Chapter One

The Scope of Biology

Global to Microscopic• Bio = Life Ology = the study

• Biology – natural science that is the study of living things on a global scale of the entire planet down to the microscopic world

Large to Small

•Biosphere – all the parts of the planet that are inhabited by living things (land, water, atmosphere)

• Ecosystem – community of living things and the environment that supports them (plants, animals, air, water, and sunlight)

–Ecosystems are very diverse and dynamic (changing)

Desert Marsh Pond Rainforest

–All ecosystems combined make up the biosphere

Large to Small• Organism – Individual living

thing

–Different types of organisms within their environment make up an ecosystem

• Cell – basic units of structure and function within an organism

–Organisms are made up of one or more cells

•Unicellular – single cell

•Multicellular – many cells

Large to Small• DNA and Genes

–DNA – molecule responsible for inheritance• Instructs cell to make all important molecules

–Gene - hereditary segment for a single trait

Life’s Diversity• Life is very diverse; it contains

thousands of different species

–Species – a distinct form of life

• Insects are the most diverse group of animals

Canis familiaris Canis lupus

Classification

• Classification is needed because life is so diverse and there are so many different kinds of organisms

–Classification – organizing similar species into larger groups

The Three Domains of Life

• Domain – Broadest category of classification

–Archaea

–Bacteria

–Eukarya

The Three Domains of Life

• Kingdoms – category of classification after domains

–4 kingdoms within Eukarya domain

• Animals, Plants, Fungi, Protists

–1 kingdom within Archaea domain

• Archaebacteria

–1 kingdom within the

–Bacteria domain

• Eubacteria

The Three Domains of Life• Archaea and

bacteria domains contain very small and simple organisms; unicellular and prokaryotic cells–Prokaryotic – cells without nuclei

• The Eukarya domain contains more complex organisms; most are multicellular and have eukaryotic cells

–Eukaryotic – cells with a nuclei

Ten Unifying Themes of Life• 1. Biological Systems

• System – complex organization formed from a simpler combination of parts

–Made up of levels

of organization

• Atom-molecule-cell-tissue-organ-organ system- Organism

• Applies to all levels of life: Biosphere – cells

Ten Unifying Themes of Life• 2. Cellular Basis of Life

–All living things are made up of cells and have levels of

organization.

Ten Unifying Themes of Life

• 3. Form and Function

–Form is unique to its function

•Ex. The shape of a bird’s wings = fly

•Nerve cell has long fibers = send messages

Ten Unifying Themes of Life• 4. Reproduction and Inheritance

– Inheritance is passed through reproduction

– Genes contain DNA which carries information for certain characteristics

– During cellular division, DNA is copied– Egg (mom DNA) fuses with sperm (dad

DNA)• Creates individual with• some inherited traits

Ten Unifying Themes of Life• 5. Interaction with the

Environment–All organisms interact with its environment•Photosynthesis-process by which plants make food)–We depend on oxygen

Cellular respiration – process by which animals use food to create energy

Plants depend on carbon dioxide

Ten Unifying Themes of Life• 6. Energy and Life

–All life processes require energy•Energy - the ability to do work

–Energy flow within and ecosystem

–Sunlight – producers - consumers•Energy then exits as heat

–Producers (autotrophs) - produce own food

–Consumers (heterotrophs) – organisms that can not make their own food and depend on other autotrophs or heterotrophs

Ten Unifying Themes of Life

• 7. Regulation

–Homeostasis - the ability of an organism to keep conditions inside the body constant

•(sweating,

•shivering)

Ten Unifying Themes of Life• 8. Adaptation and Evolution

–Living things adapt

•Adaptation - any characteristic

or change that

helps the organism

survive or live successfully in its environment

•Population – localized group of organisms belonging to the same species

•Natural Selection - process by which individuals that are better adapted to their environments survive and reproduce more successfully than less well adapted individuals do

Evolution – change through time

Ten Unifying Themes of Life• 9. Biology and Society

–Biology is everywhere in society

Why is Biology important?

–1. Medicine (Avian Bird Flu)

–2. Agriculture (Growing genetically engineered food)

–3. Industry (Use of bacteria to break down sewage: efficiency)

Ten Unifying Themes of Life• 10. Scientific Inquiry

–Because Biology is a science, there is a reliance on certain processes of inquiry

–Scientific Method - an organized approach to help understand how the natural world works