1. Biology in the 21st Century

2. What is “BIOLOGY?” Bios: life/living organisms
Logy: science/study of a particular subject
Biology is the STUDY OF LIFE

3. The Study of Life

4. Earth is home to an incredible diversity of life!
Biosphere: all organisms and the part of Earth where they exist
Biodiversity: variety of life within an area
Species: group of organisms so similar to one another that they can breed and produce fertile offspring

5. Characteristics of Living Things
Cellular Structure and Function
Reproduction
Metabolism
Homeostasis
Heredity
Evolution
Interdependence

6. All organisms share certain characteristics
Cell: basic unit of life
Need for energy
Metabolism: all chemical processes that synthesize or break down materials within an organism
Response to environment
Reproduction and development
DNA: molecule that stores genetic information in all organisms

7. Unifying themes of biology

8. All levels of life have systems of related parts
System: changing, organized group of related parts that interact to form a whole
Ecosystem: collection of organisms and nonliving things, such as climate, soil, water, and rocks in an area

9. Structure and function are related in biology

10. Organisms must maintain homeostasis to survive in diverse environments
Homeostasis: regulation and maintenance of constant internal conditions in an organism

11. Evolution explains the unity and diversity of life
Adaptation: inherited trait that is selected for over time because it allows organisms to better survive in their environment
Survival of the Fittest
Unity and diversity

12. Scientific thinking and processes

13. Like all science, biology is a process of inquiry
Observations and Question(s)
Predictions and Hypotheses
Hypothesis: proposed explanation or answer to a scientific question
A hypothesis is a statement, not a question!!!

14. Biologists use experiments to test hypotheses
Experiment: process that tests a hypothesis by collecting information under controlled conditions
Independent variable: condition or factor that is manipulated by a scientist during an experiment
Dependent variable: experimental data collected through observation and measurement
Constant: condition that is controlled so that it does not change during an experiment

15. DATA Observations and measurements recorded during an experiment
_________________________________________________________
Qualitative: descriptions in words of what is being observed. Examples: color, odor, or texture.
Quantitative: numerical measurements. Objective-they are the same no matter who measures them. Examples: mass, volume, temperature, distance, time, etc.
Nonsignificant: the data show no effect, or an effect so small that the results could have happened by chance
Statistically significant: the data show an effect that is likely not due to chance

16. A theory explains a wide range of observations
Theory: proposed explanation for a wide variety of observations and experimental results
Based on scientific fact

18. Biologists’ tools and technology

19. Microscope “Talk”
Magnification: the quality of making an image appear larger than its actual size
Resolution: measure of the clarity of an image
Micrograph: picture taken with a microscope, usually tells what kind of scope and magnification

20. Light Microscope
Light passes through one or more lenses to produce an enlarged image of the specimen
CAN use living organisms
Max magnification 2000X
Invented by Leeuwenhock
Enables us to see cells

21. Electron Microscope Sends a beam of electrons through the specimen
CANNOT use living organisms
Max magnification 200,000X
Invented in the 1930s
Enables us to see fine structures inside cells and on cell surfaces

22. Transmission Electron Microscope (TEM)
Thin slice of specimen stained with metal ions
Images are in black and white
Cells internal structures seen in detail

23. Osteoporosis in bone, worm

24. Scanning Electron Microscope (SEM)
Specimen coated with a thin layer of metal
Images are in black and white
Cell external structures are seen in detail

25. Spider, flowers, ice-cream, termite

26. Scanning Tunneling Microscope
Needle-like probe measures differences in voltage of electrons moving on the surface of the object being viewed
Computer tracks movement
Individual atoms can be seen
CAN use living organisms

28. Imaging technologies provide new views of life
Microscope: tool that provides an enlarged image of an object
Medical Imaging: not limited to microscopes! X-rays, MRI (magnetic resonance imaging)
Complex systems are modeled on computers too!

29. The tools of molecular genetics give rise to new biological studies
Gene: specific region of DNA that codes for a particular protein
Molecular genetics: study of DNA structure and function on the molecular level
Genomics: study and comparison of genomes within a single species or among different species
Example: The Human Genome Project

30. Biology and your future
Biology and your health
Biology and the world around you

31. Benefits and biological risks
Biotechnology: use and application of living things and biological processes
Benefits and biological risks
Transgenic: organism whose genome has been altered to contain one or more genes from another organism or species
Benefits and ethical considerations

32. Biology presents many unanswered questions… maybe you will answer them!