Is It Healthy word quiz

Word and meaning in Arabic questions about the text (the meaning of the word today ) :I Today, there are cooking classes in some schools. In cooking classes, pupils learn fun ways to use healthy foods, especially fruits and vegetables. The children like to eat the healthy things they cook. Experts say that parents should also teach their children to cook at home. II But not all parents think that teaching children to cook is a good idea. Dan worries about his children. "Sometimes cooking is dangerous for children," he says. "For example, children must boil water to cook pasta." His wife Nancy agrees with him about the danger. She also says, "When children cook at home, I have to clean the kitchen after they finish cooking." III It is true that there may be more work for the parents when children cook in the kitchen. But there will also be happy memories when parents and children cook together. Also, children enjoy making things, like a vegetable pie, for their family and friends. This makes them feel proud of themselves

The endoplasmic reticulum (EN-doh-PLAZ-mik ri-TIK-yuh-luhm), abbre- viated ER, is a system of membranous tubes and sacs, called cisternae (sis-TUHR-nee). The ER functions primarily as an intracellu- lar highway, a path along which molecules move from one part of the cell to another. The amount of ER inside a cell fluctuates, depending on the cell’s activity. There are two types of ER: rough and smooth. The two types of ER are thought to be continuous. Rough Endoplasmic Reticulum The rough endoplasmic reticulum is a system of interconnected, flattened sacs covered with ribosomes, as shown in Figure 4-15. The rough ER produces phospholipids and proteins. Certain types of proteins are made on the rough ER’s ribosomes. These proteins are later exported from the cell or inserted into one of the cell’s own membranes. For example, ribosomes on the rough ER make digestive enzymes, which accumulate inside the endoplasmic retic- ulum. Little sacs or vesicles then pinch off from the ends of the rough ER and store the digestive enzymes until they are released from the cell. Rough ER is most abundant in cells that produce large amounts of protein for export, such as cells in digestive glands and antibody-producing cells. Smooth Endoplasmic Reticulum The smooth ER lacks ribosomes and thus has a smooth appear- ance. Most cells contain very little smooth ER. Smooth ER builds lipids such as cholesterol. In the ovaries and testes, smooth ER produces the steroid hormones estrogen and testosterone. In skeletal and heart muscle cells, smooth ER releases calcium, which stimulates contraction. Smooth ER is also abundant in liver and kidney cells, where it helps detoxify drugs and poisons. Long-term abuse of alcohol and other drugs causes these cells to produce more smooth ER. Increased amounts of smooth ER in liver cells is one of the factors that can lead to drug tolerance. As Figure 4-15 shows, rough ER and smooth ER form an interconnected network. Copyright © by Holt, Rinehart and Winston. All rights reserved. reticulum from the Latin rete, meaning “net”; reticulum means “little net” Word Roots and Origins The endoplasmic reticulum (ER) serves as a site of synthesis for proteins, lipids, and other materials. The dark lines in the photo represent the membranes of the ER, and the narrow lighter areas between the dark lines show the channels and spaces (cisternae) inside the ER. FIGURE 4-15 Smooth ER Ribosomes Rough ER Cisternae 82 CHAPTER 4 GOLGI APPARATUS The Golgi apparatus, shown in Figure 4-16, is another system of flattened, membranous sacs. The sacs nearest the nucleus receive vesicles from the ER containing newly made proteins or lipids. Vesicles travel from one part of the Golgi apparatus to the next and transport substances as they go. The stacked membranes modify the vesicle contents as they move along. The proteins get “address labels” that direct them to various other parts of the cell. During this modification, the Golgi apparatus can add carbohydrate labels to proteins or alter new lipids in various ways. VESICLES Cells contain several types of vesicles, which perform various roles. Vesicles are small, spherically shaped sacs that are surrounded by a single membrane and that are classified by their contents. Vesicles often migrate to and merge with the plasma membrane. As they do, they release their contents to the outside of the cell. Lysosomes Lysosomes (LIE-suh-SOHMZ) are vesicles that bud from the Golgi appa- ratus and that contain digestive enzymes. These enzymes can break down large molecules, such as proteins, nucleic acids, car- bohydrates, and phospholipids. In the liver, lysosomes break down glycogen in order to release glucose into the bloodstream. Certain white blood cells use lysosomes to break down bacteria. Within a cell, lysosomes digest worn-out organelles in a process called autophagy (aw-TAHF-uh-jee). Lysosomes are also responsible for breaking down cells when it is time for the cells to die. The digestion of damaged or extra cells by the enzymes of their own lysosomes is called autolysis (aw-TAHL-uh-sis). Lysosomes play a very important role in maintaining an organism’s health by destroying cells that are no longer functioning properly. Copyright © by Holt, Rinehart and Winston. All rights reserved. The Golgi apparatus modifies many cellular products and prepares them for export. FIGURE 4-16 CELL STRUCTURE AND FUNCTION 83 Peroxisomes Peroxisomes are similar to lysosomes but contain different enzymes and are not produced by the Golgi apparatus. Peroxisomes are abundant in liver and kidney cells, where they neutralize free radicals (oxygen ions that can damage cells) and detoxify alcohol and other drugs. Peroxisomes are named for the hydrogen peroxide, H2O2, they produce when breaking down alco- hol and killing bacteria. Peroxisomes also break down fatty acids, which the mitochondria can then use as an energy source. Other Vesicles Specialized peroxisomes, called glyoxysomes, can be found in the seeds of some plants. They break down stored fats to provide energy for the developing plant embryo. Some cells engulf material by surrounding it with plasma membrane. The resulting pocket buds off to become a vesicle inside the cell. This vesicle is called an endosome. Lysosomes fuse with endosomes and digest the engulfed material. Food vacuoles are vesicles that store nutrients for a cell. Contractile vacuoles are vesicles that can contract and dispose of excess water inside a cell. Protein Synthesis One of the major functions of a cell is the production of protein. The path some proteins take from synthesis to export can be seen in Figure 4-17. In step , proteins are assembled by ribosomes on the rough ER. Then, in step , vesicles transport proteins to the Golgi apparatus. In step , the Golgi modifies proteins and pack- ages them in new vesicles. In step , vesicles release proteins that have destinations outside the cell. In step , vesicles containing enzymes remain inside the cell as lysosomes, peroxisomes, endo- somes, or other types of vesicles. 5 4 3 2 1 Copyright © by Holt, Rinehart and Winston. All rights reserved. Proteins are assembled by ribosomes on the rough ER. Vesicles carry proteins from the rough ER to the Golgi apparatus. Proteins are modified in the Golgi apparatus and enter new vesicles. Some vesicles release their proteins outside the cell. Other vesicles remain in the cell and become lysosomes and other vesicles. Nucleus

Key Word Definition Aid Assistance in the form of grants or loans at below market rates. For example, the UK provided aid to Nepal after the 2015 earthquake to help with reconstruction efforts. Barriers to Trade Government constraints on the flow of international goods and services, such as tariffs and quotas. For example, the European Union imposes tariffs on certain agricultural products to protect its farmers. BRICS An acronym for an association of five major emerging nations: Brazil, Russia, India, China, and South Africa. For example, BRICS nations often meet to discuss economic cooperation and development strategies. Demographic Aging The rise in the median age of a population. For example, Japan is experiencing demographic aging, with a significant increase in the elderly population. Economic Core Region The most highly developed region(s) in a country. For example, London is considered an economic core region in the UK due to its high level of development and economic activity. GNP (Gross National Product) GDP plus overseas earnings, also known as GNI (Gross National Income). For example, the GNP of the United States includes the value of goods and services produced domestically and the income earned by its citizens abroad. HIC (Higher Income Country) A country with a high level of income and development. For example, Germany is classified as a higher income country due to its high GDP per capita and advanced infrastructure. NEE (Newly Emerging Economy) A country that is experiencing rapid economic growth and industrialisation. For example, China is an example of a newly emerging economy, having rapidly industrialised and grown economically over the past few decades. LIC (Lower Income Country) A country with a low level of income and development. For example, Malawi is considered a lower income country, with a low GDP per capita and limited access to healthcare and education. GDHI (Gross Disposable Household Income) The amount of money that households have available for spending and saving after taxes and social contributions. For example, in the UK, the GDHI varies significantly between regions, with London having one of the highest levels. Gini Coefficient A measure of income inequality within a population, ranging from 0 (perfect equality) to 100 (perfect inequality). For example, South Africa has a high Gini coefficient, indicating significant income inequality within the country. Trade Unions Organisations that promote trade between member countries, such as the East African Community (EAC). For example, the East African Community (EAC) works to promote economic integration and trade among its member states. Fair Trade A movement aimed at helping producers in developing countries achieve better trading conditions and promote sustainability. For example, Fairtrade coffee ensures that farmers receive a fair price for their product and work under safe conditions. FDI (Foreign Direct Investment) Investment made by a company or individual in one country in business interests in another country. For example, Toyota's investment in manufacturing plants in the UK is an example of foreign direct investment. Debt Relief The partial or total remission of debts, especially those owed by developing countries to external creditors. For example, the Heavily Indebted Poor Countries (HIPC) initiative provides debt relief to eligible countries to help them achieve sustainable development. International Aid Voluntary transfer of resources from one country to another, often in the form of financial assistance, goods, or services. For example, the UK provides international aid to various countries through its Department for International Development (DFID). Top-Down Development Large-scale development projects led by national governments or international organisations. For example, the construction of the Three Gorges Dam in China is an example of a top-down development project. Bottom-Up Development Small-scale development projects led by local communities or NGOs, focusing on the needs of the poorest and most vulnerable. For example, WaterAid's installation of hand pumps in rural villages in Africa is an example of a bottom-up development project. Urbanisation The increase in the proportion of people living in urban areas compared to rural areas. For example, rapid urbanisation in India has led to the growth of megacities like Mumbai and Delhi. Geopolitics The study of the effects of geography (human and physical) on international politics and relations. For example, the geopolitics of the Arctic region involves disputes over territorial claims and access to natural resources. Quality of Life The general well-being of individuals and societies, outlining negative and positive features of life. For example, Scandinavian countries are often ranked high in quality of life due to their strong social welfare systems and high levels of happiness. Poverty Cycle A set of factors or events by which poverty, once started, is likely to continue unless there is outside intervention. For example, lack of education and healthcare can trap families in a poverty cycle, making it difficult for future generations to improve their living standards. Sustainable Development Economic development that is conducted without depletion of natural resources. For example, the use of renewable energy sources like wind and solar power is a key aspect of sustainable development. Humanitarian Aid Material or logistical assistance provided for humanitarian purposes, typically in response to crises including natural disasters and man-made disaster. For example, humanitarian aid was provided to Haiti after the devastating earthquake in 2010 to help with immediate relief efforts. Economic Growth An increase in the production of goods and services in an economy over a period of time. For example, China's economic growth over the past few decades has lifted millions of people out of poverty. Social Indicators Measures that describe the well-being of individuals or communities, such as health, education, and income. For example, life expectancy and literacy rates are common social indicators used to assess development. Environmental Sustainability Responsible interaction with the environment to avoid depletion or degradation of natural resources and allow for long-term environmental quality. For example, practices like recycling and conservation of natural habitats contribute to environmental sustainability. Infrastructure The basic physical and organisational structures and facilities needed for the operation of a society or enterprise. For example, good infrastructure, such as roads, bridges, and schools, is essential for economic development. Globalisation The process by which businesses or other organisations develop international influence or start operating on an international scale. For example, the globalisation of technology companies like Apple and Google has led to their products being available worldwide. Microfinance Financial services provided to low-income individuals or groups who are typically excluded from traditional banking. For example, microfinance institutions like Grameen Bank provide small loans to entrepreneurs in developing countries to help them start or expand their businesses.

A symbiosis (SIM-bie-OH-sis) is a close, long-term relationship between two organisms. Three examples of symbiotic relation- ships include: parasitism, mutualism, and commensalism. Parasitism (PAR-uh-SIET-IZ-UHM) is a relationship in which one indi- vidual is harmed while the other individual benefits. Mutualism (MYOO-choo-uhl-IZ-uhm) is a relationship in which both organisms derive some benefit. In commensalism (kuh-MEN-suhl-IZ-uhm), one organism benefits, but the other organism is neither helped nor harmed. Parasitism Parasitism is similar to predation in that one organism, called the host, is harmed and the other organism, called the parasite, benefits. However, unlike many forms of predation, parasitism usually does not result in the immediate death of the host. Generally, the parasite feeds on the host for a long time rather than kills it. Parasites such as aphids, lice, leeches, fleas, ticks, and mosquitoes that remain on the outside of their host are called ectoparasites. Parasites that live inside the host’s body are called endoparasites. Familiar endoparasites are heart- worms, disease-causing protists, and tapeworms, such as the one shown in Figure 20-5. Natural selection favors adaptations that allow a parasite to exploit its host efficiently. Parasites are usually specialized anatomically and physiologically for a par- asitic lifestyle. Parasites can have a strong negative impact on the health and reproduction of the host. Consequently, hosts have evolved a variety of defenses against parasites. Skin is an important defense that prevents most parasites from entering the body. Tears, saliva, and mucus defend openings through which parasites could pass, such as the eyes, mouth, and nose. Finally, the cells of the immune system may attack para- sites that get past these defenses. parasite from the Latin word parasitus, meaning “one who eats at the table of another” Word Roots and Origins Tapeworms are endoparasites that can grow to 20 m or greater in length. Tapeworms are so specialized for a parasitic lifestyle that they do not have a digestive system. They live in the host’s small intestine and absorb nutrients directly through their skin. Tapeworms reproduce by producing egg-filled chambers, which are released in their host’s feces to be unknowingly picked up by a future host. FIGURE 20-5 Copyright © by Holt, Rinehart and Winston. All rights reserved. 404 CHAPTER 20 Mutualism Mutualism is a relationship in which two species derive some benefit from each other. Some mutualistic relation- ships are so close that neither species can survive without the other. An example of mutualism, shown in Figure 20-6, involves ants and some species of Acacia plants. The ants nest inside the acacia’s large thorns and receive food from the acacia. In turn, the ants protect the acacia from herbi- vores and cut back competing vegetation. Pollination is one of the most important mutualistic rela- tionships on Earth. Animals such as bees, butterflies, flies, beetles, bats, and birds that carry pollen between flowering plants are called pollinators. A flower is a lure for pollina- tors, which are attracted by the flower’s color, pattern, shape, or scent. The plant usually provides food—in the form of nectar or pollen—for its pollinators. As a pollinator feeds in a flower, it picks up a load of pollen, which it may then carry to other flowers of the same species. Commensalism Commensalism is an interaction in which one species benefits and the other species is not affected. Species that scavenge for leftover food items are often considered commensal species. However, a relationship that appears to be commensalism may simply be mutu- alism in which the mutual benefits are not apparent. An example of a commensal relationship is the relationship between cattle egrets and Cape buffaloes in Tanzania. The birds feed on small animals such as insects and lizards that are forced out of their hiding places by the movement of the buffaloes through the grass. Occasionally, the cattle egrets also feed on ectoparasites from the hide of the buffaloes, but the buffaloes gen- erally do not benefit from the presence of the egrets.

Is It Healthy?

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