intro to ‘biology’ biology – the science of life organism – a “living thing”...
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Intro to ‘Biology’
Biology – the science of life
Organism – a “living thing”
Therefore, biology studies organisms
∙ microscopic structure
∙ interaction among many
∙ life history
THEMES of BIOLOGY
• Evolution – change over time• Reproduction & Inheritance – DNA/Genetics
• Structure & Function – examples???
• Energy – required for life
• Ecology – interactions
Science & Society – conservation, bioethics, etc.
What is Life???Think about some of the things you see in your everyday life…
Animals Trees Rocks WaterSoil Buildings Cars
• You probably have an idea about which of these is alive and which are not.
• Scientists use the following characteristics to determine if something is alive or not. In order to qualify, the thing in question much possess all of the characteristics.
The Characteristics of Life:• made of cells• has organization• uses energy• responds to the environment• grows• reproduces
* Try applying these to the list above*
Use the word fragments in your list to figure out the meaning of the following terms:
1. Hydrology 11. Endocytosis
2. Cytology 12. Insecticide
3. Protozoa 13. Anaerobic
4. Epidermis 14. Bilateral
5. Spermatogenesis 15. Endotherm
6. Cytoskeleton 16. Subspecies
7. Abiotic 17. Arthropod
8. Dermatitis 18. Micrometer
9. Hypodermic 19. Hypothermia
10.Hemophilia 20. Photosynthesis
STRUCTURES AND FUNCTIONS
Write the correct term—autotroph or heterotroph—in the space referring to each of the organisms pictured below.
The Scientific Method
What is it used for???• Answering questions about the world around us• It does so in an organized and systematic way
THE STEPS OF THE SCIENTIFIC METHOD• Identify the problem/question• Observe• Form a testable hypothesis• Experiment (collect data)• Analyze data• Draw a conclusion • Repeat!
Experimental Design• Pre-planned series of steps• Goal is to collect (good) data• Most important part of the Scientific Method• “Controlled Experiment”
– Gathers data under controlled conditions– Comparison of two (almost identical) groups
Control Group: Receives the normal (control) treatmentExperimental Group: Receives the experimental treatment
Independent Variable: Only difference between groups“What did I change?”
Dependent Variable: Data gathered during experiment“What did I measure?”
Drawing a Conclusion• Analyze your data by creating charts/tables/graphs
• Look for patterns/trends • Your results should point towards a conclusion...
EITHER:
“the data collected supports… (the hypothesis)”
OR
“the data collected does not support… (the hypothesis)”
• THEORY: A statement widely considered to be true because it has been supported by extensive experimental evidence
Quantitative Data• Numerical information gathered through experimentation• Examples:
- tree branch length- cell count- colony diameter
• It is important for scientists to use a standard system of measurement
SI = international system of measurement (a.k.a. the metric system)
BASE UNITS: Length → meter Mass → gram Volume → liter
Metric Number Line
Metric ConversionsMetric Conversions1) 290,000.
2) 36.
3) 0.00007
4) 9.1
5) 10.6
6) 76.5
7) 104.9
8) 0.019
9) 0.396
10) 140.
11) 0.000025
12) 0.023
13) 0.000214
14) 5160.
15) 1.4
16) 0.2
17) 34.
18) 0.01
19) 27.6
20) 0.314
21) 41.17
22) 8,700.
Metric ConversionsMetric Conversions
23) 0.001
24) 7,100.
25) 0.0004
26) 146,100.
27) 0.0182
28) 22,100.
29) 0.0217
30) 0.0001087
Microscopy• A microscope produces an
enlarged image of an object
* MAGNIFICATION *
COMPOUND LIGHT MICROSCOPE• Used to view small organisms and cells• Thinly sliced specimen
mounted on a glass slide• 2 LENSES:
- Ocular (eyepiece)
- Objective (adjustable)• Total Magnification = ocular × objective
Compound Light Microscope Diagram
Compound Light Microscope Diagram
How to … MICROSCOPES!- If unsure, follow directions in your handout!
Read, read, read!!!- Handle the microscope with one hand on the arm
and the other giving support underneath the base- Always begin viewing under LOW power- Start with the lens as close to the
stage as possible, then pull away with the coarse knob until focused
- Once focused under low, switch to high power- Under HIGH power, only fine focus is needed
Answer all questionsMake 2 sketches for each slide viewed
Other forms of Microscopy
Light microscopes magnify with a beam of light
Electron microscopes do so with a beam of electrons
• TEM – transmission electron microscope• SEM – scanning electron microscope
Pro: Magnify many thousands of times
(instead of hundreds)
Con: Cannot view living specimens
Transmission Electron Microscope
TEM image of bacteria cells(magnified 50,000x)
SEM with opened sample chamber
SEM image of various types of pollen