BIO 140 Chapter 1
Cytoplasm
- 70-80% water - Complex mixture of sugars, amino acids, and salts - Serves as a pool for building blocks for cell synthesis or sources of energy
Science
- A way of learning - A body of knowledge produced by scientific investigation - Involves critical thinking, careful data collection, rigorous peer review, and communication of results
Prokaryotes
- Bacteria and Archaea - Lacks nucleus and histones - Lacks membrane-bound organelles
Cyanobacteria
- Blue-green algae - Some of Earth's oldest life forms
Cell
- Cella: small room - Function of cell: "building blocks of life" - Basic structural, functional, and biological unit of all known living organisms - Must be able to replicate independently
Inductive Reasoning
- From a number of observations, a general conclusion is drawn - Common in descriptive science - Involves formulation generalizations inferred from careful observation and the analysis of a large amount of data Lead to observations and then conclusion
Bacterial Chromosomes and Plasmids
- Most bacteria have a single circular chromosomes Plasmids: - Nonessential pieces of DNA - Confer protective traits such as drug resistance and toxin, and enzyme production DNA is aggregated in the nucleoid
9 Key Properties of Life
- Order - Sensitivity or response to the environment - Reproduction - Adaptation - Growth and development - Regulation - Homeostasis - Energy processing - Evolution
3 Typical Shapes of Bacteria
- Round (Coccus/cocci) - Rods (Bacillus) - Spiral (Spirillium)
Deductive Reasoning
- Used in hypothesis-based science - Uses a general principle or law to forecast specific results - Begins with a specific question or problem and a potential answer or solution that can be tested Lead to general premise and then predicted results
Human Genome Project
13 year collaborative effort among researchers who sequenced the entire human genome, which was completed in 2003
Cytoplasmic Membrane
A lipid bilayer with proteins embedded Serves as a site for: - Energy reactions - Nutrient processing - Synthesis - Selectively permeable - Regulates transport of nutrients and wastes
Theory
A related set of insights, well supported by evidence (not just a hunch)
Hypothesis
A statement is knowledge obtained from logical inferences and deductive experimentation that attempts to comprehend nature - Must be testable to be valid - Should also be falsifiable (can be disproven) - Proven or eliminated using one or more experiment
Evolution
Accounts for the unity and diversity seen among living organisms
Atoms
All molecules, including this DNA molecule are composed of atoms
How does most bacteria function?
As independent single-celled, unicellular organisms
The diversity of science fields
Astronomy Biology Computer Science Geology Logic Physics Chemistry Mathematics
E. coli
Bacteria found in our digestive tracts that aid in the absorption of vitamin K and other nutrients
How do organisms survive?
By consuming and transforming energy All organisms maintain a stable internal environment
Genes
Consist of DNA and RNA and are the basic unit of heredity
Sir Francis Bacon
Credited with being the first to define the scientific method
Cell Wall
Determines cell shape and provides strength, usually made of peptidoglycan
1953
Discovery of double helical structure of DNA
Jean-Baptiste Larmarke
First to resent a coherent theory of evolution
Stomatolites
Formed by the layering of cyanobacteria
Cell Theory
Formed in 1838
Plant Cells
Have a cell wall, and organelles (subcellular structures) to perform photosynthesis
Basic Science
Increases the knowledge of a field of research - Only goal is to increase the knowledge base of a particular field of study
Archaea
Live at high temperatures or produced methane clustered together as a group well away from the usual bacteria and the eukaryotes
Scientific Method
Make an observation Ask a question Form a hypothesis that answers the question Make a prediction based on the hypothesis Do an experiment to test the prediction Analyze the results If the hypothesis is correct report results If the hypothesis is incorrect report results and try again
Biological Levels of Organization of Living Things
Organelles Cells Tissues Organs Organisms Ecosystems Biosphere
Gram-Negative Cell Wall
Single sheet of peptidoglycan covered by an outer membrane containing LPS and porin proteins
Charles Darwin
Spread the theory of natural selection
Cell Biology
Study of cells
Biology
Study of living oranisms
Gram-Positive Cell Wall
Thick homogenous sheet of peptidoglyca which contains teichoic acid and lipoteichoic acid
Applied Science
Uses that knowledge to solve specific problems - The art or science of applying scientific knowledge to practical problems
Pleomorphism
Variation in the size and shape of cells of a single species due to nutritional and genetic differences
