The Science of Biology

What is Biology? The study of living things, their environment and their behavior within their environment. What is ? Science an organized body of knowledge that has developed through observation and experimentation

Thinking Like a Scientist

A systematic approach to problem solving Scientific method Recognize (State) the Problem Gathering Information Form a Hypothesis Test Your Hypothesis Record Data Analyze Data Draw Conclusions Develop New Questions

Step One: State the Problem What question are you trying to answer? Begins with ______________- observations use of the 5 senses to gather facts or data about events and processes Written in the form of a _____________________ question

Step Two: Gather Information Ask questions Research Repeatable observations are known as ___________. facts

Step Three: Forming a Hypothesis What do you think the outcome will be? Hypothesis - possible solution to the problem Must be ____________ Testable observations Based on __________

There are two groups in an experiment: Step Four: Testing the Hypothesis procedure a scientific __________carried out according to certain ___________. step-by-step ________ procedure. experiment - guidelines numbered There are two groups in an experiment: Experimental Group (receives a variable) and (Does not receive a variable) Control Group variable - a factor that can be changed.

Variables that remain the same Constants - Variables that remain the same control - Standards used for comparison Does not receive a variable change Why do you perform a control group? To avoid the possibilities of hidden, unknown variables or outliers

Group A With fertilizer Group B Without fertilizer Experimental Group Control Group

Independent (manipulated) Variable - Step four, cont Independent (manipulated) Variable - variable changed on purpose by the scientist. Dependent (responding) Variable - the factor being observed or measured.

With fertilizer Group A Group B Without fertilizer Experimental Group Independent Variable – The addition of fertilizer Dependent Variable - The amount of growth of each plant Group B Without fertilizer Control Group

A systematic approach to problem solving Scientific method Recognize the Problem Gathering Information Form a Hypothesis Test Your Hypothesis Record Data Analyze Your data Draw Conclusions Develop New Questions

Step Five: Record and Analyze Data Recorded observations and measurements Data - There is two types of data: Quantitative - expressed as numbers obtained by counting or measuring There are 4 eggs in the nest. Qualitative - descriptive The eggs are brown and white.

a method used to best understand the data Analyzing –. An opinion or prediction based on data. Inferences -

Inferences Observations The chair has 4 strong legs. The chair has 4 legs. The car is red. The car is fast.

A systematic approach to problem solving Scientific method Recognize the Problem Gathering Information Form a Hypothesis Test Your Hypothesis Record Data Analyze Your data Draw Conclusions Develop New Questions

Three Basic Graph Types Analyze Your Data a visual display of the information or data Graph – Three Basic Graph Types Line Bar Circle

Line Graph - represents “change over time” data.

A Bar Graph are useful for comparing information collected by counting.

A Pie or Circle Graph is used to show how a fixed quantity is broken into parts. Represented as percentages of the total.

A systematic approach to problem solving Scientific method Recognize the Problem Gathering Information Form a Hypothesis Test Your Hypothesis Record Data Analyze Your data Draw Conclusions Develop New Questions

Step 6: Stating a Conclusion ______________- a statement based on the results of the experiment, your hypothesis and your problem. may or may not support the hypothesis. The results from a single experiment or trial are not enough to reach a conclusion, it must be performed many times to be considered accurate and before a conclusion can be reached

A systematic approach to problem solving Scientific method Recognize the Problem Gathering Information Form a Hypothesis Test Your Hypothesis Record Data Analyze Your data Draw Conclusions Develop New Questions

What happens if the data do not support the hypothesis? Redo the experiment Designed a new experiment

Tools and Procedures

Used to contain reaction solutions Erlenmeyer Flask

Most versatile Used for ballpark estimates Beakers

Test tube and holder

Used to make accurate liquid volume measurements Graduated Cylinder

How to read a graduated cylinder. meniscus meniscus With water in glass, the ________will curve up at the edges and down in the center so we say you read the _________of it. bottom www.morrisonlabs.com/meniscus.htm

9.8 ml 31 ml 14 ml 27 ml 77.3 ml 35.4 ml 45 ml 10.3 ml

Compound light Microscopes SEM TEM

Bird’s feather on SEM Yeast spore, Froze in milliseconds with liquid nitrogen, and imaged with a transmission electron microscope.

SEM - Ant

Which type of microscope would best serve to investigate the following?

Compound light

SEM – Red Blood Cells

Characteristics of Living Things

The Characteristics of Life All living things…. …no matter how different from each other they may be…. ….share a set of common characteristics.

ALL LIVING THINGS ARE: Made of______ cells basic unit of life http://sps.k12.ar.us/massengale/study_guides_bi.htm

Organisms are grouped by their number of cells

____________organisms are UNICELLULAR ____________organisms are single cell (made of only 1 cell) bacteria (Ex: _________) http://images.search.yahoo.com/search/images;_ylt=A0oG7kqJyV5OBl4ArzhXNyoA?ei=UTF-8&p=bacteria&fr2=tab-web&fr=yfp-t-701-s

MADE OF MANY CELLS ________________ organisms begin as _________ but as adults are _________________________ Ex: (___________ __________ ) MULTICELLULAR ONE CELL MADE OF MANY CELLS a human, animals, tree, plants Images from: http://www.angelbabygifts.com/ http://www.inclusive.co.uk/downloads/images/pics2/tree.gif

Cells contain an universal _______code genetic DNA (Deoxyribose nucleic acid) the directions for inheritance, determines the inherited traits of every organism on earth

All living things _________ reproduce Two Types Sexual reproduction _____________ Seen in animals and plants combines the genetic material from _____________ 2 parents sperm + egg = baby different Offspring ________from parents Family image from: http://babyhearing.org/Parenet2Parent/index.asp

_________________________ ASEXUAL REPRODUCTION _________________________ makes a new organism using the from _________________ Seen in bacteria, plants, and some animals genetic material ONLY 1 PARENT Offspring ________ to parent identical Planaria animation: http://www.t3.rim.or.jp/~hylas/planaria/title.htm

ALL LIVING THINGS Grow & develop Growth Image by Riedell Growth _________ an increase in the amount of living material and the formation of new structures Development __________________ all of the changes (rapid and dramatic) that take place during the life of an organism

ALL LIVING THINGS Grow & develop Image by Riedell _____________ organisms, grow by ________________. SINGLE CELLED INCREASING in SIZE

Multicellular organisms grow bigger by __________________ Image by Riedell Image from: http://www.bcps.org/offices/lis/models/life/images/grow.JPG Multicellular organisms grow bigger by __________________ AND _____________________. increasing cell size increasing cell number

DIFFERENTIATION _______________________________ – as cells divides they become specialized in structure and function. Some cell change to form liver cells, some brain cells, other muscle cells

The process of changing Embryonic Stem Cells into cells that are specialized in structure and function = __________________________ DIFFERENTIATION Image from: http://www.ncu.edu.tw/~ls/graph/faculty_pictures/whole_time/SLC/SLC_lab-1.jpg

ALL LIVING THINGS Need Materials & Use Energy To grow and develop, organisms need a constant supply of building materials & energy ______ - the ability to cause change Energy http://ag.ansc.purdue.edu/sheep/ansc442/Semprojs/2003/spiderlamb/eatsheep.gif

the combination of all the _________________ through which an organism ________ or ___________ materials as it carries out its life processes = ___________________ chemical reactions builds up breaks down metabolism Our main source of energy comes from the _______ Sun

ALL LIVING THINGS Respond to their environment _____________ everything that surrounds us; living and nonliving A signal to which an organism responds = ____________ STIMULUS  Image from: http://www.travel-net.com/~andrews/images/animations/traffic.gif

A stimulus can be _________________ EXTERNAL  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

____________ INTERNAL http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookCHEM2.html A stimulus can be ____________ INTERNAL   Ex: When the glucose level in your bloodstream becomes low, your body responds by making you feel hungry. http://office.microsoft.com/en-us/images/results.aspx?ex=2&qu=eating#mt:3

Vocab Word The reaction of an organism's to a stimulus Response

VOCAB WORD Controlling an organism’s internal system to maintain constant balance - __________ HOMEOSTASIS If body temp drops too low, “shivering” produces heat to warm you up. If temp is too hot, “sweating” cools you down.

All living things adapt and evolve An inherited body structure, behavior, or internal process that allows an organism to respond to its environment and survive to produce offspring Adaptation

The gradual change in a species through adaptations over time - EVOLUTION survival Allows _______ of species in a changing world. http://cache.eb.com/eb/image?id=63386&rendTypeId=4

Characteristics of ALL LIVING THINGS Made of _________ 2. Contain ____________________ 3. Two types 4. _______ and ____________ 5. Need________ & use _______ 6. ________ to their environment maintain internal balance - 7. ________ and _________ cells universal genetic code - DNA Reproduce Grow develop materials energy Respond homeostasis Adapt Evolve

Levels of Organization Atom Levels of Organization Molecular Tissues: groups of cells that perform a specific function in an organism Muscle, nerve Organs: groups of different tissues that function together for a specific purpose Organ systems: Made of several organs working together to perform a function Cellular Groups of Cells

Organisms

Species

Population

Community

Ecosystem

An increase in size is known as a. growth. b. metabolism. c. development. d. differentiation. 78

Which of the following is NOT a characteristic of all living things? a. use of energy b. made of cells c. stable internal environment d. need for oxygen 79

The genetic code is carried in Water. DNA. Proteins. Soil. 80

a. organisms, cells, populations, molecules, ecosystems Which of the following shows the levels of organization in correct order from the simplest to the most complex? a. organisms, cells, populations, molecules, ecosystems b. ecosystems, populations, organisms, cells, molecules c. molecules, cells, organisms, populations, ecosystems d. molecules, organisms, cells, populations, ecosystems 81

The Origin of Life

Spontaneous Generation The idea that organisms developed directly from nonliving matter. "life from nonlife" Also called ______________ Abiogenesis

Biogenesis The idea that living things are produced only from other living things.

History: Abiogenesis was widely believed until the 19th century. Several scientists performed experiments that disproved spontaneous generation * Francisco Redi * Louis Pasteur

Francesco Redi, 1668

Redi's Problem Where do maggots come from? Hypothesis: Experiment: Redi put 4 types of meat into separate jars. Some covered and some uncovered Maggots come from eggs laid by flies. Keeping flies away from meat will prevent maggots.

What is the manipulated (independent) variable? What is the responding (dependent) variable?

Redi’s critics said: You have too many variables There is a lack of access and a lack of air. We ALL know that everything needs air Of course no flies grew! You haven’t proven anything.

Redi’s Conclusions: Life comes from ______ However, if someone were to demonstrate even one exception to this hypothesis, then Redi’s hypothesis would be rejected. Life

Louis Pasteur, 1864

Louis Pasteur, 1864 Finally settled the argument over “spontaneous generation” or abiogensis. Showed that all living things come from other living things

The End