Life
Reagan McNeely
The Characteristics of Living Things 9.1
All living things have a cellular organization, contain similar chemicals, use energy, respond to their surroundings, grow and develop, and reproduce.
Life Comes From Life
Living things arise from living through reproduction.
The Needs of Living Things
All living things must satisfy their basic needs for food, water, living space, and stable internal conditions.
Why Do Scientists Classify? 9.2
Biologists use classification to organize living things into groups so that the organisms are easier to study.
The Naming System of Linnaeus
The naming system of Linnaeus is so that scientist can name a living thing and the name have something to do with that animal.
Levels of Classification
The more classification levels that two organisms share, the more characteristics they have in common.
Taxonomic Keys
Taxonomic keys are useful tools for determining the identity of organisms.
Evolution and Classification
Species with similar evolutionary histories are classified more closely together.
Domain Bacteria 9.3
Some domain bacteria is good for you but some is not.
Domain Archaea
Although bacteria and archaea are similar in some ways, there are important diferences in the structure and chemical makeup of their cells.
Domain Eukarya
Scientists classify organisms in the domain Eukarya into one of four kingdoms: protists, fungi, plants, or animals.
The Atmosphere of Early Earth 9.4
On ancient Earth, nitrogen, water vapor, carbon dioxide, and methane were probably the most abundunt gases in the atmosphere.
The First Cells
Scientists hypothesize that the small chemical units of life formed gradually over millions of years in Earth's waters. Some of these chemical units joined to form the large chemical building blocks found in cells. Eventually, some of these large chemicals joined together and became the forerunners of the first cells.