Wh t I as Life science, also called biology, IS the study of living things The term biology comes from the Greek words bios (life) and logos (knowledge) Li"e Science? All living things: are made of cells; obtain food to make energy; grow and develop, reproduce, respond and adapt to their environment Cells Cells: • are the smallest unit of life • are the basic unit of structure for all living organisms • create, modify, and utilize proteins which direct all cellular activity • compose and manage nearly every aspect of living organisms • carry messages that control how organisms move, eat, and react • can be eukaryotic (contain a membrane-bound nucleus) or prokaryotic (do not contain a membrane-bound nucleus) • are microscopic meaning they can only be seen through a microscope Organisms: • can be unicellular or consist of a single cell (e.g , bacteria, amoebae, some algae) • can be multicellular or consist of many cells (e.g , plants, animals, people) HOW IT ALL WORKS TOGETHER AnI Cells: • lack a rigid cell wall (present in plant cells); therefore, animal cells: - exist in a variety of shapes, depending on their function in an organ ism -can change shape easily - can sometimes completely ribosome surround and engulf other cells or microorganisms (organisms only visible through a microscope) - can transport substances into and out of cytoplasm themselves rela lysosome tivelyeasily • most animal cells: - are surrounded by a cell membrane - are centered around a nucleus - contain various organelles (miniature organs with specific functions) cell membrane cytoplasm cytoskeleton HOW IT ALL WORKS TOGETHER Plant Cells: vacuole nucleus mitochondrion rough endoplasmic reticulum chloroplast smooth endoplasmic reticulum cell wall Organelle: cell membrane ! Primary Function{s): • encloses the cell • is semi-permeable, allowing some substances to move in and out of the cell cell wall ' • is made of cellulose , • bonds with other cell walls to form structure of plant • helps the plant stay upright chloroplast • contains chlorophyll, which gives plants a green color • absorbs energy from the sun • performs photosynthesis cytoplasm • is a watery substance that fills the cell endoplasmic reticulum (smooth and rough) • transports proteins to other parts of the cell Golgi complex • stores proteins mitochondrion : • converts food particles and oxygen into energy nucleus Goigi complex • controls all cell activity • contains chromosomes with necessary information for making new cells and organisms vacuole • is an area used for storage • stores water, pigments, and sugars ! • is a watery substance that : fills the cell • provides the cell with its shape endoplasmic ! • transports proteins to other ~t.i~.~I~~ : y~~.~fthe cell G?~~omplex! • s~?r.e.s p.~?~~.i~~ lysosome • destroys old organelles and dangerous substances mitochondrion • converts food particles and oxygen into energy nucleus ! • controls almost everything : that happens in the cell .: ~ ~?~ses genes ribosome : • makes new proteins, which direct most cellular activity - r • possess a rigid cell wall; therefore, they: - are mostly square or rectangular in shape - cannot change shape or size - are easily distinguished from animal cells • most plant ce lls: - are generally larger than animal cells - are surrounded by a cell wall and a cell membrane - are centered around a nucleus - are directly attached to other plant cells via the cellulose-rich cell wall - have direct links to neighboring cells through small pores in the cell wall - contain various organelles including chloroplasts (unique to plant cells) - possess vacuole s that: o occupy most of the cell and store various substances o cause plants to appear stiff and "full" when they are full of water a cause plants to appear wilted when they are lacking water a cause plants to exhibit a specific color when full of pigment : • encloses the cell : • is semi-permeable, allowi1.lg , some substances to move m and out of the cell vacuole : • is a storage area in the cell I Cellular Digestion, Respiration, I Growth & Division DIGESTION: I • animal cells: I - obtain food through the digestive system - obtain oxygen through the respiratory system • plant cells: - obtain food through photosynthesis - obtain oxygen through pores on the leaves (stomata) • animal & plant cells: - pass food particles and oxygen through cell membranes by diffusion (the movement of particles from an area of higher concentration to an area of lower concentration) - pass water through cell membranes by osmosis (the movement of water from an area of higher water concentration to an area of lower water concentration) RESPIRATION: • is the process cells use to conve rt food particles into energy • stores energy in the form of ATP (adenosine triphosphate) • can occur in the presence or absence of oxygen - aerobic respiration: o occurs in the presence of oxygen o utilizes the Krebs cycle (citric acid cycle) to produce energy o releases a significant amount of energy (38 ATP) o is significantly more efficient than anaerobic respiration o produces carbon dioxide and water as waste products - anaerobic respiration: o occurs in the abse nce of oxygen o utilizes fermentation to produce energy a releases less energy than aerobic respiration (2ATP) o produces different waste products, depend ing on the organism Cells (continued) GROWTH & DIVISION: o all living organisms begin life as a single cell o plants and animals have cells that reproduce through mitosis - the nucleus divides in order to form two identical cells with the same number of chromosomes o plants and animals have cells that reproduce through meiosis - the nucleus divides in order to form two new cells with half the number of chromosomes o prokaryotic cells reproduce through binary fission - the cell pulls apart to form two identical cells DNA, Genes C o are passed from p arent to offspring contributing to similarities between generations DNA: CHROMOSOMES: o is t he complete database of information for char o are coiled-up strands of DNA acte ristics a nd t raits of an organism o are packed inside the ce ll nucleus o is fou nd in the nucle us of every cell o usually occur within the nucleus as matching pairs GENES: called homologous pairs o are the working subunits of DNA o vary in number depending on the orga nism o a re se gments along the DNA strand with instruc tio ns for how cells should act Fun a ,,~: o contain informatio n for how each pa rt of an organ o Each cell contains more than six feet (two meters) ism develops grows and functions ofONA o occur in variat ions called allele s that determine o If all of the DNA from a single human being wen~ specific t raits for an organism lined up end to end, it would stretch to the moon and bacl{ J,ooo times Classification System o Biologists use a classification system to divide living organisms into smaller groups with similar characteristics o Taxonomy is the science of classifying or arranging living things into groups based on characteristics they share o The most commonly used system was created by the 18th-century Swedish botanist Carl Linnaeus o o o o o o o Classification divisions, from most inclusive to least inclusive: DOMAIN KINGDOM PHYLUM CLASS ORDER FAMILY GENUS SPECIES The three domains are bacteria, archaea, and eukaryota: - bacteria are single-celled prokaryotic organisms - archaea are similar to bacteria but share many genetic similarities with eukaryotes - eukaryota include living things in all but the monera kingdom Plants are multicellular organisms with a true nucleus Most plants contain chlorophyll and make their own food Plants are not able to independently move from one place to another The plant kingdom is one of the largest groups of living things with more than half il million different species Examples include: algae moss ferns flowering plants and trees Parts of a Plant LEAF: o absorbs sunlight for plant to convert to energy o stores chlorophyll and is the site of photosynthesis o can be wide and flat (as in a maple leaf) or long and thin (as in a cactus spine) STEM: o supports leaves and flowers o carries water, minerals, and food up and down between the plant's leaves and roots o can be small and thin (as in a flower) or tall and thick (as in a tree) o helps plant grow in a direction toward energy sources o has light-sensitive tips to ensure growth toward light ROOT: ST E M - - -f-I o grows down into the soil or water o anchors plant to the earth o absorbs water and minerals needed for growth o includes varieties, based on structure: - taproots: single large root with a few smaller, branching roots - fibrous roots: many small roots branching off in different directions Photosynthesis Photosynthesis is the process by which plants take energy from the sun and combine carbon dioxide and water to produce food D B II II Carbon dioxide from the air enters the leaves through their stomata Water from the soil is absorbed through the roots Sunlight energy is absorbed through chlorophyll, found in the leaves of most plants The chlorophyll uses the sun's energy to split water into hydrogen and oxygen Hydrogen combines with carbon dioxide to form glucose (a sugar), and oxygen is released through the stomata o o The five kingdoms are plants, animals, monera (prokaryotic bacteria), protists, and fungi binomial nomenclature: - is the two-part name assigned to every living thing - is based on, and attributed to, the Linnaean biological classification - is a living thing's Latin name, based on its genus and species SUGAR: o is one of the results of photosyn thesis o is the source of energy for plants o is transported around the plant to where it is needed o sometimes undergoes respiration, resulting in carbon dioxide and water o can combine into starches, which are stored by plants and used for energy when needed Transportation System VESSELS: o xylem vessels carry water and dis solved minerals from the roots to the rest of the plant o phloem vessels carry the saplfood manufactured in the leaves to all parts of the plant TRANSPIRATION: o begins with water absorbed through roots by osmosis o results in water evaporating from leaves o cools leaves and protects them from the sun o also causes a kind of suction, draw ing water up the stem from the roots Flowering Plant Reproduction POLLINATION: o is the first step of flowering plant reproduction o is the transfer of pollen from one flower to another o involves both female (pistil) and male (stamen) parts o occurs when insects, wind, or water transfer pollen from the stamen of one flower to the pistil of another flower of the same species: - flowers pollinated by insects are often colorful and scented - flowers pollinated by wind often have small, green flowers Pistils: o are the female part of a plant o are composed of a stigma, style, and ovary: - stigma: sticky surface at tip that captures and holds pollen - style: stalk-like structure that holds up the stigma - ovary: part of the pistil that makes the flower's eggs o generally appear as a short, thick stalk in the center of a flower o are surrounded by stamens Stamens: o are the male part of a plant o normally appear as spindly stalks sur rounding the pistil o contain anthers at the tip where pollen is produced FERTILIZATION: o is the second step of flowering plant repro duction o begins when a tube grows from the pol len grain, through the stigma, and into the ovary • o continues when a male gamete (sex cell) travels through the tube and enters the ovary, which contains one or two egg shaped ovules o is complete when the male gamete fuses with the female gamete in an ovule GERMINATION: o begins after fertilization o is characterized by the ovule turning into a seed and the ovary turning into a fruit o is successful when the fruit detaches from the plant and disperses its seeds o results in the growth and development of new plants Seeds: o contain a plant embryo (the start of a new plant) o contain a store of food to help with growth o settle in soil, swell with water, and break open to allow a new plant to grow Monera, Protists, ~ ngi Animals • Animals are multicellular organisms, where each cell has a true nucleus • Animals obtain the energy they need by eating other organisms • Some animals eat only plants (herbivores); some eat only animals (carnivores); and some eat both animals and plants (omnivores) • Animals move from one place to another with the help of cilia, flagella or muscular organs • Biologists divide the animal kingdom into two major groups: invertebrates (without a backbone) and vertebrates (with a backbone) Invertebrates • Invertebrates make up about 98% of all animal species on Earth • With such an immense variety of life, the only shared trait is the lack of a backbone • Some have specialized internal organs and systems; others have no specialized organs at all • Invertebrates have a very basic nervous system and usually act according to instinct Phyla: - • With no backbone, symmetry developed as an organizational pattern : - bilateral (mirror-image) symmetry: an imaginary line divides animals into equal and similar halves - radial symmetry: animals are equally and similarly divided by rays from a central point ; Characteristics: Examples: Annelids : • have segmented bod ies : • have elongated , cylind rical bodies ~ • are bilaterally symmetric Arthropods • • • • : segmented worm, : earthworm, leech ~ insects (d ragonfly, bee, have segmented bodies have jointed limbs have a hard exoskeleton most belong to major groups: - insects (have legs) - arachnids (have legs) - crustaceans (have 10 or more legs) • form the largest group of invertebrates : ant), arachnids (spider, ! scorpion), crustaceans ~ (crab, lobster, krill), : centipede, millipede Echinodenns • have star-shaped bodies and live in water ~ starfish, sea u rchin, : sand d ollar Mollusks • have soft, muscular bodies • most have a shell inside or outside their bodies : snail, clam, octopus Monera are bacteria, or single-celled ~® organisms without a true nucleus • Bacteria lack a nucleus, mitochondria, endoplasmic reticulum, and chloro plasts • Bacteria reproduce through fission; cocci spirilla they pull apart and create two new bacteria cells • Bacteria can exchange DNA with othe r organisms or cells to mutate and survive: - through this genetic transformabacilli tion, bacteria become resistant to antibodies/vaccines • All bacteria require carbon to grow and reproduce • Bacteria can be classified according to shape, oxyge n re quire ments fo r survival, and source of carbon -shape: o exist as rods (bacilli) spheres (cocci) and spira ls (spirilla) - oxygen requirements: o aerobic bacteria - need oxygen for survival o anaerobic bacteria - not need oxygen and may die in its pres ence - carbon source: o autotrophic bacteria (autotrophs) - obtain carbon from carbon dioxide: > some contain chlorophyll and photosynthesize food and energy > autotrophs depend on energy from inorgani c sources o heterotrophic bacteria (heterotrophs) - obtain carbon from the ir environment: > most bacteria are heterotrophs > heterotrophs depe nd on en ergy from organic sources > contain enzymes on their cell surfaces that break down organ ic matter > possess enzymes capable of breaking down ce ll walls in plants > convert solid matter into compounds, which are then absorbed > break down these compounds into carbohydrates, sugars, an d acids Protists are mostly sing le-celle d eukaryotic organisms Vertebrates • Ve rtebrates make up about 2% of all animal species on Earth • Vertebrates belong to only one of 30 phyla in the animal kingdom • They are characterized by a spinal column composed of boney vertebrae • The spinal column provides structural support to the body and protects the spinal cord • Vertebrate animals are complex organ isms with many specialized organs and interconnected systems: - systems include: circulatory, digestive, endocrine, immune & lymphatic, integu mentary, muscular, nervous, reproduc tive, respiratory, skeletal, and urinary - vertebrates have a highly-developed nervous system : E.'.'~~ ,I.~~: Type: Characteristics: Amphibians : : : • can live in water (have gills) or on land (have lungs) : frog, toad • have smooth, moist skin • lay eggs in water • are cold-blooded (cannot regulate their body temperature) Fish Reptile s Birds • • • • • ; • have bod ies covered with scales : • b reathe with lungs ~ • lay leathery-shelled eggs on dry land : • are cold-blood ed • • • • • Mammals live in water breathe through gills use fins to swim have bodies covered with scales are cold-blooded have wings with feathers most can fly have beaks lay eggs with hard shells are warm-blooded (can regulate their body temperature) : goldfish, shark, ! ray : lizard, snake, : alligator parrot, ostrich, cardinal , • have bodies covered with hair or fur • give birth to fully-developed young that grow insid e mother's body • are fed with mother 's milk • are warm-blooded : whale, dog, : kangaroo, : human • Some protists are multicellular • Protists are classified accord ing to type: animal-like, plant-like, and fungus-l ike - animal-like: o have complex life cycles o active ly move through their environment o may consume other organisms o examples include amoeba and paramecium amoeba - plant-like: o use photosynthesis to convert sunlight into energy o form integral part of fo od web in watery e nvi ronments o examples include algae and euglena - fungus-like: o produce spores to reproduce and absorb nutrients o can surround and ingest food o can move through their environment o examples include some molds • Many protists have one or two flagella (single whip like appendage) cilia (multiple hair-like append ages) or pseudopods (finger-like projections of cytoplasm), enabling active movement • Protists can reproduce sexually (spores) and asexually (binary fission ) -Fungi are mostly multicellular organisms • Some fungi are single-celled • Fungi are heterotrophs - they not make their own fo od: - some secrete enzymes to break down food into smaller substances and components - some are parasites that feed off other plants and animals - some are symbionts that live together with other organisms to mutu al benefit • Fungi have no means of independent transportation - they cannot move on their own • Examples include mushrooms, molds and yeast What Is Ecolog! Ecology is the study of IMng things in their e nvironme nt (their natural surround ings) and how they affect each other Ecological OrganIzatIon Living things can be studied at six different levels: INDIVIDUAL: • is an organism belonging to a particular species POPULATION: • is a group of organisms of the same spe cies living together in a specific area • is the total count of individuals within a group COMMUNITY: • is made up of populations of different species living together in the same area • these organisms usually interact and depend on each other ECOSYSTEM: • is a system in which biotic (living) organ isms interact with each other and their abiotic (nonliving) environment • abiotic environments include things such as sunlight, soil, moisture, temperature, and nutrients BlOME: • is a region with a distinct climate (weather patterns over a period of time) • climate determines the types of organisms that can live within the biome • is identified by its flora (plants) and fauna (animals) • Earth is divided into distinct land biomes BIOSPHERE: • is the sum of Earth's biomes • is the living part of the planet • extends from just above to just below Earth's surface Food Chain & Web FOOD CHAIN: ~ • is a series of organisms linked together in the ~, order that they feed on i\ ~ J each other ~ • linear graphs depicting energy flow among organ~ / isms as a series of links • energy passes from the organism being eaten to the organism that eats it • most food chains only consist of four or five links • food chains illustrate one possible series of links t -~cIes OXYGEN CYCLE: • is the process by which oxyge n and carbon dioxide are exchange d between plants and animals: - animals use oxy gen and produce carbon dioxide (respiration) - plants use carbon dioxide and produce oxyge n (photosynthesis) u.s $4.95 NOTE TO STI ;u : \TS: This guide is inte nded for intilrllwtiol1al purposes only L>u.:: 10 its condensed rOm!a! Ihi~ guide " annOl (;(,w r C\{, I), asper t of Ill!: s ubjec t; mlher it is illlcndcd ('tH' u~c in C(llljLU1l:liilll II illl course \Iu rk and assigned U:~IS l'.ci!ll';:r lhrCharts In : ils writers editor; nor dcsigll 5!,1!l: (Ire in Il ny \\'a) rcspon~ ibl c Of liahle i\lr lhe:: US~· or m isuse of th.:: inlornml ion comaillcd ifllh i ~ gui.::lo.: C Z009 HloI r C harfs, I nc 11509 B I \ [d i tion~ ! • long, cold winters • located in the northern hemisphere • bordered on the north by tundra and on the i • short growing season south by steppe (flat, treeless region) • contains approximately one-third of all forested land on Earth (mostly evergreen conifers) • consists of many swampy areas during warmer spring months Illc .'t" ~' ...Cells (continued) GROWTH & DIVISION: o all living organisms begin life as a single cell o plants and animals have cells that reproduce through mitosis - the nucleus... system to divide living organisms into smaller groups with similar characteristics o Taxonomy is the science of classifying or arranging living things into groups based on characteristics they share... Invertebrates make up about 98% of all animal species on Earth • With such an immense variety of life, the only shared trait is the lack of a backbone • Some have specialized internal organs and