Introduction: The Science of Biology. Characteristics of Living Things Biology – the study of life. All life has 7 unifying characteristics: A. Cells.

Introduction: The Science of Biology

Characteristics of Living Things Biology – the study of life. All life has 7 unifying characteristics:

A. Cells (organization) 1. the basic building blocks of life

2. organelles – small structures that perform

specific functions w/in the cell

3. An organisms “body type” can be: a. unicellular – consists of a single cell b. multicellular – combine & functions together

“Cell Types”Prokaryotic -simple-no nucleus

Eukaryotic-complex-has a nucleus

B. Obtain & Use Energy 1. All organisms need to obtain & use large amounts of energy to fuel chemical reactions 2. Metabolism – the sum of all processes &

chemical reactions in an organism

3. What is the ultimate source of Energy? How is this energy utilized?

PhotosynthesisSUN

Heterotroph – need to consume food toobtain energy

Autotroph – produces its own food. Obtains its energy directly from the sun

C. Homeostasis1. the maintenance of internal conditions;

controlled by nervous system and hormones2. metabolism works only when internal

conditions are steady & stable

D. Response to Stimuli 1. homeostasis works only when organisms interact & respond to environment & surroundings

2. organisms must make proper adjustments in order to maintain homeostasis & regulate metabolism Ex. foraging, migration, sweating, shivering

E. Regulated Growth & Development

1. the end result of metabolism

2. Growth = increase in size Development = change & differentiation

3. carefully controlled growth leads to normal adult shape & function uncontrolled growth destroys life (ex. cancer)

F. Reproduction 1. necessary to produce offspring in order to continue the species

2. two kinds:

a. asexual – 1 parent; genetically identical offspring

(simply split in two; binary fission)

b. sexual – 2 parents; joining of an egg and sperm during fertilization. Get genetic variationDIVERSITY

G. Adaptation & Evolution

1. reproduction often involves genetic variation, organisms will inherit traits that enhance their survival & reproductive success in an environment

2. Natural selection chooses organisms that can “adapt” to changes so they can function; these organisms are more fit & likely to survive

“Survival of the Fittest”

3. SO, the diversity we see in life is a result of adaptaton organisms “change over time” and thus evolve…

* All living things share these 7 basic characteristics

* This unity suggests that all life descended from a common ancestor.

* However, the diversity of life suggests that the evolution from this common ancestor has been a Descent with Modification making adaptations to different environments and ways of life

Why Do We Classify Organisms? Biologists group organisms to represent

similarities and proposed relationships. Classification systems change with

expanding knowledge about new and well-known organisms.

Placing organisms into domains and their subdivisions is a classification scheme that indicates the evolutionary relationships of the organisms being studied.

Helpful to have a universal system to group these organisms.

Tacitus bellus

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II. Classification of Living Things

Leucaena leucocephala Lead tree

ClassificationTaxonomy

discipline to classify organisms according to similar features and assign each organism a universally accepted name

Binomial NomenclatureTwo part name (Genus, species)

Hierarchical ClassificationSeven Taxonomic Categories

(DKPCOFGS)

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Carolus von Linnaeus(1707-1778)

Swedish scientist who laid the foundation for

modern taxonomy

Binomial NomenclatureCarolus von Linnaeus Two-word naming systemHomo sapiens

Genus (Homo)Noun, Capitalized,

Underlined or ItalicizedSpecies (sapiens)

Descriptive, Lower Case, Underlined or Italicized

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Hierarchical ClassificationTaxonomic categories

Domain DashingKingdom KingPhylum PhilipClass CameOrder OverFamily ForGenus GreenSpecies Soup

Organisms can only be members of thesame species of they can reproduce w/each other to produce fertile offspring

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Taxonomic

Classification

Blue Tang Yellow Tang

Kingdom Animalia Animalia

Phylum Chordata Chordata

Class Actinopterygii Actinopterygii

Order Perciformes Perciformes

Family Acanthuridae Acanthuridae

Genus Paracanthurus Zebrasoma

Species P. hepatus Z. flavescens

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Taxonomic

Classification

Blue Tang Percula Clownfish

Kingdom Animalia Animalia

Phylum Chordata Chordata

Class Actinopterygii Actinopterygii

Order Perciformes Perciformes

Family Acanthuridae Pomacentridae

Genus Paracanthurus Amphiprion

Species P. hepatus A. percula

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Taxonomic

Classification

Blue Tang Great White Shark

Kingdom Animalia Animalia

Phylum Chordata Chordata

Class Actinopterygii Chondrichthyes

Order Perciformes Lamniformes

Family Acanthuridae Lamnidae

Genus Paracanthurus Carcharodon

Species P. hepatus C. carcharias

Ex. Human Taxonomy

Domain:Kingdom:Phylum:Class:Order:Family:Genus:Species:

Eukarya (has a nucleus)Animalia (multicelluar heterotroph)Chordata (have a backbone)Mammalia (have hair, mam. glands)Primates (large brains; intelligent)Hominidae (walk upright on 2 legs)

Homo (man)sapiens (wise)

Kingdoms and Domains

Bacteria Archaea Eukarya

Bacteria Archaea Protista Plantae Fungi Animalia

Monera Protista Plantae Fungi Animalia

The three-domain system

The six-kingdom system

The traditional five-kingdom system

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(prokaryotes)

NO LONGER USED

Eubacteria•Prokaryotic•Unicellular•Cell Wall with peptidoglycan •Autotrophic (photosynthesis or chemosynthesis) or Heterotrophic•Can be beneficial or pathogenic

Archaebacteria•Discovered in 1983

•Scientists took samples from a spot

deep in the Pacific Ocean where hot

gases and molten rock boiled into the

ocean form the Earth’s interior.  

•Prokaryotic cells

•unicellular

•Contain adaptations to extreme

environments (Lack of oxygen,

extreme temps, high acidity)

•Autotrophic or Heterotrophic

•Cell wall (NO peptidoglycan)

Domain Eukarya contains….Kingdom Protista

Kingdom Fungi Kingdom Plantae 

Kingdom Animalia

ProtistaEukaryotic“mis-fits” do not fit the definition of a plant, animal, or fungi.Algae, protozoans, and slime molds Unicellular

A few exceptions: Some are multicellular (algae)

Some have cell walls, not all

PlantaeEukaryoticMulticellularCell walls that contain celluloseAutotrophic

photosynthesismosses, ferns, conifers, and flowering

plants

FungiEukaryotic Mostly multicellular

Exception: yeast is unicellularHeterotrophic

Decomposers – break down

dead organisms and absorb their foodCell Wall composed of chitinYeast, mold, mushroomsNot capable of photosynthesis

Animalia

EukaryoticMulticellularNO cell wallHeterotrophic

Interesting Animals!

III. Organization of Living Things A. - basic building blocks of matter

B. - atoms bonded togetherC. - basic building block of lifeD. - similar cells performing similar function (ex. Nervous/Brain)E. - different tissues work together (ex. muscle/nervous tissue make up skin)F. - organs working together (ex. stomach, intestines digestive sys.) G. Organisms -- unicellular organisms use organelles

Atoms Molecules

CellsTissues

Organs

Organ system

H. Groups of Organisms 1. – same species living in a particular place at a particular time

2. – different populations that live in same area & interact 3. – a community of living things & the physical env’t4. – groups of ecosystems in a large geographic area 5. – all organisms & their supportive env’ts on the planet

Population

Community

Ecosystem

Biome

Biosphere