PROJECT DONE BY, PRATHAM . N .GORANI GRADE -7 GLOBAL COMPASS
Temperature• Temperature is a measure of the average Kinetic Energy of the particles in a substance. – KE is the energy of motion. – The higher the average Kinetic Energy, the faster the particles move – Temperature and Heat are NOT the same thing
What is temperature?It is a variable to measure “hot”and “cold”. It is a measure ofan internal kinetic energy
Temperature Scales• There are 3 Types of Celsius Fahrenheit Temperature Scales – Fahrenheit – Celsius – Kelvin
Fahrenheit Scale• Most commonly used in United States. (originated in Great Britain)• Non-metric system scale• Not usually used in science Gabriel Fahrenheit
How Fahrenheit Works• Water freezes at 32°F• Water boils at 212°F• Zero was based on the lowest they could get water to stay liquid at the time (with salt in it).• 100° was based on the highest it was believed humans could survive at the time
Celsius Scale• Based on Metric System Scale• Most used in the world, including Canada, Europe, and Asia Anders Celsius
How Celsius Works• Water freezes at 0°C• Water boils at 100°C• Absolute zero is -273°C
Kelvin Scale• Actual Metric System scale.• Most often used in Laboratory settings for calculation purposes.• There are no negative temperatures.• A change (Δ) of 1oC = 1 K. William Thomson Baron of Kelvin
Absolute Zero• Defined as 0 Kelvin.• Average temperature of space is 2.7K• Scientists have gotten within fractions of absolute zero, but it is impossible to ever completely stop the movement of an atom, since that means it has zero energy. Boomerang Nebula contains theHelium can only become a gas at coldest known temperature in the below 5K universe at 1K
Temperature Scale Comparisons 373 K = 100°C 37°C = 99°F 298 K = 25°C 273 K = 0°C -40°C = -40°F 0 K = -273°C
What is heat?The flow of thermal energy fromone object to another.Heat always flows from warmer tocooler objectsIce gets warmer while hand getscoolerCup gets cooler while hand getswarmer
Heat TransferConduction, Convection, and Radiation
ConductionTakes place between solids or solids with liquids – Particles vibrating or moving faster transfer some of their energy to nearby atoms
Conduction When particles collide and the faster ones pass some of their energy on to the cooler ones. This results in a change in energy for each particleThis causes the fasterones to slow down andcoolThe slower ones speed upand heat up
Examples of ConductionConduction requires direct contact
Convection• Occurs in Fluids (liquids and gases)• Caused by a change in density due to a change in temperature.
Convection• The warmer fluid expands, becomes less dense and rises.• The cooler fluid contracts, becomes more dense and sinks.
ConvectionLava Lamps are an example of convection that you have probably seen before.
Importance of ConvectionConvection causes warm water vapor to rise, condense into clouds when it cools, and then falls back as rain Without convection, there would be no rainfall and thus no plants
Examples of Convection• Magma in the mantle rises due to convection.• The heat from the core heats it and then it rises to form volcanoes on the surface
Radiation• The transfer of energy due to Infrared and other electromagnetic rays.• Radiation can travel through space.• All things radiate heat.
Why are light bulbs hot?• They produce infrared radiation in addition to visible light• Infrared transfers energy to the molecules that makes them vibrate faster (thus hotter)
Thermal Expansion• When objects heat up their particles move faster, hit others harder, and bounce further, creating more empty space between the particles.• As a result, the entire substance expands.• This is known as thermal expansion
Examples of Thermal Expansion• Roads crack as they expand in the heat• On bridges and other sensitive sections, expansion panels allow it to flex.
Thermal Expansion• The liquid in a thermometer expands as it warms.• This causes it to head up the tube and tell you the temperature
Heat Transfer • Heat Conductors – Good thermal conductors transfer heat rapidly – Metals are good thermal conductorsRadiators are metals that transfer Frying pans transfer heat from the heat in the water to the air the stove to the food
Heat Transfer• Thermal Insulators – Poor thermal conductors of heat. – Asbestos, cork, ceramic, cardboard, and fiberglass are examples of thermal insulators
Expansion and contraction in solid , liquid , gas . The gas inside aSolids Liquids Gases balloon expands Mercury expands when heated. when heated.Expansionjoints expandwhen it is hot. WHAT HAPPENS WHEN WHAT HAPPENS WHEN RAILS CONTRACT? A GAS EXPANDS? The particles move more The particles are far apart The particles are not free freely than in solids. and move more freely than to move. Solids do not Liquids usually expand in liquids. Gases usually expand much. more than soilds. expand more than liquids.
Expansion and contraction in solids The gas inside a Solids Liquids Gases [close] balloon expands Mercury expands when heated.Expansion when heated.joints expandwhen it is hot. The rails cool. 0 10 The particles move more slowly and occupy less space. WHAT HAPPENS WHEN TheA GAS EXPANDS? volume decreases, and the rails contract. The particles move more The particles are far apart The particles are not free freely than in solids. and move more freely than to move. Solids do not Liquids usually expand in liquids. Gases usually expand much. 0more than soilds. 10 expand more than liquids.
Expansion and contraction The gas inside a Solids Liquids Gases balloon expands Mercury expands when heated.Expansion when heated.joints expandwhen it is hot. When gas expands, the volume increases. This can push a cork out. WHAT HAPPENS WHEN RAILS CONTRACT? The particles move more The particles are far apart The particles are not free freely than in solids. and move more freely than to move. Solids do not Liquids usually expand in liquids. Gases usually expand much. more than soilds. expand more than liquids.
Heat changes can be: endothermic Changes of state LIQUID exothermicWhen a stateof matter gainsor loses heat,it undergoesa change. GAS SOLID
ConductionThis is the transfer ofheat in most solids. particles of a solid The kinetic energy of the particles increases. Heat is transferred by direct contact.
Conductors and insulators Conductors allow heat to move through them easily. air space metal corkInsulators do notallow heat to movethrough them easily. plastic air Double-glazed window
Convection gas particles This is the transfer of heat in liquids and gases. convection currentsliquid particles Heat is transferred by the movement of currents.
Radiation This is the transfer of heat by electromagnetic waves.radiationemitted by solarplants radiation Greenhouse No contact is necessary between the source and the heated substance.
ADAPTATION OFPLANTS ACCORDING TO THE TEMPARATURES
The Desert :The desert is very dry and often hot. Annual rainfall averages less than 10 inches per year, andcomes all at the same time. The rest of the year is very dry. There is a lot of direct sunlightshining on the plants. The soil is often sandy or rocky and unable to hold much water. Windsare often strong, and dry out plants. Plants are exposed to extreme temperatures and droughtconditions. Plants must cope with extensive water loss.Desert Plant Adaptations :•Some plants, called succulents, store water in their stems or leaves;•Some plants have no leaves or small seasonal leaves that only grow after it rains. The lack ofleaves helps reduce water loss during photosynthesis. Leafless plants conduct photosynthesis intheir green stems.•Long root systems spread out wide or go deep into the ground to absorb water;•Some plants have a short life cycle, germinating in response to rain, growing, flowering, anddying within one year.•Leaves with hair help shade the plant, reducing water loss. Other plants have leaves that turnthroughout the day to expose a minimum surface area to the heat.•Spines to discourage animals from eating plants for water;•Waxy coating on stems and leaves help reduce water loss.•Flowers that open at night lure pollinators who are more likely to be active during the coolernight.Slower growing requires less energy. The plants dont have to make as much food andtherefore do not lose as much water.
• This cactus displays This cactus displays This plant has a waxy several desert light-colored hair that coating on its leaves. adaptations: it has spines helps shade the plant. rather than leaves and it stores water in its stem.
The Temperate Grasslands :The temperate grasslands, also called prairie, feature hot summers and coldwinters. Rainfall is uncertain and drought is common. The temperate grasslandsusually receive about 10 to 30 inches of precipitation per year. The soil is extremelyrich in organic material due to the fact that the above-ground portions of grasses dieoff annually, enriching the soil. The area is well-suited to agriculture, and few originalprairies survive today.Temperate Grassland (Prairie) Plant Adaptations :•During a fire, while above-ground portions of grasses may perish, the root portionssurvive to sprout again•Some prairie trees have thick bark to resist fire•Prairie shrubs readily resprout after fire•Roots of prairie grasses extend deep into the ground to absorb as much moisture asthey can•Extensive root systems prevent grazing animals from pulling roots out of the ground•Prairie grasses have narrow leaves which lose less water than broad leaves•Grasses grow from near their base, not from tip, thus are not permanently damagedfrom grazing animals or fire•Many grasses take advantage of exposed, windy conditions and are wind pollinated•Soft stems enable prairie grasses to bend in the wind
Soft stems enable prairie grasses to Many grasses are wind pollinatedbend in the wind. Narrow leaves and are well-suited to the exposed,minimize water loss. windy conditions of the grasslands.
The Tropical Rainforest :The tropical rainforest is hot and it rains a lot, about 80 to 180 inches per year. This abundanceof water can cause problems such as promoting the growth of bacteria and fungi which could beharmful to plants. Heavy rainfall also increases the risk of flooding, soil erosion, and rapidleaching of nutrients from the soil (leaching occurs when the minerals and organic nutrients ofthe soil are "washed" out of the soil by rainfall as the water soaks into the ground). Plants growrapidly and quickly use up any organic material left from decomposing plants and animals. Thisresults is a soil that is poor. The tropical rainforest is very thick, and not much sunlight is able topenetrate to the forest floor. However, the plants at the top of the rainforest in the canopy,must be able to survive 12 hours of intense sunlight every day of the year. There is a greatamount of diversity in plant species in the tropical rainforest.Tropical Rainforest Plant Adaptations :•Drip tips and waxy surfaces allow water to run off, to discourage growth of bacteria and fungi•Buttresses and prop and stilt roots help hold up plants in the shallow soil•Some plants climb on others to reach the sunlight•Flowers on the forest floor are designed to lure animal pollinators since there is relatively nowind on the forest floor to aid in pollination•Smooth bark and smooth or waxy flowers speed the run off of water•Plants have shallow roots to help capture nutrients from the top level of soil.•Many bromeliads are epiphytes (plants that live on other plants); instead of collecting waterwith roots they collect rainwater into a central reservoir from which they absorb the waterthrough hairs on their leaves•Epiphytic orchids have aerial roots that cling to the host plant, absorb minerals, and absorbwater from the atmosphere
Drip-tips on leaves help Prop roots help support Some plants collectshed excess water. plants in the shallow rainwater into a central soil. reservoir.
The Temperate Rain Forest :The temperate rain forest features minimal seasonal fluctuation oftemperature .The winters are mild and the summers cool. Thetemperate rain forest receives a lot of precipitation, about 80 to 152inches per year. Condensation from coastal fogs also add to thedampness. The soil is poor in nutrients. Large evergreen trees, somereaching 300 feet in height, are the dominant plant species.Temperate Rain Forest Plant Adaptations :•Epiphytes such as mosses and ferns grow atop other plants to reachlight.•Cool temperatures lead to slow decomposition but seedlings grow on"nurse logs" to take advantage of the nutrients from the decomposingfallen logs.•Trees can grow very tall due to amount of precipitation.
Epiphytes live on other plants to Trees can grow very tall in this veryreach the sunlight. moist environment.
The Temperate Deciduous Forest :There are four distinct seasons in the temperate deciduous forest: spring, summer, autumn, andwinter. The temperature varies from hot in the summer to below freezing in the winter. Rain isplentiful, about 30 to 50 inches per year. The temperate deciduous forest is made up of layersof plants; the number of layers depends upon factors such as climate, soil, and the age of theforest. The tallest trees make up the forest canopy which can be 100 feet or more above theground. Beneath the canopy, the understory contains smaller trees and young trees. Theseunderstory trees are more shade tolerant than canopy trees. Below the understory is a shrublayer. Carpeting the forest floor is the herb layer made up of wildflowers, mosses,andferns. Fallen leaves, twigs, and dried plants cover the ground, decompose, and help addnutrients to the topsoil.Temperate Deciduous Forest Plant Adaptations :•Wildflowers grow on forest floor early in the spring before trees leaf-out and shade the forestfloor•Many trees are deciduous (they drop their leaves in the autumn, and grow new ones inspring). Most deciduous trees have thin, broad, light-weight leaves that can capture a lot ofsunlight to make a lot of food for the tree in warm weather; when the weather gets cooler, thebroad leaves cause too much water loss and can be weighed down by too much snow, so thetree drops its leaves. New ones will grow in the spring.•Trees have thick bark to protect against cold winters.
Broad leaves can Many trees have thick In the autumn,capture a lot of sunlight bark to protect against deciduous trees dropfor a tree. the cold winters in the their leaves to minimize temperate deciduous water loss. forest.
The Taiga :Also know as boreal forests, the taiga is dominated by conifers (cone-bearing plants),most of which are evergreen (bear leaves thorughout the year). The taiga has coldwinters and warm summers. Some parts of the taiga have a permanently frozensublayer of soil called permafrost. Drainage is poor due to the permafrost or due tolayers of rock just below the soil surface, and together with the ground carved out byreceding glaciers, lead to the development of lakes, swamps, and bogs. The taigareceives about 20 inches of precipitation per year. The soil is acidic and mineral-poor. It is covered by a deep layer of partially-decomposed conifer needles.Taiga Plant Adaptations :•Many trees are evergreen so that plants can photosynthesize right away whentemperatures rise•Many trees have needle-like leaves which shape loses less water and sheds snowmore easily than broad leaves•Waxy coating on needles prevent evaporation•Needles are dark in color allowing more solar heat to be absorbed•Many trees have branches that droop downward to help shed excess snow to keepthe branches from breaking
Needle-like leaves help reduce The shape of many conifer treeswater loss and aids in the shedding helps shed heavy snow to saveof snow. branches from breaking.
The Tundra :The tundra is cold year-round—it has short cool summers and long, severewinters. The tundra has a permanently frozen sublayer of soil calledpermafrost. Drainage is poor due to the permafrost and because of the cold,evaporation is slow. The tundra receives little precipitation, about 4 to 10 inches peryear, and what it does receive is usually in the form of snow or ice. It has long daysduring the growing season, sometimes with 24 hours of daylight, and long nightsduring the winter. There is little diversity of species. Plant life is dominated bymosses, grasses, and sedges.Tundra Plant Adaptations :•Tundra plants are small (usually less than 12 inches tall) and low-growing due to lackof nutrients, because being close to the ground helps keep the plants from freezing,and because the roots cannot penetrate the permafrost.•Plants are dark in color—some are even red—this helps them absorb solar heat.•Some plants are covered with hair which helps keep them warm.•Some plants grow in clumps to protect one another from the wind and cold.•Some plants have dish-like flowers that follow the sun, focusing more solar heat onthe center of the flower, helping the plant stay warm.
This plant grows in a These tundra plants areclump to help conserve low-growing. heat.
Plant Adaptations in Water :•Underwater leaves and stems are flexible to move with water currents•Some plants have air spaces in their stems to help hold the plant up inthe water•Submerged plants lack strong water transport system (in stems);instead water, nutrients, and dissolved gases are absorbed through theleaves directly from the water.•Roots and root hairs reduced or absent; roots only needed foranchorage, not for absorption of nutrients and water•Some plants have leaves that float atop the water, exposing themselvesto the sunlight•In floating plants chlorophyll is restricted to upper surface of leaves(part that the sunlight will hit) and the upper surface is waxy to repelwater•Some plants produce seeds that can float
In floating plants, chlorophyll is Aquatic plants must be flexible torestricted to the upper surface. Note the withstand the pressures of movinggreen colour on the top of the leaves and water.the reddish underside of the overturned
ADAPTATION IN ANIMALS ACCORDING TO THE TEMPRATURE
Adaptations to colder climatesInsulation – refers to a material that does notconduct heat well. Examples: Birds – feathers Whales – blubber Some mammals - fur
Adaptations to Hot ClimatesAnimals must be able to get rid of excess heat.In desserts we can found: Fennec – have huge ears that provide a large surface area from which heat can escape. Camels – Their humps are made of fat, so they can live off this stored fat when food is scarce. *Other animals dig themselves to escape the heat of summer or the cold winter in the dessert.
Behaviors and MigrationAnimals can respond by instinct or with thehelp of a learned behavior.An instinct… is an inherited behavior that isdone automatically. An instinct can not be learned. Examples: Feed, built nests, attract mates, defend themselves.
Learned behaviorEverything that we done because welearned it, observing or assisted bysomeone else.Examples : In humans In other animals: Share Hunting Be organize Cooperate
MigrationMeans to move from one place to another.Reasons: Availability of food Changes in climate Mating Give birth
MigrationMost birds and some insects migrate to warm climates during thefall season.At this time of the year the temperature drops and the food availableis reduced.