Chapter 1: Introduction: Themes in the Study of Life

Evolution
The process of change that has transformed life on Earth from its earliest beginnings to the diversity of organisms living today.

Biology
The scientific study of life.

Properties of life
– order
– evolutionary adaptation
– response to the environment
– reproduction
– growth and development
– energy processing
– regulation

Themes
– New Properties Emerge at Each Level in the Biological Hierarchy
– Organisms Interact w/ Other Organisms and the Physical Environment
– Life Requires Energy Transfer and Transformation
– Structure and Function Are Correlated at All Levels of Biological Organization
– The Cell Is an Organism’s Basic Unit of Structure and Function
– The Continuity of Life is Based on Heritable Information in the Form of DNA
– Feedback Mechanism Regulate Biological Systems
– Evolution, the Overarching Theme of Biology

Levels of Biological Organization
1. Biosphere
2. Ecosystems
3. Communities
4. Populations
5.Organisms
6. Organs and Organ Systems
7. Tissues
8. Cells
9. Organelles
10. Molecules

Biosphere
All life on Earth and all the places where life exists

Ecosystems
All the living things in a particular area, long with all the nonliving components of the environment with which life interacts

Communities
Organisms inhabiting particular ecosystem

Population
All the individuals of a species living within the bounds of a specified area

Organisms
Individual living things

Organs and Organ Systems
– A body part that carries out a particular function in the body
– Each a team of organs that cooperate in a larger function

Tissues
A group of cells that work together, performing a specialized function

Cells
Life’s fundamental unit of structure and function

Organelles
The various functional components present in cells

Molecules
Chemical structure consisting of two or more small chemical units called atoms

Emergent Properties
Properties that are not present at the preceding level
They are not unique to life

Systems Biology
An approach to attempt to model the dynamic behavior of whole biological systems based on a study of the interactions among system’s parts

Global climate change
Global warming

Eukaryotic Cell
– All other forms of life, including plants and animals, are composed of eukaryotic cells
– They are subdivided by internal membranes into various membrane-enclosed organelles

Prokaryotic Cell
– Simpler and smaller than eukaryotic cells
– The DNA is not separated from the rest of the cell by enclosure in a membrane-bounded nucleus

DNA
– DeoxyriboNucleic Acid
– Substance of genes

Genes
The units of inheritance that transmit information from parents to offspring

Gene Expression
The entire process, by which the information in a gene directs the production of a cellular product

Genome
The entire “library” of genetic instructions that an organism inherits

Genomics
The study of whole sets of genes of a species as well as comparing genomes between species

Bioinformatics
The use of computational tools to store, organize, and analyze the huge volume of data that result from high-throughput methods

Negative feedback
An accumulation of an end product of a process slows that process

Positive feedback
An end product speeds un its own production

Bacteria
Prokaryotic cells

Archaea
Prokaryotic cells

Eukarya
All the eukaryote (organisms with eukaryotic cells) grouped in this domain, which includes kingdoms Plantae, Fungi, and Animalia

Natural Selection
The natural environment “selection” for the propagation of certain traits among naturally occurring variant traits in the population

Science
The way of knowing; an approach to understanding the natural world

Inquiry
The search for information and explanation

Data
Recorded observations

Inductive reasoning
Type of logic in which collecting and analyzing observations can lead to important conclusions

Hypothesis
A tentative answer to a well framed question- an explanation on trial

Deductive reasoning
A generally used after the hypothesis bas been developed and involves logic that flows in the opposite direction, from the general to the specific

Controlled experiment
One that is designed to co;pare an experimental group with a control group

Theory
A much broader in scope that a hypothesis; generally enough to spin off many new, specific hypothesis that can be tested; generally supported by a much greater body of evidence

Model organism
A species that is easy to grow in the lab and lends itself particularly well to the questions being investigated

Technology
Generally applies scientific knowledge for some specific purpose