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Grace Hopper (1906-1992): An American computer scientist and U.S. Navy rear admiral. She was a pioneer in computer programming and developed the first compiler for a computer programming language, laying the groundwork for cobol. Garrett Augustus Morgan Sr. (1877-1963): An African American inventor who patented the traffic signal and the safety hood, a precursor to the modern gas mask. Hedy Lamarr (1914-2000): An Austrian-American actress and inventor who co-invented an early technique for spread spectrum communications, a key to modern wifi and bluetooth technology. Otis Boykin (1920-1982): An African American inventor who patented over 25 electronic devices, including a control unit for the pacemaker that is widely used today. Stephanie Kwolek (1923-2014): An American chemist who invented the synthetic fiber Kevlar, which is used in bulletproof vests and other protective equipment. Gladys West (b. 1930): An African American mathematician who played a crucial role in the development of the GPS technology we use today. Shirley Ann Jackson (b. 1946): An African American physicist who was the first African American woman to receive a doctorate at MIT and her work laid the foundations for the touch-tone telephone, caller ID, and call waiting. Tu Youyou (b. 1930): A Chinese pharmaceutical chemist who discovered artemisinin, a drug therapy that has significantly reduced the mortality rates for malaria, for which she was awarded the Nobel Prize in Physiology or Medicine in 2015. Chien-Shiung Wu (1912-1997): A Chinese-American physicist who made significant contributions to the Manhattan Project and disproved the hypothetical law of conservation of parity, for which her male colleagues received the Nobel Prize (she did not). Mária Telkes (1900-1995): A Hungarian-American biophysicist and architect dubbed the "Sun Queen" for her pioneering work in solar energy, including the development of the first solar-powered house. Percy Lavon Julian (1899-1975): An African American chemist and pioneer in the chemical synthesis of medicinal drugs from plants. Charles Ginsburg (1925-1992): An American engineer who led the team that developed the first commercial videotape recorder. Philo Farnsworth (1906-1971): An American inventor who developed an electronic television system and made major contributions to early television technology. María Montoya Martínez (1887-1980): A Native American (Tewa) potter from San Ildefonso Pueblo, New Mexico, who helped revive the traditional black-on-black pottery style and is considered one of the most influential Pueblo potters of the 20th century. Satya Nadella (b. 1967): An Indian-American business executive who has been the chief executive officer of Microsoft since 2014, overseeing the company's transformation into a cloud computing powerhouse. Junko Tabei (1939-2016): A Japanese mountaineer who in 1975 became the first woman to reach the summit of Mount Everest, and the first woman to ascend the Seven Summits, climbing the highest peaks on each continent. Mildred Dresselhaus (1930-2017): An American physicist and engineer, known as the "Queen of Carbon Science," who made groundbreaking contributions to the study of carbon materials like graphite and carbon nanotubes. Ellen Ochoa (b. 1958): An American engineer and former astronaut. In 1993, she became the first Hispanic woman to go to space when she flew on the Space Shuttle Discovery. Françoise Barré-Sinoussi (b. 1947): A French virologist who co-discovered HIV as the cause of AIDS, for which she was awarded the Nobel Prize in Physiology or Medicine in 2008. Esther Lederberg (1922-2006): An American microbiologist who made significant contributions to genetics and microbiology, including the discovery of the bacterial virus lambda, but whose work was often overshadowed by her husband's Nobel Prize-winning accomplishments.
What does the National Youth Theatre do? The National Youth Theatre organizes lots of exciting events. In 2006, the organization celebrated its 50th birthday. On the 10th of September, 2006, the members of the National Youth Theatre performed a show in Trafalgar Square, London. The show was on the same date as the National Youth Theatre's first play, fifty years before. The show started at midday, with a parade through the city to Trafalgar Square. Then about 1,500 young actors filled the square with lots of colourful and exciting performances. The smaller performances lasted until 8pm and then there was a final, special performance with amazing music and lights. The show was a great success. In 2007, the NYT started a special season called Generation ID Season. The members of the NYT worked on plays, films and even computer programs to show what life is like for young people today. The NYT does not only perform plays in the UK. The organization often travels to major cities in other countries to perform. The NYT has been to New York, Moscow, Paris, Berlin, Madrid and to lots of places in Holland and Norway. In 2008, the National Youth Theatre travelled to China and 25 members of the organization sang the British National Anthem to an audience of 91,000 at the Beijing Olympics. People all around the world watched their performance on television. This was a special performance because London will be the next city to hold the Olympic Games. Members of the NYT also performed Shakespeare's play, The Merchant of Venice, in Beijing.
The plasma membrane (also called the cell membrane) has several functions. For example, it allows only certain molecules to enter or leave the cell. It separates internal metabolic reactions from the external environment. In addition, the plasma membrane allows the cell to excrete wastes and to interact with its environment. Membrane Lipids The plasma membrane, as well as the membranes of cell organelles, is made primarily of phospholipids. Phospholipids have a polar, hydrophilic (“water-loving”) phosphate head and two nonpolar, hydrophobic (“water-fearing”) fatty acid tails. Water molecules sur- round the plasma membrane. The phospholipids line up so that their heads point outward toward the water and their tails point inward, away from water. The result is a double layer called a phospholipid bilayer, as shown in Figure 4-10. The cell membranes of eukaryotes also contain lipids, called sterols, between the tails of the phospho- lipids. The major membrane sterol in animal cells is cholesterol. Sterols in the plasma membrane make the membrane more firm and prevent the membrane from freezing at low temperatures. SECTION 3 OBJECTIVES ● Describe the structure and function of a cell’s plasma membrane. ● Summarize the role of the nucleus. ● List the major organelles found in the cytosol, and describe their roles. ● Identify the characteristics of mitochondria. ● Describe the structure and function of the cytoskeleton. VOCABULARY phospholipid bilayer chromosome nuclear envelope nucleolus ribosome mitochondrion endoplasmic reticulum Golgi apparatus lysosome cytoskeleton microtubule microfilament cilium flagellum centriole Cell membranes are made of a phospholipid bilayer. Each phospholipid molecule has a polar “head” and a two-part nonpolar “tail.” FIGURE 4-10 Copyright © by Holt, Rinehart and Winston. All rights reserved. 78 CHAPTER 4 OUTSIDE OF CELL INSIDE OF CELL 1. Cell-surface marker: Glycoprotein that identifies cell type 3. Enzyme: Assists chemical reactions inside the cell 2. Receptor protein: Recognizes and binds to substances outside the cell 4. Transport protein: Helps substances move across cell membrane Carbohydrate portion Protein portion Phospholipid heads Phospholipid tails Phospholipid Cholesterol bilayer Membrane Proteins Plasma membranes often contain specific proteins embedded within the lipid bilayer. These proteins are called integral proteins. Figure 4-11 shows that some integral proteins, such as cell surface markers, emerge from only one side of the membrane. Others, such as receptor proteins and transport proteins, extend across the plasma membrane and are exposed to both the cell’s interior and exterior environments. Proteins that extend across the plasma membrane are able to detect environmental signals and transmit them to the inside of the cell. Peripheral proteins, such as the enzyme shown in Figure 4-11, lie on only one side of the membrane and are not embedded in it. As Figure 4-11 shows, integral proteins exposed to the cell’s external environment often have carbohydrates attached. These carbohydrates can act as labels on cell surfaces. Some labels help cells recognize each other and stick together. Viruses can use these labels as docks for entering and infecting cells. Integral proteins play important roles in actively transporting molecules into the cell. Some act as channels or pores that allow certain substances to pass. Other integral proteins bind to a mol- ecule on the outside of the cell and then transport it through the membrane. Still others act as sites where chemical messengers such as hormones can attach. Fluid Mosaic Model A cell’s plasma membrane is surprisingly dynamic. Scientists describe the cell membrane as a fluid mosaic. The fluid mosaic model states that the phospholipid bilayer behaves like a fluid more than it behaves like a solid. The membrane’s lipids and pro- teins can move laterally within the bilayer, like a boat on the ocean. As a result of such lateral movement, the pattern, or “mosaic,” of lipids and proteins in the cell membrane constantly changes.
Gever Tulley is a computer scientist from California. In 2005, he started a summer programme for children called Tinkering School. The idea was that children can learn important skills for life by building things together. Gever Tulley and his team help the children to think big and create plans for innovative things they want to build. Children have made fantastic things since the school started. They have built a rollercoaster. They have made a rope bridge from plastic shopping bags. They have made tree houses, wooden motorbikes and boats. At Tinkering School, children get all kinds of materials like wood, metal, plastic, nails and ropes. They get lots of real tools too, such as knives, hammers, screwdrivers and power drills. Some children have cut themselves when using a knife, or hurt their fingers when using a hammer. Tinkering School has been around for many years now, but nobody has ever suffered a serious injury in all those years. This is because there are strict health and safety regulations they must follow. The children always learn how to use the tools safely and they must wear the right clothing and protection at all times. Gever Tulley's ideas have worked very well. A lot of children have gone to his summer schools over the years. In 2011, Gever Tulley and a colleague decided to create a 'real' ! school, called Brightworks, in San Francisco. The school is very small-it only has 20 students aged 6 to 13. Brightworks is based on the same principles as Tinkering School. Since it started, Brightworks has been written about a lot. Most of those articles have been very positive. They have praised the quality of the school. They have found the children are more motivated than at many other schools. But since the beginning of the school there have also been critical voices. Some people have said that children are not learning enough at Brightworks. They feel that students and teachers are just 'playing around' all the time. The students at Brightworks seem to love their school. We spoke to 12-year-old Tina Cooper. She has been a student at the school since last October. 'Since I started here, I've never sat in a 'normal' class with a teacher,' she told us. 'But it's been a very exciting experience. I've worked hard at my new school for eight months now, and there hasn't been one single moment when I found it boring. Before, I was bored quite often.'
LESSON 4. Cellular Respiration • Define cellular respiration • Identify the stages of clan respiration You have just learned how the energy from the sun is captured, processed, and stored in the form of glucose. Cellular respiration, another important life process, is the means by which cells release the stored energy in glucose to make adenosine triphosphate (ATP). The primary goal of this life process is to convert stored energy into usable form, such as ATP, for the cells to carry out their functions. Cellular respiration involves several chemical reactions. The reactions can be summed up in the following equation: C6 H12 O6 + 602 ----- 6 CO₂ +6H₂O + ATP Glucose oxygen carbon dioxide water energy Aerobic respiration reactions, or cellular respiration that takes place in the presence of oxygen, can be grouped into three stages glycolysis, Krebs cycle, and electron transport chain (ETC). Stage 1: Glycolysis Glycolysis is the process that breaks down one molecule of 6-C glucose into 3-C pyruvates or pyruvic acids. It also releases four molecules of ATP. This process occurs in the cytoplasm of the cell. The following is the step-by-step process of glycolysis. Take note that several enzymes are involved in this process. 1. The first step of glycolysis requires energy. It can only proceed when the two ATP molecules donate energy to the glucose by transferring a phosphate group with the help of an enzyme, producing glucose 6-phosphate 2. Then, a specific enzyme promotes the rearrangement of the atoms, producing the fructose 6-phosphate. 3. The action of the enzyme in step 2 promotes the transfer of a phosphate group from another ATP molecule, forming fructose 1,6-bisphosphate. 4. The resulting fructose 1,6-bisphosphate molecules, with the help of another enzyme, splits into two molecules, each with three carbon backbones. These two sugars are dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. 5. Another important enzyme then rapidly interconverts the molecules of dihydro-xyacetone phosphate and glyceraldehyde 3-phosphate. This produces two molecules of glyceraldehyde 3-phosphate or 3-phosphoglyceraldehyde (PGAL) 6. The succeeding step involves another enzyme-mediated action. The hydrogen (H) from PGAL is transferred to the oxidizing agent, nicotinamide adenine dinucleotide (NAD), which forms NADH. A phosphate (P) is also added from the cytosol of the cell to oxidize the two molecules of PGAL, forming two 1.3-bisphosphoglycerate. 7. A phosphate (P) from 1,3-biphosphoglycerate is transferred to ADP to form ATP. This happens for each of the two 1,3-bisphosphoglycerate. resulting to a yield of two ATP and two 3-phosphoglycerate molecules. 8. A phosphate is transferred from 3-phosphoglycerate molecules from the third carbon to the second carbon, forming 2-phosphoglycerate molecules A hydrogen atom and a hydroxyl ((OH) group is released, which then combines to form water (H2O). The removal of H2O from 2-phosphoglycerate results in the formation of 2- phosphoglycerate molecules. 9. A hydrogen atom and a hydroxyl ((OH) group is released, which then combines to form water (H2O). The removal of H2O from 2-phosphoglycerate results in the formation of two phosphoenolpyruvic acid (PEP) 10. Phosphate (P) from PEP is transferred to ADP (and forms ATP) and the final product, pyruvic acid. This reaction yields two molecules of pyruvic acid and two ATP molecules In summary, a single glucose molecule that undergoes the process of glycolysis produces two molecules of pyruvic acid, four molecules of ATP, two molecules of NADEL and two molecules of H.O. However, only two molecules of ATP are counted as net products since two molecules of ATP are spent throughout the process. Stage II: Krebs Cycle The Krebs cycle, named after its proponent Sir Hans Adolf Krebs, is a cyclical series of enzyme-controlled reactions. This stage of cellular respiration occurs in the matrix of the mitochondria. It is sometimes. called the citric acid cycle (CAC) since it produces citric acid. Citric acid contains three carboxyl (COOH) groups; hence, it is also called the tricarboxylic acid cycle (TCA). This requires the pyruvic acids produced during glycolysis. The main function of this cycle is to produce high-energy-yielding molecules, namely, NADH and flavin adenine dinucleotide (FADH) that will later on be used in the electron transport chain reaction. Figure 6-7. Summary of glycolysis and corresponding products in each reaction presented (See Appendix F on page 285 for an enlarged and complete version of the image.) An initial process is needed for the Krebs cycle to begin. As a pyruvate molecule from glycolysis enters the mitochondrion, it undergoes an important preliminary ate to form acetyl-CoA reaction. Coenzyme-A (COA) combines with pyruvate help of an enzymatic complex. This conversion also produces CO, and NADH. The Krebs cycle is summarized as follows. Take note that several enzymes are involved in this process. 1. The Krebs cycle technically begins when the acetyl-CoA combines with oxaloacetic acid (OAA), a 4-C molecule, to produce citric acid, a 6-C molecule. 2. With the aid of an enzyme, the citric acid now goes through a series of reactions that releases energy. Water molecule is removed from the citric acid and is returned in a different location. The-OH group is repositioned, forming the molecule isocitrate. 3. Isocitrate is then oxidized, forming the a-ketoglutarate, a 5-C molecule. The byproducts of this reaction are NADH and CO, 4 The a-ketoglutarate loses its CO, and a coenzyme-A is added in its place. The decarboxylation occurs with the help of NAD, which then becomes NADH. The resulting molecule is called succinyl-CoA. 5. Succinyl-CoA is converted into succinate. Also in this reaction, a molecule of guanosine triphosphate (GTP) is synthesized. The GTP molecule has similar structure and energy properties to that of ATP and is used by cells the same way. The free phosphate group attacks the succinyl-CoA molecule, which detaches the COA. Then, phosphate is attached to GDP to come up with GTP, similar to the process that occur in ATP synthesis (from ADP to ATP). 6. Two hydrogens are removed from succinate, A molecule of flavin adenine dinucleotide (FAD), a coenzyme similar to NAD, is reduced to FADH, as it takes the hydrogens from the succinate. This reaction produces the fumarate. 7. Fumarate is then converted into malate as the addition of a water molecule is catalyzed. The final reaction is the regeneration of oxaloacetate. The resulting byproduct of this regeneration is NADH Recall that two pyruvate molecules were produced during glycolysis, causing the Krebs cycle to turn twice. Each tuts produces three molecules of NADH, single ATH one FADIH, and the by-product CO, which is exhaled. Stage III: Electron Transport Chain The electron transport chain (ETC) is a series of photon pumps on the inner membrane of the mitochondrion. Electron transport is the last stage of the cellular respiration. In this stage, the energy from NADH and FADH, from the Krebs cycle is transferred to ADP to produce ATP. This process is generally known as oxidative phosphorylation. This energy coupling mechanism in the cell was revealed by the work of Peter stored energy in the form of proton (1) gradient to phosphorylate (add phosphate) ADP and produce ATP. The pumping of hydrogen sons across the inner membrane creates higher concentration ions in the inner membrane than on the outside of the membrane. This chemiosmotic gradient causes the ions to flow back across the membrane where the concentration of ions is lower. ATP synthase lined in the matrix serve as a channel protein, helping the ions to move across the membrane. The chemiosmotic gradient powers the phosphorylation of ADP to ATP, which also occurs in the ATP synthase. After passing through the ETC, the oxygen, being the final hydrogen acceptor, combines with two electrons and two protons, forming a water molecule. Water is a by-product of cellular respiration and is excreted. MINI TEST 6-3 1. Which energy-releasing pathway yields the most ATF in each glucose molecule? 2. Briefly describe the two stages of aerobic respiration that follow glycolysis: (a) Krebs cycle (b) Electron transport chain Anaerobic Respiration Most cells carry out arrobic respiration when oxygen is present. Aerobic respiration is an efficient process that yields a lot of ATP. However, many organisms thrive in mud, marshes, animal gut, canned goods, sewage treatment pond, and deep oceans where oxygen is scarce. Organisms that can live without oxygen are called anaerobes. Cellular respiration that proceeds without the presence of oxygen is called anaerobic respiration. In the event that the oxygen supply becomes low, aerobic cells also perform fermentation and lactic acid fermentation anaerobic pathways. There are two common anaerobic pathways in these cells, alcoholic fermentation and lactic acid fermentation. In alcoholic fermentation, ethyl alcohol and carbon dioxide are produced by some cells using the pyruvate from glycolysis. Each pyruvate molecule is rearranged into acetaldehyde and carbon dioxide, which is eventually released. NADII gives up electrons to acetaldehyde to form ethanol Fermentation is widely used in the industry. Yeast, a fungus used in making bread. can undergo anaerobic respiration. Bakers aux sugar, flour, water, and yeast to form the bread dough. The dough rises due to the carbon dioxide and alcohol released by the yeast cells trapped in air bubbles. Beer and wine manufacturers, we yeast to ferment the sugars in wheat and grape juice, forming alcoholic beverages such as beer and wine. In some cells, glycolysis produces two pyruvates, two NADH molecules, and two ATP molecules. Pyruvate itself becomes the final acceptor of the electrons from the NADH that produces the final product: lactate. Oftentimes, this product is called lactic acid. Human skeletal muscles can carry out fermentation when the blood cannot supply the cells with adequate oxygen during strenuous activities. When lactic acid builds up in the muscles, fatigue, burning sensation, and cramps result. Lactic acid will continue to build up until there is adequate supply of oxygen. Lactic acid is then converted back into pyruvate in the liver. Muscles also restore normal functions. Have you ever wondered why milk or cream turns sour after some time? Bacterial cells that undergo fermentation are responsible in producing lactate that turns the milk sour. These bacteria are used in manufacturing yogurt and sour milk products. Fermentation pathways do not breakdown and utilize the glucose completely. ATP is no longer produced beyond the process of glycolysis. Thus, energy produced is just enough for some single-celled organisms, or the energy can only be used by multicellular organisms for a short period.
CONCEPT OF INTEGERS What are INTEGERS? Integers are whole numbers that describe opposite ideas in mathematics. Integers can either be negative (-), positive (+) or zero. The integer zero is neutral. It is neither positive nor negative, but is an integer. Integers can be represented on a number line, which can help us understand the value of the integer. POSITIVE INTEGERS Are numbers to the right of zero. Are valued greater than zero. Express ideas of up, a gain or a profit. The sign for a positive integer is (+), however the sign is not always needed. Meaning +3 is the same value as 3. NEGATIVE INTEGERS Are numbers to the left of zero. Are valued less than zero. Express ideas of down or a loss. The sign for a negative integer is (-). This sign is always needed. Opposite Numbers/Integers – are the pairs of integers that have the same absolute value or have the same distance away from zero. ABSOLUTE VALUE The distance of a number from the origin (0) regardless of direction is called absolute value. The absolute value of a number is never negative. The symbol for absolute value is two straight lines surrounding the number or expression for which you wish to indicate absolute value. Examples: I 4 I = 4, +4 is read “ the absolute value of 4 is 4 “ I -3 I = 3, -3 is read “ the absolute value of -3 is 3” - I 3 I = -3, means “ the negative of the absolute value of 3 is -3 “ COMPARING AND ARRANGING INTEGERS Integers can be compared using a number line. As you move to the left along the number line, the integers decrease in value. On the other hand, integers increase in value as you move to the right along the number line. To arrange integers in ascending order is to arrange them from least to greatest. This means that when you use the number line, the smallest the integer is to the left of 0 on the number line. To arrange integers in descending order is to arrange them from greatest to least. This means that when you use the number line, the largest the integer is to the right of 0 on the number line. This is read as “nine is greater than negative 12.” This is read as “negative thirteen is less than negative 5.” This is read as “negative eight is greater than negative 18.”
What are INTEGERS? Integers are whole numbers that describe opposite ideas in mathematics. Integers can either be negative (-), positive (+) or zero. The integer zero is neutral. It is neither positive nor negative, but is an integer. Integers can be represented on a number line, which can help us understand the value of the integer. POSITIVE INTEGERS Are numbers to the right of zero. Are valued greater than zero. Express ideas of up, a gain or a profit. The sign for a positive integer is (+), however the sign is not always needed. Meaning +3 is the same value as 3. NEGATIVE INTEGERS Are numbers to the left of zero. Are valued less than zero. Express ideas of down or a loss. The sign for a negative integer is (-). This sign is always needed. Opposite Numbers/Integers – are the pairs of integers that have the same absolute value or have the same distance away from zero. ABSOLUTE VALUE The distance of a number from the origin (0) regardless of direction is called absolute value. The absolute value of a number is never negative. The symbol for absolute value is two straight lines surrounding the number or expression for which you wish to indicate absolute value. Examples: I 4 I = 4, +4 is read “ the absolute value of 4 is 4 “ I -3 I = 3, -3 is read “ the absolute value of -3 is 3” - I 3 I = -3, means “ the negative of the absolute value of 3 is -3 “ COMPARING AND ARRANGING INTEGERS Integers can be compared using a number line. As you move to the left along the number line, the integers decrease in value. On the other hand, integers increase in value as you move to the right along the number line. To arrange integers in ascending order is to arrange them from least to greatest. This means that when you use the number line, the smallest the integer is to the left of 0 on the number line. To arrange integers in descending order is to arrange them from greatest to least. This means that when you use the number line, the largest the integer is to the right of 0 on the number line. This is read as “nine is greater than negative 12.” This is read as “negative thirteen is less than negative 5.” This is read as “negative eight is greater than negative 18.” R
Ostinato Music Definition Ostinato (plural – ostinati or ostinatos) is an Italian word meaning obstinate or persistent and is used in music to describe a musical phrase or rhythm that is repeated persistently. The repeated pattern could be a melody, a figure in the bass – called a basso ostinato or simply a repeated rhythmic idea. An ostinato may be played for an entire piece of music or just during one section. The key aspect to remember in the definition of an ostinato is that it is a pattern that is repeated persistently in a piece of music. Rhythmic Ostinato A rhythmic ostinato is a rhythmic pattern that is persistently repeated. It will often be played on an untuned percussion instrument (e.g. snare drum, triangle, etc..). However, rhythmic ostinati can also be found in parts played on pitched instruments where the note pitch stays the same or where the pitches change as the phrase is repeated. The key characteristic is that it is the rhythm that is persistently repeated.In Maurice Ravel’s “Bolero” the use of a rhythmic ostinato brings a magical and almost hypnotic feel to the piece as the percussive pattern contrasts with the sweeping and almost improvisatory nature of the flute melody. Have a look at the pattern below and listen to its use in the audio extract: Rhythmic Ostinato Example from Ravel Bolero.A rhythmic ostinato is an excellent technique that composers use for creating drama and tension. One of the most famous examples of this is from “Mars” by Gustav Holst. Have a look/listen to the rhythmic pattern: Rhythmic Ostinato Example from Gustav Holst Mars. This rhythmic pattern is played relentlessly throughout the piece and forms the basis for the intense drama associated with the subject – Mars, the god of war! Have a listen to this extract of the piece performed by the United States Air Force Band:You can hear how the relentless sound of a rhythmic ostinato is extremely effective at building tension as the music around it changes and develops. This effect is heightened in the extract from Mars as the bass note remains on a G throughout the extract and acts as a pedal point. Not surprisingly, rhythmic ostinati are used widely in dramatic film music. Hans Zimmer is a film composer who makes considerable use of this technique across the many film scores he has written. Have a listen to the opening from his theme for the film “Pirates of the Caribbean” performed by the Auckland Symphony Orchestra:You can hear that there are a number of different ostinati in many of the different parts that are layered to produce the overall sound. Here is the rhythmic ostinato that forms the basis of the melody line: Rhythmic Ostinato Example Hans ZimmerMelodic ostinato A melodic ostinato is a repeated pattern where both the rhythm and the melody form the basis for the repeated pattern. These often occur in the bass part where they are called a basso ostinato. Basso Ostinato A basso ostinato is a repeated pattern in the bass part of a piece. This technique became particularly popular in the 17th century where a number of Baroque dances were based upon ostinati in the bass part. In dances such as the passacaglia the bass remained constant throughout the piece whilst the other parts developed. This technique is called “ground bass” and you can have a look at my lesson on ground bass for some examples of this. The most famous example of a basso ostinato is Pachelbel’s Canon in D. Ostinati Examples in Contemporary Music Rhythmic and melodic ostinatos have had a massive influence on contemporary popular music across a wide range of genres. This can be seen in 2 main ways: Riffs (short melodic phrases) – these are effectively contemporary expressions of ostinato. Loops – rhythmic and melodic phrases are repeated to create the characteristic sound of contemporary productions. As a result, you will probably be able to find examples of the use of repeated patterns/ostinati in most contemporary songs. However, there are some songs where the use of an ostinato provides the clear foundation for the song and these are useful examples to listen to. Examples of Ostinati Riffs Seven Nation Army by White Stripes The guitar riff from Seven Nation Army is one of the most famous modern guitar riffs and is used as an ostinato that plays throughout the song. It is an excellent example of a melodic ostinato:Back in Black by AC/DC The opening guitar riff in this song is another great example:Examples of Loops Loops are repeated patterns that are clearly built on the concept of ostinati. They are used widely in contemporary music. Hip hop songs often use loops as the foundation for the track. Still D.R.E by Dr. Dre ft. Snoop Dogg In this song a piano loop plays throughout the whole track and forms the foundation of the song: