WHAT IS SCIENCE? Chapter 1 Key concept: What is the goal of science?
SCIENCE: Is an Uses to events Collects and organizes Deals only with Looks for patterns and organized method evidence connections explain information natural world Image from: http://www.erschools.org/teachers/henderson/webquest/images/scientist.jpg
Scientists: propose explanations that can be TESTED by examining evidence http://www.darvill.clara.net/enforcemot/graphics/newton.gif
not just facts Science is but a WAY OF KNOWING Because of new tools, techniques, & discoveries, our understanding of science is. ALWAYS CHANGING http://www.npr.org/programs/fa/features/2005/04/flat_200.jpg http://atmos.pknu.ac.kr/~swimm/wall/1024/earth.jpg
AIDS Global warming Renewable fuels Alternative energy Stem Cell Research Cancer Endangered species Bird flu Cloning Nuclear power Pollution Our understanding of science is essential in making intelligent decisions about a wide variety of issues that affect our lives.
BIOLOGY The science of LIFE = = Study of living things Image from: http://analyzer.depaul.edu/astrobiology/kingdoms.jpg Bacteria
Characteristics of ALL LIVING THINGS 1.Made of cells 2. Reproduce 3. Based on a universal genetic code 4. Grow and develop 5. Obtain & use materials & energy 6. Respond to their environment 7. Maintain a stable internal environment 8. As a group, change over time
ALL LIVING THINGS ARE: CELL Made of cells The is the. basic unit of life http://sps.k12.ar.us/massengale/study_guides_bi.htm
ALL LIVING THINGS ARE: UNICELLULAR Made of cells organisms are made of only 1 cell bacteria (Ex: ) Image from: http://www.agen.ufl.edu/~chyn/age2062/lect/lect_06/bacsiz.gif
ALL LIVING THINGS ARE: Made of cells MULTICELLULAR organisms BEGIN as ONE CELL but as adults are MADE OF MANY CELLS Ex: ( a human a tree ) Images from: http://www.angelbabygifts.com/ http://www.inclusive.co.uk/downloads/images/pics2/tree.gif
ALL LIVING THINGS Reproduce SEXUAL REPRODUCTION combines the genetic material from 2 parents sperm + egg = baby Seen in animals and plants Family image from: http://babyhearing.org/parenet2parent/index.asp
ALL LIVING THINGS Reproduce ASEXUAL REPRODUCTION makes a new organism using the genetic material from ONLY 1 PARENT Seen in bacteria, plants, and some animals Planaria animation: http://www.t3.rim.or.jp/~hylas/planaria/title.htm
All living things share a universal genetic code Hereditary material = DNA DEOXYRIBONUCLEIC ACID Segment of DNA with PROTEIN instructions for one is called a. GENE Image from: http://sbchem.sunysb.edu/msl/dna.gif
ALL LIVING THINGS Grow & develop Image by Riedell SINGLE CELLED organisms, like a bacterium, grow by INCREASING in SIZE.
ALL LIVING THINGS Grow & develop Image by Riedell Image from: http://www.bcps.org/offices/lis/models/life/images/grow.jpg Multicellular organisms grow bigger by increasing cell size AND. increasing cell number
MULTICELLULAR ORGANISM don t just contain MANY CELLS but many DIFFERENT KINDS of cells with DIFFERENT FUNCTIONS Image from: http://www.isscr.org/images/es-cell-fig-2.jpg
The PROCESS OF CHANGING EMBRYONIC STEM CELLS into different looking ADULT cells doing different jobs = DIFFERENTIATION Image from: http://www.ncu.edu.tw/~ls/graph/faculty_pictures/whole_time/slc/slc_lab-1.jpg
All cells have the SAME DNA... different what makes them is WHICH GENES TURNED ON or OFF are See end of show for image sources
It s like having a whole library full of books, but reading only the books that are important to you. http://school.discovery.com/clipart/clip/report2.html http://www.adc.state.az.us/programs/offlibsvs.html
ALL LIVING THINGS Take in Materials & Use Energy To,organisms grow and develop need a constant supply of BUILDING MATERIALS & ENERGY! http://ag.ansc.purdue.edu/sheep/ansc442/semprojs/2003/spiderlamb/eatsheep.gif This sheep uses the MOLECULES and ENERGY in the food it eats to make more sheep
ALL LIVING THINGS Take in Materials & Use Energy AUTOTROPHS use energy from sunlight or chemicals to make their own food Image from: http://vilenski.org/science/safari/cellstructure/chloroplasts.html Ex: GREEN PLANTS use to photosynthesis turn into glucose http://www.inclusive.co.uk/downloads/images/pics2/tree.gif
ALL LIVING THINGS Take in Materials & Use Energy HETEROTROPHS get their energy by consuming other organisms Ex: Animals (including you) and most bacteria Image from: http://www.epa.gov/region5/superfund/ecology/images/fishcartoon.gif
The combination of all the chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes = metabolism
ALL LIVING THINGS Respond to their environment A signal to which an organism responds = STIMULUS Image from: http://www.travel-net.com/~andrews/images/animations/traffic.gif
ALL LIVING THINGS Respond to their environment Image from: http://www.ccs.k12.in.us/chsbs/kons/kons/images/stimresp.jpg A stimulus can be EXTERNAL Ex: When there is enough water and ground is warm enough, seed germinates. Roots respond to gravity & grow downward. Leaves respond to sunlight & grow up. http://www.nofretete-page.de/gemischtneu/tn_plant_grow_w.jpg
Ex: When the glucose level in your bloodstream becomes low, your body responds by making you feel hungry. http://www.israellycool.com/eat%20guy%20afp.jpg ALL LIVING THINGS Respond to their environment http://www.estrellamountain.edu/faculty/farabee/biobk/biobookchem2.html A stimulus can be INTERNAL
VOCAB WORD A cell works to keep conditions inside the cell constant = HOMEOSTASIS IF temperature, water content, nutrients, acidity change too much... the cell will die.
HOMEOSTASIS involves internal FEEDBACK mechanisms If body temp drops too low, shivering produces heat to warm you up. If temp is too hot, sweating cools you down. http://www.dreamstime.com/thumb_4/1099235658q3a4x8.jpg http://www.clipartheaven.com/clipart/seasons_&_weather/overheating_2.gif
HOMEOSTASIS Drinking a BIG GULP increases the amount of water in your body http://www.me-go.net/rtw/images/biggulp.jpg Your next stop gets rid of the excess water. (OSMOREGULATION) http://pluck.typepad.com/photos/uncategorized/restroom_blog.gif
ALL LIVING THINGS as a group, change over time EVOLUTION = Allows survival of species in a changing world http://cache.eb.com/eb/image?id=63386&rendtypeid=4
SOURCES Muscle:http://chemistry.uca.edu/faculty/isom/4320_pdf/multimedia/web_ex/web_ex1/skeletalmuscle1.jpg RBC: http://www.astrographics.com/galleryprints/display/gp2120.jpg Nerve: http://www.alongnaturestrail.com/the_nervous_system.html Bone: http://ssm.hkcampus.net/~ssm-is/3.%20human_cell/bone_cell.jpg Cheek: http://faculty.stcc.edu/nash/cheek1.jpg