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CSET Multiple Subjects: Subtest 2 -Science
CSET Multiple Subjects Subtest 2 Science
Planets - answer-Divided into two main types: large, low-density gas giants and smaller, rocky terrestrials -There are at least 341 identified planets, 8 of which are in the Solar System Solar System - answer-4 terrestrials: Mercury, Venus, Mars, Earth -4 gas giants: Jupiter, Saturn, Uranus, Neptune -At least 5 dwarf planets: Ceres, Pluto, Makemake, Haumea, Eris Venus - answer-Takes approx. seven and a half earth months for Venus to revolve around the sun -Takes approx. eight earth months to rotate on its axis -Therefore, a day on Venus is longer than a year -Similar in size to Earth -One of the few planets that rotate from east to west -Similar in size to Earth -Atmosphere is primarily composed of carbon dioxide -This thick atmosphere traps heat due to the greenhouse effect -The Magellan probe reached Venus in 1990 and provided detailed images of the planet Comet - answer-A small Solar System body that orbits the Sun
-When close enough to the sun, exhibits a visible coma (atmosphere) or a tail, both primarily from the effects of solar radiation upon the comet's nucleus -Comet nuclei are loose collections of ice, dust, and small rocky particles, measuring a few kilometers or tens of kilometers across -Have a variety of different orbital periods, ranging from a few years, to hundreds of thousands of years, while some are believed to pass through the inner Solar System only once before being thrown out into interstellar space Short-period comets - answerThought to originate in the Kuiper Belt, or associated scattered discs, which lie beyond the orbit of Neptune Long-period comets - answer-Believed to originate at a much greater distance from the Sun, in a cloud (the Oort cloud) consisting of debris left over from the condensation of solar nebula -Comets are thrown from the outer planets or nearby stars, or as a result of collisions Asteroids - answer-Sometimes called minor planets or planetoids -Bodies—primarily of the inner Solar System—that are smaller than planets but larger than meteoroids, excluding comets -The distinction between asteroids and comets is made by visual appearance; when discovered, comets show a perceptible coma while asteroids do not Earth - answer-Travels in an orbit that is slightly elliptical (oval), and so the distance from the sun ranges from 91.5 to 94.5 million miles -Its daily rotation deforms the earth to a flattened spheroid, with a polar radius slightly less than the equatorial radius Locations of the surface are described by a grid of latitude and longitude lines Gravity and inertia - answer-Both gravity and inertia work together to keep planets in orbit around the sun -Inertia makes a planet travel in a straight line -By definition, inertia is the tendency of a moving object to stay in a straight line or a stationary object to remain in place -However, the power of the sun's gravity pulls the planets toward the sun -The sun's gravity pulls the planets while their inertia keeps them moving forward in an elliptical orbit around the sun -The strength of gravity in our solar system depends on both the masses of the celestial objects and the distance between them -Gravity helps to explain the tides on earth -Without inertia, a planet would be pulled into the sun Weight and mass - answer-Gas giants Jupiter, Saturn, Uranus and Neptune have diameters far larger than Earth's and have far greater masses -An individual weighing 200 lbs on Earth would weigh more on a larger planet -Weight is a function of gravity
-Atmosphere is divided into the inner chromosphere with explosive prominences and the outer corona, a glowing halo visible only during a total eclipse -Constantly emitting particles as a solar wind Stars - answer-Bodies similar to the sun but immensely distant -Closest stars are 4 light-years away -Speed of light is 186,000 miles/second -Distance to closest stars can be calculated by measuring the parallax, a slight shift in apparent position against the background of more distant stars as the earth travels around the sun -Stars with the highest surface temperature appear blue, while stars with the lowest surface temperature appear red Galaxies - answer-Huge systems of stars -Milky Way is estimated to have 100 billion stars arranged in a great disk ---The sun is not at the center of the disk, but out toward the perimeter, and is revolving around the galactic center -Neighboring Andromeda galaxy is about 20 million light-years away -Galaxies of spiral, elliptical, and irregular form are speckled throughout the visible universe -Largest telescope has detected galaxies to its limit of several billion light-years The big bang theory of cosmology - answer-The spectra of distant objects display a red shift, which is interpreted as meaning that they are rapidly receding from us -This apparent expansion of the universe has given rise to the big bang theory of cosmology, in which one primeval mass exploded about 12 billion years ago Time zone - answer-A region of the earth that has uniform standard time, usually referred to as the local time -Time zones are divided into standard and daylight saving (or summer) -Daylight saving time zones (or summer time zones) include an offset (typically +1 hour) for daylight saving time -Standard time zones can be defined by geometrically subdividing the earth's spheroid into 24 lunes (wedge-shaped sections), bordered by meridians, each 15° of longitude apart -The local time in neighboring zones would differ by one hour -15° = 1 hour of time Seasons - answer-Result from the earth's axis being tilted to its orbital plane, NOT the result of the variation in the earth's distance to the sun (Because of its elliptical orbit, the earth as a whole is slightly warmer when away from the sun; this is because the Northern Hemisphere has more land than the Southern Hemisphere, and land warms more readily than sea) -Axis tilt deviates by an angle of approximately 23.5 degrees
-Thus, at any given time during summer or winter, one part of the planet is more directly exposed to the rays of the sun -This exposure alternates as the earth revolves in its orbit -At any given time, regardless of season, the Northern and Southern Hemispheres experience opposite seasons Seasonal weather differences between hemispheres - answer-Further caused by the elliptical orbit of the earth -Earth reaches perihelion (the point in its orbit closest to the sun) in January, and it reaches aphelion (farthest point from the sun) in July -Also depend on factors such as proximity to oceans or other large bodies of water, currents in those oceans, El Niño and other oceanic cycles, and prevailing winds Seasons in the temperate and polar regions - answer-Seasons are marked by changes in the amount of sunlight, which in turn often cause cycles of dormancy in plants and hibernation in animals -These effects vary with latitude and with proximity to bodies of water -For example, the South Pole is in the middle of the continent of Antarctica and is therefore a considerable distance from the moderating influence of the southern oceans -The North Pole is in the Arctic Ocean, and thus its temperature extremes are buffered by the water -The result is that the South Pole is consistently colder during the southern winter than the North Pole during the northern winter -The cycle of seasons in the polar and temperate zones of one hemisphere is opposite to that in the other; when it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere, and vice versa Equinoxes - answer-Occur twice a year, when the tilt of the earth's axis is oriented neither from nor to the sun, causing the sun to be located vertically above a point on the equator -The name derived from the Latin aequus (equal) and nox (night), because at the equinox, the night and day are equally long -Happen at two specific moments in time (not a whole day) around March 20 and Sept. 22 each year Winter solstice - answer-Occurs at the instant when the sun's position in the sky is at its greatest angular distance on the other side of the equatorial plane from the observer's hemisphere -Depending on the shift of the calendar, the winter solstice occurs some time between Dec. 20 and Dec. 23 each year in the Northern Hemisphere, and between June 20 and June 23 in the Southern Hemisphere, during either the shortest day or the longest night of the year Seasonal dates in the Northern Hemisphere - answer
-Temperature, pressure, and composition explain the three ways magma can form since they affect the melting point of rock -Igneous rock that cools beneath the earth's surface is called intrusive -Examples of intrusive rock formations include plutons, dikes, and batholiths -Igneous rock that forms on the earth's surface is called extrusive -Examples of extrusive rocks include obsidian, basalt, and pumice Metamorphic rocks - answer-Have undergone tremendous change from intense pressure and temperature -All examples of the rock cycle can change into metamorphic rock -Generally forms deep in the mantle as one type of rock changes into another -The mineral composition of the rock changes when the minerals in the rock recrystallize -Due to intense pressure, metamorphic rocks can show signs of bending and distortion -Examples of metamorphic rocks include schist, marble, gneiss, and slate -Usually classified according to texture and by chemical and mineral assemblage -Make up a large part of the earth's crust Coral reef - answerThe result of the buildup of once-living things Minerals - answer-Natural chemical compounds that are the crystals that make up rocks -Each mineral has a specific composition or narrow range of composition -The most abundant minerals in the crust are the two feldspars (orthoclase and plagioclase), quartz, olivine, and augite ---These five minerals are silicates, built from interlocking silicon and oxygen atoms Mineral hardness - answerA method one could use to determine the hardness of unknown mineral samples would be: -Scratch test: Test the item against materials of known hardness; for example, use your fingernail or the graphite in a pencil to attempt to scratch the items. This process should result in assigning a relative hardness to the unknown items. -Mohs' scale of hardness: This scale assigns a fixed number to 10 reference materials. Talc (1) is the softest and diamond (10) is the hardest -Cleavage: breaking along flat surfaces -Density: how much matter is in the object Mineral color - answerAffected by factors such as weathering and impurities Mountain - answer-A land form that stretches above the surrounding land in a limited area, with a peak -Usually produced by the movement of lithospheric plates -The compressional forces, isostatic uplift, and intrusion of igneous matter forces surface rock upward, creating a land form higher than the surrounding features -The height of the feature makes it either a hill or, if higher and steeper, a mountain
---A mountain is generally steeper than a hill, but there is no universally accepted standard definition for the height of a mountain or a hill, although a mountain usually has an identifiable summit -The major mountains tend to occur in long linear arcs, indicating tectonic plate boundaries and activity -Two types of mountains are formed, depending on how the rock reacts to the tectonic forces: block mountains or fold mountains -Some isolated mountains were produced by volcanoes, including many apparently small islands that reach a great height above the ocean floor River - answer-A natural flow of water, usually freshwater, traveling toward an ocean, a lake, or another stream -In some cases, a river flows into the ground or dries up completely before reaching another body of water -Usually larger streams are called rivers, while smaller streams are called creeks, brooks, rivulets, rills, and many other terms -A component of the water cycle Deserts - answer-Take up about 1/3 of the earth's land surface -Usually have a large diurnal (day) and seasonal temperature range, with high daytime temperatures, and low nighttime temperatures (due to extremely low humidity) -The temperature in the daytime can reach 45°C/113° or higher in the summer, and dip to 0°C/32° or lower in the winter -Water acts to trap infrared radiation from both the sun and the ground, and dry desert air is incapable of blocking sunlight during the day or trapping heat during the night -Thus, during daylight, most of the sun's heat reaches the ground and as soon as the sun sets, the desert cools quickly by radiating its heat into space -Many deserts are formed by rain shadows Rain shadow - answerMountains blocking the path of precipitation to the desert Weathering - answerThe process of chemical or physical breakdown of earth rocks, soils, and their minerals Mechanical/physical weathering - answerThe breakdown of rocks, soils and minerals through direct contact with atmospheric conditions such as heat, water, ice, and pressure Chemical weathering - answerThe breakdown of rocks, soils and minerals through atmospheric chemicals or biologically produced chemicals (also known as biological weathering) Soil - answer-The materials left over after the rock breaks down combine with organic material to create soil
-The earth is believed to be about 5.6 billion years old -The fossiliferous strata record is only the last 11% of the earth's history -Human civilization has lasted only 10,000 years -The immensity of geological time is the major discovery of geology -There has been ample time for very slow processes to produce large consequences The earth's structure - answerHas been inferred from its astronomical properties and seismic records of earthquake waves that have traveled through the interior of the earth -Center: 3000°C (temperature rises from the surface to the center) -Core: 31% of the earth's mass; iron and nickel metals, melted by the extremely high temperature of the center of the earth -Mantle: Largest zone of the planet (68%); crystalline silicates, rich in magnesium, calcium, and iron; very hot and mainly solid, but local melting to magma is the source of volcanic eruptions -Crust: Less than 1% of the earth; this relatively thin zone (5 to 25 miles) contains the only rocks we can study, even in the deepest mines or drill holes Crustal rocks - answer Earth movements - answer-The result of forces within the earth, where temperature and pressure differences lead to instability -The stress is particularly severe in orogenic zones, which are characterized by volcanism, metamorphism, deformation, and uplift ---Two styles of rock deformation are faulting and folding ---Edge-of-continent deformation is attributed to plate tectonics Plate tectonics - answer-Large-scale movements of the earth's lithosphere -The theory encompasses the older concepts of continental drift (first half of 20th century) and seafloor spreading (1960s) -The outermost part of the earth's interior is made up of two layers: the lithosphere and the asthenosphere -Lithosphere is comprised of the crust and the rigid uppermost part of the mantle -Lithosphere is broken up into tectonic plates (7 major and many minor) -The lithospheric plates ride on the asthenosphere
-Giant masses of solid rock that float upon the earth's mantle -These plates move in relation to one another at one of three types of plate boundaries: convergent/collision boundaries, divergent/spreading boundaries, and transform boundaries -Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along plate boundaries -The intensity of the earthquake depends on the type of tectonic motion that caused the initial earthquake -The lateral movement of the plates is typically at speeds of 50-100 mm annually
Continental drift - answer-Theory that the earth's continents were originally united as a supercontinent, Pangaea -Established by Alfred Wegener in the early 1900s Examples to support Wegener's theory: -Paleontology: Fossil evidence indicates the similarity of fossils on both sides of the Atlantic Ocean -Continental "jigsaw puzzle": The outlines of the continents seem to fit together—for example, the eastern coast of South America and the western coast of Africa -Paleoclimatology (study of ancient climates): Ancient coral reefs (associated with warm water) are found in areas that could not currently support such growth -Sea-floor spreading: ---The discovery of tectonic plate movement and sea-floor spreading provided proof for Wegner's theory ---The oceanic floor is not stationary ---The plates move because of incredible amounts of released energy ---During sea-floor spreading, new oceanic crust forms ---The Mid-Atlantic Ridge is an example ---In response to ocean-floor movement, the ocean floor expands in opposite directions ---Continents spread apart and away from the Mid-Atlantic Ridge Divergent plate movements - answer-Occur when two plates pull away from each other -Such faults are generally weak and shallow Example: the Mid-Atlantic Range in the Atlantic Ocean Convergent plate movements - answer-Occur when two plates push together -Such faults are strong and relatively deep -Where the strongest earthquakes occur Example: mountain building in the Himalayas and the Andes Transform plate movements - answer-Occur when two plates slip past each other -Such faults are generally moderate and are relatively shallow Example: The San Andreas Fault Pacific Ring of Fire - answer-An area of frequent earthquakes and volcanic eruptions associated with the plate boundaries surrounding the Pacific Ocean -In a 40,000 km horseshoe shape, it is associated with a nearly continuous series of oceanic trenches, volcanic arcs, and volcanic belts and/or plate movements -Accounts for the majority of earthquakes and volcanoes worldwide -Has 452 volcanoes and is home to over 75% of the world's active and dormant volcanoes
-On maps, the characteristics of an air mass are represented by two letters -The lowercase letter represents moisture, and the uppercase letter represents temperature -Maritime air forms over water and is associated with wet air -Continental air forms over land and is associated with dry air -Polar air forms south of the Arctic and is cold -Tropical air forms over the Tropics and is warm -mT = maritime tropical (wet, warm air) -mP = maritime polar (wet, cold air) -cT = continental tropical (dry, warm air) -cP = continental polar (dry, cold air) Hydrologic cycle - answer-Sun heats water in the oceans -Water evaporates as vapor into the air -Ice and snow can sublimate directly into water vapor -Evapotranspiration: water transpired from plants and evaporated from the soil -Rising air currents take the vapor up into the atmopshere where cooler temperatures cause it to condense into clouds -Air currents move clouds around the globe and cloud particles collide, grow, and fall out of the sky as precipitation -Some precipitation falls as snow and can accumulate as ice caps and glaciers, which can store water for thousands of years -Snow packs can thaw and melt, and the ensuing water flows overland as snowmelt -Most precipitation falls back into the oceans or onto land, where the precipitation flows over the ground as surface runoff -A portion of runoff enters rivers, with stream flow moving water towards the oceans -Runoff and groundwater are stored as freshwater in lakes -Not all runoff flows into rivers; much of it infiltrates into the ground through percolation -Some water infiltrates deep into the ground and replenishes aquifers, which store huge amounts of freshwater for long periods of time -Some infiltration stays close to the land surface and can seep back into surface-water bodies (and the ocean) as groundwater discharge -Some groundwater finds openings in the land surface and emerges as freshwater springs -Over time, the water reenters the ocean, where the water cycle started Hydrologic cycle (pic) - answer Hydrologic concepts - answer-Precipitation -Canopy interception -Snowmelt -Runoff -Percolation -Subsurface flow -Evaporation
-Sublimation -Condensation Precipitation - answer-Condensed water vapor that falls to the earth's surface -Most precipitation occurs as rain, but also includes snow, hail, fog drip, graupel, and sleet Canopy interception - answerThe precipitation that is intercepted by plant foliage and eventually evaporates back to the atmosphere rather than falling to the ground Snowmelt - answerThe runoff produced by melting snow Runoff - answer-The variety of ways by which water moves across the land -This includes both surface runoff and channel runoff -As it flows, the water may percolate into the ground, evaporate into the air, become stored in lakes or reservoirs, or be extracted for agricultural or other human uses Percolation - answerThe movement of rainwater as it filters through soil and rocks into the ground, becoming groundwater Subsurface flow - answer-The flow of water underground, in the vadose zone and aquifers -Subsurface water may return to the surface (as a spring or by being pumped) or eventually seep into the oceans -Water returns to the land surface at lower elevation than where it entered, under the force of gravity or gravity-induced pressures -Groundwater tends to move slowly and is replenished slowly, and so it can remain in aquifers for thousands of years Evaporation - answer-The transformation of water from liquid to gas phases as it moves from the ground or bodies of water into the overlying atmosphere -The source of energy for evaporation is primarily through solar radiation -Evaporation often implicitly includes transpiration from plants, although together they are specifically referred to as evapotranspiration Sublimation - answerThe state change where a solid (ice or snow) changes directly to a gas (water vapor) Condensation - answerThe transformation of water vapor to liquid water droplets in the air, producing clouds and fog Weather phenomena on earth - answer-Common: wind, clouds, rain, snow, fog, dust storms -Less common: natural disasters such as tornadoes, hurricanes, and ice storms
Differential heating - answer-The motive force behind land breezes and sea/lake breezes, also known as on- or off-shore winds -Land absorbs and radiates heat faster than water, but water releases heat over a longer period of time -The result is that, in locations where sea and land meet, heat absorbed over the day will be radiated more quickly by the land at night, cooling the air -Over the sea, heat is still being released into the air at night, and rises -This convective motion draws the cool land air in to replace the rising air, resulting in a land breeze in the late night and early morning -During the day, the roles are reversed -Warm air over the land rises, pulling cool air in from the sea to replace it, giving a sea breeze during the afternoon and evening Mountain breezes and valley breezes - answer-Due to a combination of differential heating and geometry -When the sun rises, it is the tops of the mountain peaks which receive first light, and as the day progresses, the mountain slopes take on a greater heat load than the valleys -This results in a temperature inequality between the two, and as warm air rises off the slopes, cool air moves up out of the valleys to replace it -This upslope wind is called a valley breeze -The opposite effect takes place in the afternoon, as the valley radiates heat -The peaks, long since cooled, transport air into the valley in a process that is partly gravitational and partly convective and is called a mountain breeze El Niño and La Niña - answer-Officially defined as sustained sea surface temperature anomalies of magnitude greater than 0.5°C across the central tropical Pacific Ocean -El Niño is characterized by unusually warm ocean temperatures in the eastern equatorial Pacific ---El Niño's warm current of nutrient-poor tropical water, heated by its eastward passage in the Equatorial Current, replaces the cold, nutrient-rich surface water of the Humboldt Current, also known as the Peru Current, which supports great populations of fish -La Niña is characterized by unusually warm ocean temperatures in the same area ---Atlanta tropical cyclone activity is generally enhanced during La Niña -The La Niña condition often follows the El Niño, especially when the latter is strong Climate - answer-Refers to the long-term weather patterns of a large geographical area and takes into account temperature, humidity, and precipitation -Latitude is the best determiner of climate, as it is consistently and directly correlated with temperature -The equator, at zero degrees latitude, generally has a tropical climate (warm and wet); at the extreme northern and southern latitudes (polar regions), the climate is very cold and dry -Rain shadows, as well as water currents, elevation and so forth, affect climate, but latitude is the primary factor
Estuary - answer-A semi-closed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea -Often associated with high levels of biological diversity -Typically the tidal mouths of rivers and are often characterized by sedimentation or silt carried in from terrestrial runoff, frequently from offshore -They are made up of brackish water -Often given names like bay, sound, fjord, etc.; the terms are not mutually exclusive -Ecosystems that are under threat from human activities such as pollution and overfishing World/global ocean - answer-Comprises one global, interconnected body of salt water often (though generally recognized as several separate oceans) -A continuous body of water with relatively free interchange among its parts -Major oceanic divisions are defined in part by the continents, various archipelagos, and other criteria: these divisions are (in descending order of size) the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Southern Ocean and the Arctic Ocean -Smaller regions of the oceans are called seas, gulfs, bays, and other names -Oceans cover 3/4 of the earth's surface -The evaporation of these oceans is how we get most of our rainfall, and their temperature determines our climate and wind patterns -Life within the ocean had already evolved 3 billion years prior to the movement of animal and plant life on land Surface ocean currents - answer-Classified as warm-water or cold-water currents -Surface ocean temperature is a major determiner of coastal climate -The Gulf-Stream is a warm-water current that carries warm water from the Tropics to the Arctic regions of the North Atlantic Ocean -This accounts for higher temperatures and higher humidity on the Eastern Seaboard during the summer -The cold-water current that flows north to south off the California coast keeps the West Coast fairly cool during the summer -Cold-water currents create cooler temperatures in areas that would otherwise be much warmer Tides - answer-The rising of the earth's ocean surface caused by the tidal forces of the moon and the sun acting on the oceans -Cause changes in the depth of the marine and estuarine water bodies and produce oscillating currents known as tidal streams, making prediction of tides important for coastal navigation -The changing tide produced at a given location is the result of the changing positions of the moon and sun relative to the earth, coupled with the effects of the earth's rotation and the bathymetry of oceans, seas, and estuaries -Sea level measured by coastal tide gauges may also be strongly affected by wind -Tides may be semidiurnal or diurnal -The tidal force produced by the sun is 46% as large as that produced by the moon
Parasites - answerPrey on other living organisms Saprophytes - answerExist on waste products and decaying organisms Algae - answer-Primitive plant group -Lack true roots, stems, and leaves -Range from a single cell to a huge seaweed -Mostly inhabit lakes and oceans Lichens - answerTwo organisms, a fungus and an alga, living together symbiotically Ferns - answerLack seeds and reproduce by means of spores, each of which may develop into a new plant without fertilization Gymnosperms - answerCone-bearing plants (including pines) with seeds exposed on cone scales Angiosperms - answerFlowering plants that bear their seeds within fruits Anaerobic organisms - answer-Exist without free oxygen -Include many yeasts and bacteria -For these organisms, in the process of fermentation, glucose is changed into ethonol and carbon dioxide anaerobically -All forms of life require water for biochemical reactions, reproduce by means of nucleic acid (DNA), and contain carbon atoms Ovule - answerSmall egg Ovule in seed plants - answer-In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells -After fertilization, the ovule develops into a seed Ovule in flowering plants - answer-In flowering plants, the ovule is located within the actual flower, the part of the carpel known as the ovary, which ultimately becomes the fruit -Depending on the plant, flowers may have one or multiple ovules per ovary -The ovule is attached to the placental wall of the ovary through a structure known as the funiculus (the plant equivalent of an umbilical cord) Photosynthesis - answer-A metabolic pathway that converts light energy into chemical energy -Plants use the energy in sunlight to convert carbon dioxide from the atmosphere, plus water, into simple sugars -These sugars are then used as building blocks and form the main structural component of the plant
-Thus, plants absorb carbon dioxide and give off oxygen Chlorophyll - answer-A green-colored, magnesium-containing pigment that is essential to the photosynthesis process -It is generally present in plant leaves and often in other plant parts as well Krebs cycle - answer-The sugar made by plants can be oxidized later in a process that releases energy -The oxidation can be in the plant itself or in an animal that eats the plant -The release of energy by oxidation of sugar is respiration Cell - answer-The smallest amount of living matter, a bit of organic material that is the unit of structure and function for all organisms -Range in size from the smallest speck visible through an electron microscope to the yolk of the largest egg -Some tiny organisms like bacteria are one celled, but all larger organisms are composed of many cells arrayed in tissues -Although an isolated cell may be spherical, the cells packed together in plant or animal tissue have flattened walls -The essential subdivisions of a cell are the cell membrane, the cytoplasm, and the cell nucleus Cell membrane - answerSemi-permeable, allowing some substances to pass while excluding others Cytoplasm - answer-The main material within a cell -Varies in consistency from a fluid to a semisolid -Embedded in the cytoplasm are functional bodies: ---The centrosome (participates in cell division) ---Ribosomes (for constructing proteins) ---Mitochondria (conduct metabolism) ---Golgi bodies (involved in secretion) ---Vacuoles (used in digestion) ---Plastids (in plant cells, bodies with chlorophyll that carry out photosynthesis) Cell nucleus - answer-A membrane-enclosed organelle found in all eukaryotic cells -Contains most of a cell's genetic material, organized as multiple long and linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes -The genes within these chromosomes are the cell's nuclear genome -The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression Chloroplasts - answer-Organelles found in plant cells and eukaryotic algae that conduct photosynthesis
