1. Inquiry into Life Eleventh Edition Sylvia S. Mader
Chapter 1
Lecture Outline
Prepared by: Wendy Vermillion Columbus State Community College
Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. 1.1 The Characteristics of Life
Living things share the following characteristics in common:
High degree of organization
Require input of energy and materials
Reproduce
Respond to stimuli
Are homeostatic
Undergo growth and development
Adapt to their environment

3. The Characteristics of Life cont’d.
Living things exhibit levels of biological organization
Cellular level
Tissue level
Organ level
Organ system level
Organismal level

4. Levels of biological organization
Fig 1.2

5. The Characteristics of Life cont’d.
Organisms require materials and energy
Energy-capacity to do work
Photosynthesizers use light to make food
Animals ingest food
Food molecules yield energy

6. Living things acquire materials and energy, and they reproduce
Fig 1.3

7. The Characteristics of Life cont’d.
Living things reproduce
DNA contains hereditary information
Genes in DNA molecules allow organisms to reproduce
Single-celled organisms reproduce asexually by dividing
Daughter cells are genetically identical
Multicellular organisms reproduce sexually
Each parent contributes one half of genes to offspring
Offspring are genetically unique

8. The Characteristics of Life cont’d.
Organisms respond to stimuli by moving toward or away from the stimulus
Movement toward the stimulus is called a positive response
Movement away from the stimulus is called a negative response
Movements are important components of behavior
Behaviors are protective and adaptive

9. The Characteristics of Life cont’d.
Living organisms are homeostatic
Homeostasis- all processes in an organism that maintain a stable internal environment
All organ systems function in homeostasis

10. The Characteristics of Life cont’d.
Living things undergo the processes of growth and development
Growth- characterized by an increase in size and cell number
Development- all events occurring between conception and death

11. Living things grow and develop
Fig 1.4

12. The Characteristics of Life cont’d.
Living organisms adapt to the environment
Adaptations- specific characteristics that increase survival
Evolution- process by which species change over time
new variations within a species may have a survival benefit
Those individuals survive to reproduce

13. The Characteristics of Life cont’d.
Adaptation, cont’d.
Evolution can explain both unity and diversity of organisms
All organisms share characteristics of life
Share common ancestry
Diversity results from adaptations to different environments

14. 1.2 Classification of living things
Taxonomy- discipline of identifying and classifying organisms
Organisms classified into taxons
Species-most specific grouping
Genus- related species
Family- related genera (plural form of genus)
Order-related families
Class- related orders
Kingdom- related kingdoms
Domain-the most general grouping of related kingdoms

15. Classification of humans
Table 1.1

16. Classification of living things cont’d.
Domain- most general and largest taxon
Based on biochemical evidence
Archae-unicellular prokaryotic organisms which live in extremely harsh environments
Bacteria-unicellular prokaryotes found in nearly all environments
Eukarya- unicellular and multicellular organisms which have DNA contained within a nuclear membrane

17. Pictorial representation of the three domains of life
Fig 1.5

18. Classification of living things cont’d.
Kingdoms
Archae and Bacteria- currently under revision
Eukarya- divided into the 4 kingdoms
Protista- unicellular and multicellular organisms; some photosynthetic, others are heterotrophic
Fungi- heterotrophic plant-like organisms
Plantae- multicellular photosynthetic green plants
Animalia- multicellular heterotrophic animals

19. Classification of living things cont’d.
Binomial nomenclature
Each organism is given a scientific name which will be recognized by all scientists
Based on Latin
Consists of an organism’s genus and species
The genus is capitalized and the species is lower-case
The entire name is either underlined or printed in italics
Example: the scientific name of humans is Homo sapiens

20. 1.3 Organization of the biosphere
Biosphere- zone of air, land, and water at Earth’s surface which supports life
Population-all members of a species living in an area
Community-groups of populations living together
Ecosystem-includes communities and the physical environment (soil, air, water) in an area

21. A grassland, a terrestrial ecosystem
Fig 1.6

22. Organization of the biosphere cont’d.
Chemical cycling- chemicals cycle through an ecosystem until they are returned to the environment through death and decomposition
Energy cycling-flows from the sun through photosynthesizers to others in food chain and dissipates back to the environment as heat
Climate determines location of ecosystems
The most diverse ecosystems form where solar energy is greatest

23. Organization of the biosphere cont’d.
Human populations- modify the environment rather than adapt
We rely on healthy ecosystems to cycle chemicals through the biosphere, and for many foods and medicines
In order for an ecosystem to remain healthy it must remain biologically diverse
The impact of human population growth on coral reefs and tropical rainforests has been particularly tremendous
Human activities have destroyed 10% of all reefs and have seriously degraded 30% in the past few decades
Rainforests are being clear cut for agricultural land

24. Biodiversity
Biodiversity is a reflection of the total number of species, the genetic variability they contain in their genes, and the environments in which they live
Present biodiversity of Earth is estimated to be 15 million species (only 2 million currently identified!)
Extinction rate- currently about 400 species per day lost
Preservation of ecosystems must be of primary importance to ensure our survival and the survival of all living organisms

25. A coral reef, a marine ecosystem
Fig 1.7

26. 1.4 The process of science
The scientific method is an orderly process of exploring natural phenomena
It consists of a series of steps
Identification of a problem through observation
Formulation of a hypothesis
Experimentation and collection of data
Development of a conclusion
May lead to a scientific theory

27. Flow diagram for the scientific method
Fig 1.8

28. Scientific method cont’d
Observations- nature is orderly and measurable and natural laws do not change
Scientists use all senses for observation, and extend capabilities through instrumentation
Hypothesis
Use of inductive reasoning to formulate a possible explanation for a natural event
Experimentation
Deductive reasoning used to determine how to test the hypothesis
Experimental design- ensures scientist is testing what he/she wants to test for and that meaningful results will be obtained
Control group-goes through all aspects of experiment but lacks factor being tested
Experimentation using a model-results are considered hypotheses until tested further on actual subjects

29. Scientific method cont’d.
Data-results of experiment
Must be observable and objective
Conclusion
Formulated from analysis of data
May suggest further experiments are necessary
Reported in scientific journals so methods are available to other scientists
Results must be repeatable
For an excellent illustration of the process, refer to pg of your text

30. Scientific theory
Scientists seek to explain the natural world through scientific theories
Supported by many experiments and observations
Theories are accepted by scientists throughout the world

31. Science and social responsibility
Technology-application of scientific knowledge
practical purpose
Most technologies have both positive and negative effects
responsibility of all people to make decisions about which technologies should be used and which should not
decisions may be made at the voting booth
Education is imperative