All organisms are interdependent, and humans are organisms.
In order to understand life on earth and the future of humans and other organisms. Biologists study interactions between living things and their (our) environment
In order to be considered alive and organism must have the following characteristics living things:
Organism: any living individual
8 Common traits:
1. Have cell structure (organized)
Number one (unicellular) to many (multicellular)
Structure- same for all organisms, but range of complexities
Cells- a variety organized into organs
Tissues- a variety organized into organ systems
Organ system: a variety organized into complex organism
2. Reproduction: can reproduce- make more of own kind (not necessary to individual survivor)
Include mechanism for heredity:
Passing of instructions for traits from parent to offspring
Mechanism – genes: sets of inherited instructions for making protein. Also, Deoxyribonucleic acid (DNA)= coded protein instructions.
3. Metabolism: acquire energy and materials
Sum of all chemical reactions carried out in an organ
2 Basic types: Anabolism: store energy in molecules
Catabolism: release energy from molecules
4. Homeostasis: Maintain stable internal conditions in spite of changes in external environment
5. Evolution (species, not individual):
Change in inherited traits of species over time.
Species: group of genetically similar organisms that can produce fertile offspring.
Process (natural selection)- environment – selects individuals with sets of traits that increase chances of survival and reproduction – adaptation.
6. Respond to stimuli- mechanisms:
Behavior- movement (usually self-directed) to maximize success.
Organisms are dependent on one another and their environment.
Results of long history of evolutionary adjustments.
8. Common set of macromolecules:
Carbohydrates: structure, energy storage
Lipids: energy storage, transport, cellular integrity
Proteins: metabolism/homeostasis, movement
Nucleic Acids: reproductions, heredity, and evolution.
Systematics: ID and classify according to specific characteristics
Why? Huge number of species- need to organize to make information manageable.
Artificial (not natural) way of organizing info, so changes regularly.
Taxonomy: process of naming
The old System--- (increasingly exclusive)
New System adds a Domain (Divided into 3 groups)
1. Archae: Prokaryotic: Non-nucleated single celled) “Recent” discovery, unusual biochemistry, unusual environments.
2. Bacteria: most familiar of Prokaryotes- most ubiquitous- found in all common environments.
3. Eukaryota: most familiar organisms
Nucleated, complex (eukaryotic) cells.
4 kingdoms: Animalia, plantae, Fungi, Protista.
Why not use common names?
Misleading- jellyfish, starfish, silverfish
May have more than 1 common name- panther, cougar, mountain lion, puma, catamount- all same organ
Same common name for different organs- gropher – ground squirrel
Modern Scientific Naming
2 word naming system: binomial nomenclature
Genus: contains similar species
Species: one particular kind of organ. Group of potentially or actually interbreeding organisms.
Scientific Naming Rules:
1. Number and order of words-2; genus, species
2. Language- latin- alphabet, words and grammar. (Chosen because dead language- doesn’t change)
3. Spelling- genus, capitalized; species, lower case.
4. Typed-italicized/ written- underlined.
5. Abbrev.- after 1st use, 1st letter of genus