Introduction into General Biology

Dr. Cory L. BlackwellAugust 25, 2015

What is Biology????

• Bio- (life)……..-ology (study of)

• Biology is the fundamental study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy

• Biology is a broad field of science– Can you name some of these subdivisions?

• Subdivisions of biology are recognized on the basis of the scale at which organisms are studied– Biochemistry examines the basic chemistry of life– Molecular Biology studies the interactions of the systems

of biological molecules– Cellular Biology studies the basic building block of life,

the cell.– Physiology examines the physical and chemical functions

of tissues and organ systems– Ecology examines how various organisms interact with

one another and with the environment

*List is not all-inclusive*

Contributors to the Field of Biology

• Hippocrates (Greek Physician)– “Father of Western Medicine”

• Anton von Leeuwenhoek (Dutch Scientist)– “Father of Microbiology”

• Gregor Mendel (Moravian Monk/Scientist)– “Father of Genetics”

• Charles Darwin (English Geologist)– “Father of Evolution”

• Francis Crick and James Watson (Rosalind Franklin)– Deciphered the structure of DNA

Three States of Being

• Living

• Dead

• Non-living

Living, Dead or Non-Living????

Living, Dead or Non-Living????

Living, Dead, or Non-Living

Living, Dead or Non-Living????

Seven Characteristics of Life

1. Cellular Organization—all living organisms consist of one or more cells

2. Ordered Complexity—Living organisms contain many complex molecular structures and systems that are highly ordered

3. Sensitivity—living things all react or respond to stimuli.

4. Growth, Development, and Reproduction—all organisms are capable growing and reproducing. Through reproducing they pass on genetic material to their offspring

5. Energy Utilization—all living things use energy to live and grow

6. Homeostasis—All organisms maintain relatively constant internal conditions that are different from their environment

7. Evolutionary Adaptation—all organisms interact with other organisms and their environment in ways that influence their survival. – “Survival of the Fittest” or “Only the Strong

Survive”– http://www.nature.com/scitable/topicpage/evolut

ionary-adaptation-in-the-human-lineage-12397– “Survival of the Sickest” by Sharon Moalem

Living, Dead or Non-Living????

Influenza A Virus

Hierarchical Organization

• The organization of the biological world is arranged from smallest to largest. – Each level builds on the level below it (upside

down pyramid)

• There are five levels of hierarchical organization

1. Cellular Level

• At the cellular level, atoms interact to form molecules.

• Complex biological molecules are assembled into organelles.– Organs of a cell

• Organelles are contained within membrane-bound units called cells.

2. The Organismal Level

• Cells, in complex multi-cellular organisms, exhibit different levels of organization– Tissues

• Groups of similar cells that acts as a functional unit

– Organs• Body structures composed of several different tissues

– Organ systems• Multiple organs that work together to complete a function

– Organism• Comprised of the different organ systems working together

3. The Population Level

• Individual organisms can be categorized into several hierarchical levels in the living world– Species

• A particular kind of organism form a species (humans)

– Population• Group of organisms of the same species living in the same

place (humans in Clermont)

– Biological Community• Consists of all the populations of DIFFERENT species living

together in the same environment (all living organisms in Clermont)

4. Ecosystem Level

• The biological community AND the physical habitat (non-living) that the community lives is known as an Ecosystem– Swamps– Deserts– Jungles

5. The Biosphere

• The combination of all ecosystems

• The planet Earth is a Biosphere

• Reductionism—principle of trying to understand a complex system by examining its simple components

Classification and Identification of Life

• Diversity is the hallmark of life– 1.8 million species have been identified– Group organisms according to their similarities

• What drives this diversity????

• DNA analysis divide all organisms into 3 domains– Eukaryotes, Bacteria, and Archaea

• Bacteria and Archaea make up the group Prokaryotes

Taxonomy

Taxonomy—the science of classifying organisms (taxa—categories of organisms)

• Provides a reference for identifying organisms

• Carlos Linnaeus introduced a formal system of classification– Used Latin names to provide a “common”

language for all organisms

Figure 10.1 The Three-Domain System.

BacteriaMitochondria

Cyanobacteria

Chloroplasts

Thermotoga

Gram-positivebacteria

Proteobacteria

Horizontal gene transferoccurred within thecommunity of early cells.

Nucleoplasm grows larger

Mitochondrion degenerates

Giardia

Euglenozoa

Diatoms

Dinoflagellates

Ciliates

AnimalsFungi

Amebae

Slime molds

Plants

Greenalgae

Eukarya

Extremehalophiles

Methanogens

Hyperthermophiles

Origin of chloroplasts

Origin of mitochondria

Archaea

Vertical Gene TransferLateral Gene Transfer

Scientific Nomenclature

• Common names– Vary with languages and with geography– Spanish Moss • Tillandsia usneiodes

• Binomial nomenclature (genus + specific epithet)– Used worldwide– Genus capitalized and species lowercase • Escherichia coli and Homo sapiens

Taxonomic HierarchyDomain

KingdomPhylum

ClassOrder

FamilyGenus

Species

What is Science?

• Science is concerned with developing an increasingly accurate understanding of the world around us using both observation and reasoning– Inquiry—search for information and explanations of

natural phenomena– Data—recorded observations

• Qualitative or Quantitative

• Two types of reasoning1. Deductive Reasoning2. Inductive Reasoning

Deductive vs. Inductive Reasoning

• Deductive starts as a general statement and examines possibilities to reach a conclusion (general to specific)– All men are dogs. Dwayne Johnson is a man. Dwayne

Johnson must be a dog.

• Inductive makes broad generalizations based on specific observations (specific to general)– Shakira is a great dancer. Shakira is Colombian. All

Colombians are great dancers.– Also known as Inference

Scientific Method

• Every scientific discipline is governed by the scientific method.

• Defined as the body of techniques utilized in investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge

• Five steps to the scientific method

5 Steps of the Scientific Method

1. Present a questionWhy did my car not start this morning?

2. Form a hypothesis—a conjecture or belief based on already established information

The car did not start because the battery is “dead”.

3. Make a predictionIf I get a new battery the car will start.

5 Steps of Scientific Method

4. Test your hypothesis (Experiment)Purchase a new battery from Autozone, replace the battery, turn the ignition.

5. Observe results and make an analysisDid the car start? If not, then form another hypothesis

“Control vs. Experimental”Control Experiment have pre-established outcomesand

are used to validate the experimentIndependent vs. Dependent variable