule, capable of replenishing itself whereas RNA forms, when the need arises, from DNA. Despite the relative stability of DNA, it is actually more vulnerable to damage from ultraviolet radiation than RNA.

DNA is self-replicating and serves the function of storing and transferring genetic data from one cell to another during reproduction through chromosomes. Chromosomes contain genetic information necessary for cell reproduction and the determination of individual traits in new organisms. RNA is synthesized from DNA, and its stored genetic information is utilized in proteins called amino acids. These proteins are delivered to cell components called ribsosomes, which are responsible for the determination of specific cell functions and gene expression.



Are DNA and RNA Polymers Composed of Monomers?

Both DNA and RNA polymers are composed of monomers. These monomers are called nucleotides. A nucleotide has four parts; however, the monomers of DNA and RNA differ slightly from each other, thus giving the molecules different structures and functions.

A nucleotide comprises a phosphate group, a five-carbon sugar and a nitrogenous base. The five-carbon sugar in DNA is deoxyribose whereas the sugar in RNA is ribose. Four different nitrogenous bases make up DNA and RNA, but the bases differ slightly. In DNA, the bases are adenine, thymine, cytosine and guanine; in RNA, the bases are the same except that uracil replaces thymine. Adenine and guanine are called purines; thymine, cytosine and uracil are pyrimidines.



How Do Cells Use Energy?

Cells use energy in order to grow, regulate metabolism and reproduce. This energy is obtained from a source such as food molecules or light from the sun, and through processes like glycolysis, the citric acid cycle and oxidative phosphorylation, an energy-rich molecule is then created. The cell can then use the energy in the protein molecule to help it function.

The powerhouse of an animal cell is called the mitochondria. In plants, chloroplasts carry out a similar function. Eukaryotic cells, or cells that contain a nucleus (which includes both plant and animal cells), can use three different modes to create energy molecules from an energy source.

Glycolysis, also known as fermentation, involves dividing a glucose (sugar) molecule into two molecules of a new substance called pyruvate. No oxygen is needed for this reaction, but if some is present, then the pyruvate molecules can enter the mitochondria to be transformed into two acetyl-CoA molecules and one carbon dioxide molecule. This particular energy process is called the citric acid cycle.

The third and final process is oxidative phosphorylation, which involves a gradient of protons forming as electrons pass through protein complexes in the inner membrane of the mitochondria.

If there is an abundant energy source present, cells can also make larger molecules to store for later, called polysaccharides and lipids (sugars and fats).



How Do Cells Get Energy?

Cells get energy in the form of food molecules if they are animal cells or sunlight if they are plant cells. The process used by all cells to create usable energy is quite similar, no matter the source of the energy.

Animal cells have semi-permeable outer membranes that allow some molecules, such as the sugars and fats that are necessary for the creation of energy, to enter the cell. Once these molecules are inside the cell, the bonds that hold them together are gradually broken down. Each time a bond is broken, it releases energy that the cell can either burn immediately or store for later use. Energy that is stored is reassembled in the form of ATP molecules. These molecules have bonds that are easy to break quickly whenever the cell needs energy.

Plants get the nutrients necessary for growth from molecules in the soil, water and air. However, unlike animals, they are not able to actively take in more nutrients in the form of food, so they need an alternate source of energy to create the chain reactions that break down the bonds of molecules to create energy for each cell. This energy comes from the sun, and plant cells are able to harness it using a chemical called chlorophyll, which enables photosynthesis.



What Is Released During Cellular Respiration?

According to the State University of New York, the major products released during cellular respiration are carbon dioxide, water and energy in the form of ATP molecules. These are all generated in several steps in the progressive breakdown of glucose molecules through reactions with oxygen and other molecules.

The State University of New York states that there are three major stages of cellular respiration. The first is glycolysis, which breaks a single glucose into two molecules known as pyruvate without needing oxygen. This process produces a net of two ATP molecules. Two more ATP molecules are produced in the next step, the citric acid cycle. Finally, oxidative phosphorylation produces 32 ATP molecules along with water and carbon dioxide.



What Are the End Products of Cellular Respiration?

The end products of cellular respiration are adenosine triphosphate, or ATP, molecules that the cell uses for a variety of processes. Cellular respiration yields 38 ATP molecules in prokaryotes and 36 ATP molecules in eukaryotes.

Cellular respiration is a method for cells to obtain the energy that is stored in food. It takes place in three stages: glycolysis, the citric acid cycle and electron transport. Some stages of the process require oxygen while some do not. Eukaryotic cells produce two fewer ATP molecules than prokaryotic cells during cellular respiration due to the passing of NADH molecules from glycolysis through the mitochondrial membrane.



At What Stage in Cellular Respiration Is Most ATP Produced?

In cellular respiration, the electron transport stage is when most adenosine triphosphate (ATP) is produced. Electron transport is the third stage in cellular respiration.

Cellular respiration involves a series of complex reactions. The first phase of cellular respiration is glycolysis, which involves splitting glucose. This phase is carried out in several steps. The end result is the production of pyruvic acid. After pyruvic acid is produced, the Krebs cycle begins. The Krebs cycle, which is the second phase of cellular respiration, is sometimes referred to as the citric acid cycle. The Krebs cycle first produces citric acid, and it produces carbon dioxide as an end product. Electron transport is the last stage of aerobic respiration in cellular respiration. It results in the production of adenosine triphosphate, or ATP. ATP is a molecule that supports a variety of life functions. It is found in the nucleoplasm and cytoplasm of all cells, and helps organisms perform physiological functions. During anaerobic respiration, ATP is synthesized through glycolysis. In aerobic production, ATP is produced by mitochondria in addition to glycolysis.

Glycolysis and ATP Production Glycolysis is produced in a cell's cytoplasm. During this phase, a molecule of glucose is broken down into two molecules of pyruvate. These two molecules then move on to the second phase of the cellular respiration process. The second phase, or the Krebs cycle, begins when the pyruvate molecules enter the mitochondrion. The Krebs cycle ends in a complete breakdown of the glucose molecule. During this phase, six carbon atoms combine with oxygen to produce carbon dioxide. The energy produced through chemical bonds in the Krebs cycle is then stored in a series of molecules. The electron transport phase involves the transformation of the energy produced in the Krebs cycle to ATP. As the energy is released, it travels down structures called electron transport chains, which are located in the mitochondrion. The energy makes hydrogen ions move across the inner membrane into the intermembrane space. Hydrogen ions then move back across the membrane with the help of channel proteins called ATP synthase. The end result of glycolysis is that it produces four molecules of ATP, which means that two molecules of ATP are gained during glycolysis.

Aerobic and Anaerobic Cellular Respiration Cellular respiration can be performed with and without oxygen. Cellular respiration that requires oxygen is called aerobic respiration. Cellular respiration that does not need oxygen is called anaerobic respiration. Anaerobic respiration first appeared when the earliest life forms arose on Earth and did not have access to oxygen. Oxygen began appearing on Earth around two or three billion years ago. At that point, living organisms could begin using oxygen to produce ATP. Most organisms use aerobic respiration instead of anaerobic respiration.

Uses of Cellular Respiration Plants and animals both use cellular respiration to perform life functions on a daily basis. Plants use it to perform photosynthesis, which provides the sustenance they need to stay alive. However, plants have a reverse cycle of cellular respiration, which produces oxygen as an end product. Animals take in oxygen and give off carbon dioxide. This delicate balance makes animals and plants dependent on each other for survival.



How Is ATP Formed?

Adenosine triphosphate, or ATP, is formed via photosynthesis and cellular respiration. ATP is the high-energy carrying molecule that drives vital biological functions for an organism to survive.

ATP is utilized by the cells in a variety of ways. It is mainly used in most animals for muscular contraction, protein synthesis and cognitive processes. Photosynthetic organisms, however, use ATP as a raw material to produce essential bio-molecules, such as glucose and oxygen.

Photosynthesis

Organisms that are capable of photosynthesis, including green plants and other autotrophs, create ATP from carbon dioxide, water and captured sunlight energy. This process involves two stages: light reactions and dark reactions. During the light reactions, the energy from the sun is converted into chemical energy in the form of ATP. Adenosine diphosphate, or ADP, undergoes photophosphorylation, where a phosphate group is added to it to form ATP molecules. Another product of the light reactions is NADPH. During the dark reactions, also referred to as the "Calvin cycle," the ATP and NADPH molecules are broken down to provide the energy required for the synthesis of glucose.

Cellular respiration

Animals rely on cellular respiration to produce usable energy. This set of metabolic pathways is driven by glucose, the primary organic product of photosynthesis. These pathways include glycolysis and aerobic respiration, further broken down into two: citric acid cycle and electron transport chain. Through a series of biochemical reactions coupled with enzymatic actions, glucose becomes completely oxidized at the end of cellular respiration to form 36 molecules of ATP.



What Is Responsible for Making ATP?

Adenosine triphosphate (ATP) is created in organisms through the processes of photosynthesis, glycolysis, cellular respiration and fermentation. Photosynthesis and fermentation are restricted to plants and fungi, respectively, but glycolysis and respiration occur in both plant and animal cells.

Photosynthesis is the process by which photons are filtered through chloroplasts in plant cells. This process creates ATP and electron carriers, which are then converted into carbohydrates such as glucose.

Glycolysis occurs either when a plant consumes its stored glucose or when the plant is consumed by another organism. Two ATP are created as a result of the breakdown of glucose into two pyruvate subunits. During cellular respiration, pyruvate is then combined with oxygen, creating carbon dioxide, water and 16 ATP per unit of pyruvate.

Fermentation converts pyruvate into ATP, carbon dioxide and ethanol. While not as efficient as other methods, fermentation is able to produce ATP in an anaerobic environment.



Why Is ATP Important in Cells?

Adenosine triphosphate, or ATP, is a molecule that stores all the energy required for cells to function. It is present in the nucleoplasm and cytoplasm of every cell. All of the energy needed to perform physiological operations is directly obtained from ATP.

An ATP molecule has three components: a sugar molecule center called ribose, a base of linked nitrogen and carbon atoms called adenine and a string of phosphate groups.

Energy is released from ATP molecules by a reaction that eliminates one of the phosphate-oxygen groups, leaving adenosine diphosphate, or ADP, behind. After an ATP molecule has been converted to ADP, the energy is spent.



What Is ATP Energy?

Energy that is produced in cells by a molecule called adenosine triphosphate is called ATP energy. ATP energy is essential for many living processes, including muscle contraction and nerve impulses. In order to provide continuous energy to cells, ATP molecules must have continuous access to foods that contain energy.

ATP is a molecule that generates energy by breaking down food in cells. Aside from muscle contraction, ATP is essential for creating nucleic acids in the body. Nucleic acids store DNA, and they are vital for healthy cell functioning.

The ATP molecule is made from a mixture of hydrogen, carbon, nitrogen, phosphorus and oxygen atoms. The bonds between some of these atoms contain large amounts of energy. When the bonds are broken, the excess energy is used to power the cell. Some of this energy can also sometimes be released as heat.

Once an ATP molecule has generated energy, it becomes adenosine diphosphate. In order to regenerate into ATP, the molecule uses fats and carbohydrates found in foods. The energy from the food recreates the bonds that were broken through a complex chemical process. This is why a constant supply of carbohydrates and fats is essential for a cell to survive.



What Makes Plant and Animal Cells Different?

There are several key differences between plant and animal cells, such as cell wall structure, presence or absence of plastids, lysosomes and centrioles and shape of vacuoles. These characteristics are the primary and most distinct differences between plant and animal cells. However, they only exist in organisms classified as eukaryotic, and occur primarily in central organelles

Cell wall structure varies considerably between plant and animal cells. In plant cells, walls have shape but lack a clearly defined and rigid structure; biologists refer to this as having nearly-present walls. Animal cells, on the other hand, have no cell walls present outside their cell membranes. In plant cells, plastids are located in the cytoplasm while animal cells lack plastids. Most animal cells contain lysosomes, which are located primarily in their cytoplasms. Plant cells do not typically have lysosomes; if they do, those structures are also located in their cytoplasms. Organelles called centrioles occur in some plant cells, but are only found in cells of lower plant varieties. Centrioles are found in all animal cells, however. The last primary difference between plant and animal cells is that all plant cells contain structures called vacuoles, which are filled with gel-like cell sap. Some animal cells contain vacuoles, too; if present, those vacuoles are temporary or small and contractile.



What Is the Purpose of Cell Division?

Cell division has three purposes for an organism: reproduction, growth and maintenance. For single-celled organisms, this is their direct and only method of reproduction, and it serves no other purpose. For multicellular organisms, cell division is a step in reproduction and is necessary for growth and maintenance.

Full Answer

Cell division occurs in two different basic ways. The first, and by far the most common, is mitosis. Mitosis is the only way in which single-celled organisms divide, and the vast majority of cell division for multicellular life is mitosis as well. In mitosis, a cell divides into two smaller cells, known as daughter cells, with identical genes. In single-celled organisms, these daughter cells generally have the same basic characteristics as the parent cell. In multicellular organisms, these can either be similar to the parent cell or, as in the case of the production of blood cells, very different, although the genes are the same.

Meiosis, on the other hand, produces gametes, daughter cells that are structurally different from their parent cells and contain only half the number of genes. Theses gametes are used for sexual reproduction in multicellular life and must combine with another corresponding gamete before they can begin growing via mitosis.



If a Human Skill Cell Has 46 Chromosomes, How Many Chromosomes Will Each New Skin Cell Have After Mitosis?

Human skin cells reproduce continuously, and each daughter cell carries a complete set of 46 chromosomes. Nucleated somatic cells, which make up the body and carry a complement of DNA, all have the same number of chromosomes as their parent cells.

The cells in the human body only undergo division when their DNA has been fully duplicated. Once the second string of DNA has been assembled, the cell divides into a pair of cells with roughly equal amounts of cytoplasm and organelles. This process leaves the cells of the body with full, identical complements of genes. Only germ-line cells undergo partial separation and carry 23 chromosomes.



Why Does a Cell Make a Copy of Its DNA Before Mitosis Occurs?

A cell makes a copy of its DNA before mitosis occurs so there is a set of DNA for the daughter cell after mitosis has occurred. Because each cell needs its own set of DNA, there must be two sets of DNA present in a cell before it divides into two.

Mitosis is the process of cell division that creates a new cell identical to the original. Somatic cells, such as muscles, hair and skin, undergo mitosis regularly in humans and other organisms. This is an important type of cell division needed to facilitate the repair of damaged cells, growth and replacement of old cells with new ones.

When a new cell is created, it must have the same library of genetic information all other cells in the body have access to. Because all the material in the new cell must come from the first cell, the original cell must make a copy of its DNA before completing the process of mitosis. These two sets of DNA only exist for as long as it takes the cell to undergo mitosis, which can be anywhere from 30 to 90 minutes in certain human cells. When the cell division is complete, both of the cells have a single identical copy of DNA.



What Is a Summary of Mitosis?

During mitosis, a cell enlarges, splits and multiplies DNA, and then separates into two daughter cells. During this reproductive cycle, the cell goes through five different phases

The five main phases of mitosis are prophase, prometaphase, metaphase, anaphase and telophase. Some mitosis timelines include interphase, where the cell begins preparing to undergo mitosis. Prophase is the official start of mitosis, and during this step duplicated DNA strands condense into a more compact form and take on the traditional X shape of chromosomes.

During prometaphase, the membrane around the cell's nucleus dissolves so that the chromosomes can move into place at the center of the cell. Spindle fibers align the chromosomes in the center of the nucleus during metaphase. This phase is essential to the health of the daughter cells, since it lines the chromosomes up evenly so they can be easily split in the next phase.

Anaphase is the phase where two different cells start truly forming. The chromosomes are pulled apart, and half of each chromosome is pulled to separate ends of the cell, creating two bundles of chromosomes.

In telophase, these bundles of chromosomes are enclosed in a new nuclear membrane. Once safely enclosed, the chromosomes break up again and lose their compact look. Finally, in cytokinesis the two sides break apart to create two new identical daughter cells.



What Is the Purpose of Cell Division?

Cell division has three purposes for an organism: reproduction, growth and maintenance. For single-celled organisms, this is their direct and only method of reproduction, and it serves no other purpose. For multicellular organisms, cell division is a step in reproduction and is necessary for growth and maintenance.

Cell division occurs in two different basic ways. The first, and by far the most common, is mitosis. Mitosis is the only way in which single-celled organisms divide, and the vast majority of cell division for multicellular life is mitosis as well. In mitosis, a cell divides into two smaller cells, known as daughter cells, with identical genes. In single-celled organisms, these daughter cells generally have the same basic characteristics as the parent cell. In multicellular organisms, these can either be similar to the parent cell or, as in the case of the production of blood cells, very different, although the genes are the same.

Meiosis, on the other hand, produces gametes, daughter cells that are structurally different from their parent cells and contain only half the number of genes. Theses gametes are used for sexual reproduction in multicellular life and must combine with another corresponding gamete before they can begin growing via mitosis.



DNA, Genes and Genomes

Deoxyribonucleic acid (DNA) is the chemical compound that contains the instructions needed to develop and direct the activities of nearly all living organisms. DNA molecules are made of two twisting, paired strands, often referred to as a double helix

Each DNA strand is made of four chemical units, called nucleotide bases, which comprise the genetic "alphabet." The bases are adenine (A), thymine (T), guanine (G), and cytosine (C). Bases on opposite strands pair specifically: an A always pairs with a T; a C always pairs with a G. The order of the As, Ts, Cs and Gs determines the meaning of the information encoded in that part of the DNA molecule just as the order of letters determines the meaning of a word.

An organism's complete set of DNA is called its genome. Virtually every single cell in the body contains a complete copy of the approximately 3 billion DNA base pairs, or letters, that make up the human genome.

With its four-letter language, DNA contains the information needed to build the entire human body. A gene traditionally refers to the unit of DNA that carries the instructions for making a specific protein or set of proteins. Each of the estimated 20,000 to 25,000 genes in the human genome codes for an average of three proteins.

Located on 23 pairs of chromosomes packed into the nucleus of a human cell, genes direct the production of proteins with the assistance of enzymes and messenger molecules. Specifically, an enzyme copies the information in a gene's DNA into a molecule called messenger ribonucleic acid (mRNA). The mRNA travels out of the nucleus and into the cell's cytoplasm, where the mRNA is read by a tiny molecular machine called a ribosome, and the information is used to link together small molecules called amino acids in the right order to form a specific protein.

Proteins make up body structures like organs and tissue, as well as control chemical reactions and carry signals between cells. If a cell's DNA is mutated, an abnormal protein may be produced, which can disrupt the body's usual processes and lead to a disease such as cancer.



DNA Sequencing

Sequencing simply means determining the exact order of the bases in a strand of DNA. Because bases exist as pairs, and the identity of one of the bases in the pair determines the other member of the pair, researchers do not have to report both bases of the pair.

In the most common type of sequencing used today, called sequencing by synthesis, DNA polymerase (the enzyme in cells that synthesizes DNA) is used to generate a new strand of DNA from a strand of interest. In the sequencing reaction, the enzyme incorporates into the new DNA strand individual nucleotides that have been chemically tagged with a fluorescent label. As this happens, the nucleotide is excited by a light source, and a fluorescent signal is emitted and detected. The signal is different depending on which of the four nucleotides was incorporated. This method can generate 'reads' of 125 nucleotides in a row and billions of reads at a time.

To assemble the sequence of all the bases in a large piece of DNA such as a gene, researchers need to read the sequence of overlapping segments. This allows the longer sequence to be assembled from shorter pieces, somewhat like putting together a linear jigsaw puzzle. In this process, each base has to be read not just once, but at least several times in the overlapping segments to ensure accuracy.

Researchers can use DNA sequencing to search for genetic variations and/or mutations that may play a role in the development or progression of a disease. The disease-causing change may be as small as the substitution, deletion, or addition of a single base pair or as large as a deletion of thousands of bases.



The Human Genome Project

The Human Genome Project, which was led at the National Institutes of Health (NIH) by the National Human Genome Research Institute, produced a very high-quality version of the human genome sequence that is freely available in public databases. That international project was successfully completed in April 2003, under budget and more than two years ahead of schedule.

The sequence is not that of one person, but is a composite derived from several individuals. Therefore, it is a "representative" or generic sequence. To ensure anonymity of the DNA donors, more blood samples (nearly 100) were collected from volunteers than were used, and no names were attached to the samples that were analyzed. Thus, not even the donors knew whether their samples were actually used.

The Human Genome Project was designed to generate a resource that could be used for a broad range of biomedical studies. One such use is to look for the genetic variations that increase risk of specific diseases, such as cancer, or to look for the type of genetic mutations frequently seen in cancerous cells. More research can then be done to fully understand how the genome functions and to discover the genetic basis for health and disease.



Implications of Genomics for Medical Science

Virtually every human ailment has some basis in our genes. Until recently, doctors were able to take the study of genes, or genetics, into consideration only in cases of birth defects and a limited set of other diseases. These were conditions, such as sickle cell anemia, which have very simple, predictable inheritance patterns because each is caused by a change in a single gene.

With the vast trove of data about human DNA generated by the Human Genome Project and other genomic research, scientists and clinicians have more powerful tools to study the role that multiple genetic factors acting together and with the environment play in much more complex diseases. These diseases, such as cancer, diabetes, and cardiovascular disease constitute the majority of health problems in the United States. Genome-based research is already enabling medical researchers to develop improved diagnostics, more effective therapeutic strategies, evidence-based approaches for demonstrating clinical efficacy, and better decision-making tools for patients and providers. Ultimately, it appears inevitable that treatments will be tailored to a patient's particular genomic makeup. Thus, the role of genetics in health care is starting to change profoundly and the first examples of the era of genomic medicine are upon us.

It is important to realize, however, that it often takes considerable time, effort, and funding to move discoveries from the scientific laboratory into the medical clinic. Most new drugs based on genome-based research are estimated to be at least 10 to 15 years away, though recent genome-driven efforts in lipid-lowering therapy have considerably shortened that interval. According to biotechnology experts, it usually takes more than a decade for a company to conduct the kinds of clinical studies needed to receive approval from the Food and Drug Administration.

Screening and diagnostic tests, however, are here. Rapid progress is also being made in the emerging field of pharmacogenomics, which involves using information about a patient's genetic make-up to better tailor drug therapy to their individual needs.

Clearly, genetics remains just one of several factors that contribute to people's risk of developing most common diseases. Diet, lifestyle, and environmental exposures also come into play for many conditions, including many types of cancer. Still, a deeper understanding of genetics will shed light on more than just hereditary risks by revealing the basic components of cells and, ultimately, explaining how all the various elements work together to affect the human body in both health and disease.


Great Value
Fast Delivery
Safe Payment
Shop Confidence
24/7 Help Center