1. Studying Life What are some of the characteristics of living things?
How can life be studied at different levels?
Chapter 1 Section 3
Pages
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

2. Characteristics of Living Things
are made of cells
reproduce
are based on a universal genetic code
grow and develop
obtain and use materials and energy
respond to their environment
maintain a stable internal environment
taken as a group, change over time (evolve)
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

3. Made of Cells
Cells – smallest unit of an organisms that possesses all characteristics of life
Unicellular
composed of only one cell
Multicellular
composed of many cells
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

4. Reproduction Reproduction – process of making more of own kind
Sexual –
two special cells (gametes)
two parent individuals
new individual different from either parent individual
Asexual –
No special cells
one parent individual
new individual identical to parent individual
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

5. Based on a Genetic Code Genetic Code – determines inherited traits
DNA or RNA – carries inherited traits in all organisms on Earth
Mechanisms of control are the same in all organisms on Earth
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

6. Growth and Development
All living things grow during their lifetime
Unicellular
increase in size (growth)
Multicellular
increase in size
increase number of cells
cells take on different roles (differentiation)
may have different forms (development)
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

7. Need for Materials and Energy
Metabolism – combination of chemical reactions needed to stay alive
Anabolism (Synthesis) –build up materials.
Catabolism (Decomposition) –break down materials
to release energy
to get substances needed to build up.
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

8. Response to the Environment
Stimulus – a signal to which an organism responds, usually involves a change.
External Stimuli – changes outside
light
temperature
sounds.
Internal Stimuli – changes inside
pain
chemical levels
pressure.
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

9. Maintaining Internal Balance
Homeostasis – internal conditions remain constant when external conditions change.
Thermostat – controls house temperature
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

10. Evolution The very slow change of groups of organisms over time
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

11. Branches of Biology Anatomy (anatomist) Biochemistry (biochemist)
Botany (botanist)
Cytology (cytologist)
Ecology (ecologist)
Genetics (geneticist)
Paleontology (paleontologist)
Study of body structure
Study chemicals of life
Study of plants
Study of cells
Study of environment
Study of heredity
Study of ancient life
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

12. Levels of Biological Organization
Biosphere
Ecosystem
Community
Population
Organism
System
Organ
Tissue
Cell
Organelle
Molecule
Life found on Earth
All life and non living in area
All life in area
All life of one species in area
Individual life
Organs work together
Tissues work together
Cells work together
Structural & functional unit of life
Cell part with function
Chemical with function
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

13. Tools and Procedures What measurement system do most scientists use?
How are light microscopes and electron microscopes similar?
How are light microscopes and electron microscopes different?
Chapter 1 Section 4
Pages
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

14. Common Measurement System
Metric System (SI System)
Decimal system (based on multiples of 10)
Units increase in 10’s to measure larger
deka- 10x
hecto- 100x
kilo- 1,000x
mega- 1,000,000x
Units decrease in 10’s to measure smaller
deci- 1/10x
centi- 1/100x
milli- 1/1,000x
micro- 1/1,000,000x
nano- 1/1,000,000,000x
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

15. Common Metric Units Length Volume Time Mass Temperature meter liter
second
Mass
gram
Temperature
degrees Celsius
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

16. Microscope
produce magnified images of structures too small to see with unaided eye.
Light Microscope
focus visible light
Electron Microscope
focus beams of electrons
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

17. Types of Electron Microscopes
Transmission (TEM)
beam through a thin sample of specimen
show inside details
Scanning (SEM)
beam back and forth over the surface
forms 3-D image
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

18. Lab Techniques Cell Cultures Cell Fractionation
grow groups of cells from a single cell
cell responses
cell interactions
Cell Fractionation
a.k.a ultracentrifugation
separate cell parts
function of organelle
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004

19. More Lab Techniques Chromatography Electrophoresis separates chemicals
based on solubility
Electrophoresis
separates chemicals
based on charge/size
DNA fingerprinting
Updated July 5, 2004
Created by C. Ippolito
July 5, 2004