Unit 1
Biological Principles
What is Biology?
• Bio= Life
• ology= Study of
Divisions of Biology
• Botany: Study of Plants
• Zoology: Study of Animals
• Microbiology: Study of small organisms
• Genetics: Study of heredity
• Evolution: Study of change over time
• Ecology: Study of organisms and their
environments
Levels of Biological Organization
6 levels of organization for all living things
6. Organism
5. Organ Systems
4. Organs
3. Tissues
2. Cells
1. Organic Molecules
• Organic Molecules: Molecules that make all
living organisms
• Cells: The smallest units of all living organisms.
Have small parts called organelles.
• Tissues: A group of cells that has the same
function.
• Organs: A group of tissues that works together
to accomplish the same function
• Organ systems: A group of organs that works to
accomplish the same function
• Organism: A group of organ systems
Functions of all living things
• Nutrition: Getting food
• Digestion: Changing food to useable form
• Absorption: Getting water, ions and food from
the environment
• Biosynthesis: Using food to make new organic
molecules
• Respiration: Breaking down food to release
energy
• Excretion: Separation of waste from body tissues
• Secretion: Making special chemicals that affect
other cells
• Response: Change due to stimulus (light, heat,
pressure) from environment. Ex: Locomotion
• Reproduction: Cells dividing to make new cells
(Mitosis)
• Metabolism: Total of all chemical reactions that
build up and tear down complex molecules
(proteins, starch, sugar…etc).
What exactly is Science?
• It is a body of knowledge that is constantly
changing (dynamic)
• The goal of Science is to understand principles
• Science starts with data
– Data= observations
– Two types:
• Quantitative: Uses numbers
– “There are 5,000 cells in this sample”
• Qualitative: Uses the senses
– “There is black fungi growing on the bread”
Experimental Design
• Inference: Making a statement based on what
you know
• Control Group: In an experiment, this is the
group that is not changed
– You always know the outcome for this group
• Experimental Group: In an experiment, this is
the group that is experimented on
– This group is where you gather data to compare to
the control group
• Independent variable: The part of the
experiment that is controlled by the person
doing the lab.
– “I” control this variable
• Dependant variable: The part of the
experiment that changes depending on what
the person does to the independent variable
• Constant: What does not change in an
experiment
The Scientific Method
• The method used in all scientific
experimentation
• Is a logical, step by step method for discovery
• Observation: State the problem that you are
trying to solve
• Hypothesis: Create an “if/then” statement
– If I put my hand in a beaker of boiling water, then it
will burn me.
• Experiment: Complete your experiment
• Analysis: What did the experiment show you?
– Did the experiment prove your hypothesis to be
true?
• New Hypothesis: If your hypothesis was proven
false, create a new one depending on what you
discovered
• Experiment again!
Theories in Science
• Theory: A possible explanation to a problem
that is backed by evidence
• Can be changed when new evidence is
discovered
• Are usually not easily accepted in science, thus
not proven
• Examples: Theory of natural selection, germ
theory
How do we measure in Science?
• Metrically!
• Base units:
– Grams- Weight Measurement
– Liter- Liquid Measurement
– Meter-Length Measurement
Abbreviations
Prefix
Meaning
k
h
da
Kilo hecto deka
1000 100
10
Practice Problems:
• a. 90 cm= __________mm
• b. 60 mL= __________ cL
• c. 12.2mg= _________ g
• d. 602m= __________mm
• e. .51L= __________ mL
g,l,m
base
1
d
c
m
deci centi milli
.1
.01 .001
How do we see small objects?
• The microscope!
– Micro= small
-Scope= to view
• Magnification: The power to make objects
larger
• Resolution: The power to show details clearly
• Specimen: What you are viewing
Ocular
Body Tube
Revolving Nose
Piece
Arm
Objectives
Stage Clips
Coarse
Adjustment
Fine
Adjustment
Base
Stage
Diaphragm
Light Source
Power
Ocular
Total
Magnification
Scanning
4
10
40
Low
10
High
40
Oil
Immersion*
100
Objective
Comp Book Time!
Complete Catch It Question 12