1 Scientific Method & Microscopes Flashcards
What is biology?
the study of life
What is a hypothesis?
A proposed explanation for a set of observations
What is the difference between null and alternative hypothesis?
Null hypothesis has “no effect” while alternative hypothesis has “an effect”
What is descriptive research investigations?
Detailed observations and measurements to describe the characteristics of a phenomenon, situation or population (uses quantitative-measure and qualitative data-senses)
What is comparative research investigations?
Collecting data on different organisms and/or population in two groups, in attempt to draw a conclusion about them
What is experimental research investigations?
Research conducted with a scientific approach using two sets of variables
What is not included in a comparative research investigation?
Independent & dependent variables, control & experimental groups, and sometimes hypothesis & prediction
What is not included in descriptive research investigations?
Control & Experimental group
What are variables?
Factors that may be expected to change during the course of the experiment
What is independent variable?
Variable that is manipulated or changed during the experiment
What is dependent variable?
variable being tested and measured in respond to the independent variable
What is standardized variable?
variable that remain the same and could have an influence on the outcome of the experiment
What is the difference between experimental and control treatments?
In experiments treatments, the independent variable is manipulated and in control treatments, the independent variable is eliminated or set to a standard condition
What publication helped advance microscopy?
Micrograph by Robert Hooke in 1665
Which microscopes produce a 3-dimension image?
Stereoscopic or dissecting microscope & scanning electron microscope
Which microscope produces a 2-dimension image?
Compound or light microscope & transmission electron microscope
What is the magnification and resolution of stereoscopic microscope?
300 X and 120 nm
What is the magnification and resolution of compound microscope?
2000X and 200nm
What is the magnification and resolution of scanning electron microscope?
100,000X & 10nm
What is the magnification and resolution of transmission electron microscope?
100,000X & 0.2 nm
What is stereoscopic microscope used for?
To view the parts or entire organism (larger objects)
Ex: minerals or insects
What is a compound microscope used for?
To view the small objects
ex: very small specimens or objects (can’t be seen with a naked eye)
What is scanning electron microscope used for?
To view the outer features of small objects (coated with gold and black&white)
Ex: the surface of biological sample
What is transmission electron microscope used for?
To view the inner features of small objects or thin sections of objects
ex: study internal ultrastructure of cells
