Bio exam 1

Biology

• The scientific study of life

• A wide scale of size

• A huge variety of life both past and present

Biosphere

The sum of all living organisms on earth and their environment

Ecosystem

The relationships of a smaller group of organisms and their environment

Ecosystem

• Each organism interacts continuously with its environment

• Organism interacts continuously with the living and nonliving factors in environment

• All the living organisms in a specific area, along with all of the non living factors with which they interact, form an ecosystem

Darwin view of life

The evolutionary view of life came into focus in 1859 when Charles Darwin published on the origin of Species by means of natural life

Darwin’s theory of evolution

All organisms are connected through the tree of life meaning that all organisms are evolved from a common ancestor

Darwin’s book two main points

1. Species living today descended from a succession of ancestral species in what Darwin called”descent with modification,” capturing the duality of life’s (unity descent) and (diversity modification)

2. Natural selection is the mechanism for descent with modification

Evolution

Mutations in DNA that allows organisms to survive

Process of change over time

Adaption

Is a new characteristic in an organization that allows it to survive in a new environment

Natural selection

Process by which organisms adapt to their new environment

• Darwin was struck by the diversity of animals on the Galápagos Islands.

• He thought that adaptation to the environment and the origin of new species were closely related processes

• As populations separated by a geographic barrier adapted to local environments, they became separate species

Taxonomy

The branch of biology concerned with identifying,naming, and classifying species

• It formalizes the hierarchical ordering of organisms into broader and broader groups.

Six kingdoms

1. Eubacteria

2. Archaebacteria

3. Protista

4. Fungi

5. Plantar

6. Animalia

Three domains

Prokaryotic

Archaea

Eukaryotic

Prokaryotic

• eubacteria

• Bacteria and Archaea have prokaryotic cells

• simpler and usually smaller and characteristic of bacteria.

• Do not have a nucleus inside their cell

• All unicellular

Eukaryotic

• Eukarya have eukaryotic cells

• Protista, fungi, plantar, animalia

• Most plants, fungi, and animals are multicellular, Protists are generally single-celled

• Have their genetic materials enclosed in a nucleus inside their cells

• Multicellullar(mostly), unicellualr(some)

Archaea

Are organism that look like bacteria on the surface but like eukaryotes on the inside

Are also organisms that live in the extreme environments

Live at low pH to acidophiles (acid environment)

Live at high concentration- halophiles

Live at high temperatures- hyperthermophiles

Live without oxygen- methanogens

Level of organization

Individual- an organism can be unicellular or multicellular

Organ systems- group of ells, tissues and organs that have specific function (ex:digestive system)

Organ- group of cells and tissues that ave an overall function (ex: heart, lung, stomach)

Tissues- group of cells performing a specific function (ex: tissues of small intestine)

Cells- unit of life (ex: stomach cells)

In this order

Scientific method

1. Observation

2. Hypothesis

3. Experimentation

4. Conclusion

Observation

A change in an ecosystem

Hypothesis

Possible reasons for change that need to be tested

Experiment

Testing the hypothesis

Conclusion

Analysis of the results to prove/disaprove the hypothesis

Scientific theory

Is a hypothesis that has been proven to be correct over time. (Ex: all organisms made of cels. Cell is the unit of life.)