Warm Up – Wed. Sept 05 Which of these would be the best resource to research the symptoms and treatment of hypoglycemia (low blood sugar)? –a. Daily television news –b. New England Journal of Medicine –c. Journal of Zoology –d. Natural History Magazine

Introduction to Biology Scientific Method

Steps 1)OBSERVATION 2)State question 3)Collect information 4)Form hypothesis ( “If…..then” statement) 1)Hypothesis – educated guess 5)Test hypothesis – “experiment” 6)Collect data 7)Conclusion and retest

Where to do experiments??? Labs Studies –Controlled atmosphere Field Studies –Observe subject in the wild –Don’t disturb subject

Factors in Experiments??? Control group –Used to compare experimental group against Experimental group –Used to experiment on… Independent Variable (Manipulated) –Thing “I” change in experiment –In a graph, goes on the X axis –Should only test 1 variable in an experiment!!!! –In a graph, goes on the X axis; Dependent Variable (Responding) –Thing that is recorded because of what was manipulated – Data –In a graph, goes on the Y axis

Constants in an experiment…. A constant in an experiment is what stays the same in both the experimental group and the control group…. –For example: Testing tap water vs. spring water on plant growth –Constants – soil type, plant species, pot size, temp….

Data 2 types –Quantitative Amounts, numbers, - think quantity –Qualitative Colors, shapes – think of quality of data Can show data as –Graphs –Lists –charts

Theory –Hypothesis that is supported over time –Can be revised or replaced

Little Tidbit of History Redi – a.k.a. “The maggot man” –Didn’t believe in spontaneous generation Means life comes from nonliving things –Maggot – Rotting meat experiment Used scientific method to disprove spontaneous generation –Results Maggots appeared on vial with no gauze Disproved spontaneous generation

Ice Man

EXIT PASS: What variable in an experiment do “I” change?

Warm Up – Thursday, Sept. 06 How many variables should I test in an experiment? –A. 2 –B. 3 –C. 1 –D. 4

Chapter 1.3 Studying Life

Biology The study of life –Bio- life –-ology- the study of –Biology – the study of life

Characteristics of Life All Living things: –Made up of units called cells –Reproduce –Based on universal genetic code –Grow and develop –Obtain and use materials and energy –Respond to their environment –Maintain a stable internal environment –As a group, change over time

Made Up of Cells Cells –A collection of living matter enclosed by a barrier that separates the cell from its surroundings –Smallest units of life –Unicellular- one celled –Multicellular- more than one cell

Examples…. Unicellular –Ex. microorganisms in Pasteur’s experiments Multicellular –Ex. animals, most plants

Reproduction Two kinds: –Sexual Two cells from different parents unite to produce the first cell of the new organism –Asexual Single parent Two kinds: –Vegetative- grows off of parent, and breaks off –Binary fission- cell splits

Based on Genetic Code In asexual reproduction - offspring is genetically identical to parent In sexual reproduction – offspring is genetically different from parents Genetic code stored in DNA –Determines inherited traits of every organism on Earth

Growth and Development During development a single fertilized egg cell divides again and again to produce all the cells of a mature organism –Cells change in shape and structure as cells differentiate Differentiate = specialize Growth is simply an increase in the size of the organism

Need for Materials and Energy Need constant supply of materials and energy just to stay alive Combination of chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes Some use photosynthesis Some use cellular respiration Some use energy from decomposition

Response to the Environment Respond to stimulus –A signal External stimuli –Light –Temperature Internal stimuli –Blood glucose level

Maintaining Internal Balance Homeostasis –The process of maintaining a constant internal balance If too hot will sweat –This cools the body If too cold will shivers –This warms the body up

Evolution Change over time Takes hundreds or millions of years Species change in response to their environment

Branches of Biology Can be studied from various levels: –Molecules –Cells –Organisms –Populations of a single organism –Communities of different organisms –Biosphere Zoologists- study animals Botanists- study plants Paleontologists- study ancient life

EXIT PASS The smallest unit of life considered living is a __________.

Warm UP – Friday, Sept. 07 The variable that is CHANGED in an experiment is known as the… a. Dependent variable b. Independent variable c. Control d. Constant

Measurements Ch. 1.4

Metric System The metric system of measurement that bases all its units on multiples of 10.measurement Base Units: –Mass – gram –Length – meter –Volume - liter

Graphs Represent data in picture form ALWAYS label X and Y axis ALWAYS label title ALWAYS mark units

Whats wrong with this graph???

Microscopes Compound Light microscope –Uses light –Objects can be living or dead Scanning Electron Microscope (SEM) –Uses Electrons –Objects must be dead –3D image Transmission Electron Microscope (TEM) –Uses Electrons –Objects must be dead –Cross section image

Lab Techniques Cell culture –Grow cells on petri dish Fractionation –Separate parts of cells Centrifuge –Machine used for fractionation

Exit Pass The picture shows a cover slip correctly being lowered onto a slide. This method is used because it — a. prevents the escape of microorganisms found in the water b. reduces the possibility of air bubbles on the slide c. prevents the cover slip from moving d. allows microorganisms to move freely in the water

Warm UP Convert the following measurement from cm. to mm. = 45.0 cm  __________mm

Exit Pass The formula to find out the total magnification of an object is….. Occular lens X _________ = total mag.