Transcript Characteristics of Life/Taxonomy PPT

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?
SUN
How is this energy utilized? Photosynthesis
Autotroph – produces its own food.
Obtains its energy directly from the sun
Heterotroph – need to consume food to
obtain energy
C. Homeostasis
1. the maintenance of internal conditions; controlled
by nervous system and hormones
2. 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 variationDIVERSITY
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
II. Classification of Living Things
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.
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Tacitus bellus
Classification
 Taxonomy
 discipline to classify organisms according to
similar features and assign each organism a
universally accepted name
 Binomial Nomenclature
 Two part name (Genus, species)
 Hierarchical Classification
 Seven Taxonomic Categories (DKPCOFGS)
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Leucaena leucocephala
Lead tree
Binomial Nomenclature
 Carolus von Linnaeus
 Two-word naming system
 Homo sapiens
 Genus (Homo)
 Noun, Capitalized,
Underlined or Italicized
 Species (sapiens)
 Descriptive, Lower Case,
Underlined or Italicized
BioEd Online
Carolus von Linnaeus
(1707-1778)
Swedish scientist who laid
the foundation for modern
taxonomy
Hierarchical Classification
 Taxonomic categories
 Domain
 Kingdom
 Phylum
 Class
 Order
 Family
 Genus
 Species
Dashing
King
Philip
Came
Over
For
Green
Soup
Organisms can only be members of the
same species of they can reproduce w/
each other to produce fertile offspring
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
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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
The three-domain system
Bacteria
Archaea
Eukarya
(prokaryotes)
The six-kingdom system
Bacteria
Archaea
Protista
Plantae
Fungi
Animalia
Plantae
Fungi
Animalia
The traditional five-kingdom system
Monera
Protista
NO LONGER USED
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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
Protista
 Eukaryotic
 “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
Plantae
 Eukaryotic
 Multicellular
 Cell walls that contain cellulose
 Autotrophic
 photosynthesis
 mosses, ferns, conifers, and flowering plants
Fungi
 Eukaryotic
 Mostly multicellular
 Exception: yeast is unicellular
 Heterotrophic
 Decomposers – break down
dead organisms and absorb their food
 Cell Wall composed of chitin
 Yeast, mold, mushrooms
 Not capable of photosynthesis
Animalia
 Eukaryotic
 Multicellular
 NO cell wall
 Heterotrophic
Interesting Animals!
III. Organization of Living Things
A. Atoms - basic building blocks of matter
B. Molecules- atoms bonded together
C. Cells
- basic building block of life
D. Tissues - similar cells performing
similar function (ex. Nervous/Brain)
E. Organs - different tissues work together
(ex. muscle/nervous tissue make up skin)
F. Organ system - organs working together
(ex. stomach, intestines  digestive sys.)
G. Organisms
-- unicellular organisms use organelles
H. Groups of Organisms
1. Population – same species living in a
particular place at a particular time
2. Community – different populations that
live in same area & interact
3. Ecosystem – a community of living things
& the physical env’t
4. Biome – groups of ecosystems in a large
geographic area
5. Biosphere – all organisms & their supportive
env’ts on the planet