**Soil consists of living and nonliving materials. Thesematerials have three main components: broken downrocks and minerals, small organisms like insects,bacteria, and fungus, and dead plant and animalmaterial. It contains the nutrients and water thatplants need to live. The roots of plants absorb thenutrients and water in the soil that are trappedbetween the soil particles. Plants use the nutrientsand water, along with energy from the sun, to makefood and to grow. Soil also gives plant roots a place toanchor themselves so that the plant can stand uprightand grow. This support holds the plant in place evenduring wind and rain storms.
**Soil consists of living and nonliving materials.These materials have three main components:broken down rocks and minerals, smallorganisms like insects, bacteria, andfungus, and dead plant and animal material. Itcontains the nutrients and water that plantsneed to live.
**Abiotic factors:broken down rocks and minerals*Biotic factors (alive):small organisms like insects, bacteria, and fungus*Biotic factors (not alive):dead plant and animal material
**The roots of plants absorb the nutrients andwater in the soil that are trapped between thesoil particles.
**Plants use the nutrients and water, along withenergy from the sun, to make food and togrow.
**Soil also gives plant roots a place to anchorthemselves so that the plant can stand uprightand grow. This support holds the plant in placeeven during wind and rain storms.
**To help students understand soil and itsfunctions, have them collect samples of soil fromoutside their house. By using a hand lens ormagnifier, students can examine the soil andobserve the small particles. Also, students canexperiment by growing plants with or without soil.Have them plant a bean in a cup of soil and anotherbean in a wet paper towel. Water the soil andpaper towel when they become dry and observe thegrowth of the bean plants over several months.Both beans should sprout and become small plants..
BEANS SPROUTIN SOILOR ONWET PAPER TOWELIN THE SUNLIGHT
*After a period of time, students should observethat the bean plant in soil is thriving while theone in the paper towel is not. They mayconclude that the bean planted in the soil isgrowing because the soil offers the nutrientsand support that the bean needs.*
*A food chain is a diagram that shows how energyis passed from one living thing to another. Foodgives living things energy. Animals need to eatfood to get energy, while plants get energy fromthe food they make.
**Most food chains start with a plant. The following"link" in the chain would be an animal that eats thatplant, and the next "link" would be an animal that eatsthe previous animal. The arrows in a food chain showhow energy is passed between the "links" - not whichanimal hunts another animal. For example, a forestfood chain might look like this:Or, in the ocean, like this:algae fish sealGrass deer mountain lion
*Students should know that the theory of naturalselection was developed by Charles Darwin andbe able to explain his ideas on how organismschange over time to survive in a changingenvironment.
**The British scientist, Charles Darwin, argued that anorganism has a special trait, or characteristic, thathelps it survive, like blending into the surroundingsor the ability to run quickly to get away frompredators.*Because it survives, an organism is able toreproduce and pass on the traits that enabled it tosurvive to its offspring.*Darwin called this process natural selection.
If there is a species of varying brownish-white mice that live in theforest, the individuals that are mostly white will not survive as well asthe ones that are primarily brown. The mostly white ones will standout more in the dark forest and owls will hunt them more easily. Thismeans that the mostly brown mice will live to reproduce and thewhite ones will not. The offspring of these mostly brown mice will bemostly brown as well. Eventually, mostly brown mice will exist in thisforest and primarily white mice will become rare. The change in aspecies characteristics develop over very long periods of time becausethere are only slight changes in the organisms which must be passeddown through many generations.
**Fossils are hardened plant or animal remainsand prints from long ago. Scientists believethat fossils show that many species of livingthings have gradually changed over time, orhave become extinct, due to natural selection.
**When an organism becomes extinct, everymember of that particular type dies and thereare no more left on earth. If a species isunable to survive and produce moreoffspring, its numbers decrease, while aspecies better suited to the environmentsurvives to reproduce.
*NATURAL SELECTIONTo understand how Darwin applied the theory ofnatural selection, students can look at picturesof animals and different environments anddiscuss which would survive the best in eachenvironment. They can also discuss what wouldhappen to animals that are not well suited totheir environment.
*An adaptation is a unique trait, orcharacteristic, that an organism has inheritedthat improves its chances for survival in itsenvironment or its reproductive success.* Students will recognize the various adaptations of plants andanimals and understand how they use their adaptations forsurvival.
**A monkeys strong tail is anadaptation that helps it holdonto tree branches. Thisadaptation aids in monkeyssurvival by allowing them totravel easily through trees whenthey are looking for food andescaping from predators.
**The manzanita tree has anadaptation that allows it to controlthe supply of nutrients and waterto certain branches so others canuse them to grow. This helps thetree survive in its environmentbecause it can continue to groweven when water and nutrients arescarce.
**Seals are able to holdtheir breath underwaterfor long periods of timewhile they hunt for food.This is an adaptationthat improves the sealschance for survival in itsenvironment.
**Anything that is not a behavioral or physicalcharacteristic of an organism that increases itschances of survival or reproductive success isnot an adaptation.*The pond where a fish lives, the type of food abear eats, or the conditions around a plant arenot adaptations.
*ADAPTATIONS*To improve their understanding of adaptations,students can visit a zoo, aquarium, or pet storeand write down examples of the differentadaptations animals display. Next to eachadaptation, have the students write down howthe adaptation helps the animal. Students canalso create an imaginary plant or animal thatdoesnt live on the earth, draw a picture of theorganism, and explain some of the adaptationsthe organism would have to have to help itsurvive in its habitat on the planet it lives.
**MAKE SURE YOUR NAME, DATE, AND PERIOD AREON THE TOP OF YOUR PAPER*TURN IN YOUR WORK (IN YOUR TEACHER’SHANDS, TO AN ASSIGNED STUDENT, OR IN THETRAY ON YO UR TEACHER’SDESK)*HAVE A GREAT AFTERNOON!
**A printed worksheet can accompany thisslideshow, to help students focus on the mainideas.*The content of the worksheet that I producedto accompany this slideshow is found on thefinal slide (next).*Feel free to cut this content and paste into aword document to use for yourself.
Number ofWHITE miceNuBROriginalPopulation12FirstGenerationSecondGenerationThirdGenerationAbiotic factors:________________________________________________Biotic factors (alive):________________________________________________Biotic factors (not alive):________________________________________________Food ChainsFor example, a forest food chain might look like this:________________ ________________ ________________Or, in the ocean, like this:________________ ________________ ________________Natural SelectionIf there is a species of varying brownish-white mice that live in the forest, the individuals that are mostly white will not survive asWhy? ________________________________________________________________________________________________________________________________________________________________This means that the mostly brown mice will live to reproduce and the white ones will not. The offspring of these mostly brown mThe change in a species characteristics develop over very long periods of time because there are only slight changes in the organ