Transcript Slide 1

Chapter 4 – The
Organization of
Life
The Kingdoms
 There are six (6):
 The first two are both single-celled, lack defined
nuclei, and reproduce by cell division
1. Archaebacteria- found in harsh environments
Thermophiles are found in
very hot places like hot
springs in Yellowstone
Methanogenes are found in swampy
methane producing places
The Kingdoms (cont.)
2. Eubacteria – very common
E.coli- found within the human
digestive system
Blue-green algae (cynobacteria)found in many types fresh water
Bacteria play a huge role in breaking down dead organisms and
recycling nutrients in the environment
The Kingdoms (cont.)
3. Fungi – have cell walls, are found on land, and
absorb their food. Along with bacteria fungi play a
huge role in breaking down dead organisms and
recycling nutrients to the environment.
The Kingdoms (cont.)
4. Protists - most are single-celled, but some are
not- most are found in water
Phytoplankton - can do photosynthesis and
include single celled and multicellular
organisms like diatoms and kelp – are more
plant like
Some protists are more
animal like and are
heterotrophicparamecium/amoeba
-many cause diseases
The Kingdoms (cont.)
5. Plants- contain a cell wall, are multicellular, one
of only two kingdoms to do photosynthesis to
produce its own food. (What is the other?)
The Kingdoms (cont.)
6. Animal - multicellular , has no cell wall, are found
in water and on land, are heterotrophic (ingest their
food)
Plants
 Lower order plants are the mosses and ferns
Mosses/Lichens
Ferns
Plants
 Higher order plants include gymnosperms
(conifers) and angiosperms (flowering plants).
Gymnosperm/Conifer have
specialized needle-like leaves and
bear their seeds in cones.
Angiosperms/Flowering plants
come in many forms and includes
most of the plants
humans and animals
use as food .
Animals
 Two major groups:
Invertebrates- have no spine (backbone)
 includes many classes of animal
 Insects are the most numerous and successful of all
types of animals because they are small, mobile, have a
waterproof exoskeleton and reproduce quickly
Animals
Invertebrates- also includes sponges, coral,
molluscs, and worms.
Animals
Vertebrates- animals that do have a spine
(backbone) include both ectothermic (cold-blooded)
and endothermic (warm-blooded) organisms
These ectothermic animals have a body
temperature that is the same as their environment.
Organization in an Ecosystem
 An ecosystem is composed of both biotic factors
(living) and abiotic factors (nonliving) and all are
connected.
Organized like this:
Organism species
population
community
ecosystem
Organism
 Any living thing.
Species
 A group of organisms that are so
closely related that they can mate and
produce fertile offspring.
Population
 All the members of the same species living in the
same place at the same time.
 remember that a population is defined only by its boundaries.
For example: A population of grasshoppers in a cornfield.
Community
 All of the different populations living at
the same place at the same time.
Ecosystem
 Includes all the members of the community
and all abiotic factors.
Sunlight
Precipitation
Soil
Habitat
 An organisms’ habitat is the type of ecosystem (or biome)
it lives in. It gets all the resources it needs here.
For example: Taiga- Coral Reef- Tropical rainforest
 Organisms are so well-suited for habitats through a
process of natural selection leading to evolution.
 This process occurs when an organism has some adaptation
(advantageous trait) that allows it to better survive and
reproduce passing on that trait.
 As this trait is passed on more and more (through reproduction)
it will eventually show in most members of the population. This
change in the characteristics of a population is Evolution.
The Theory of Evolution by Natural
Selection
 Has 5 major points:
1. All organisms have a greater reproductive potential
than is ever realized. More offspring are produced than
could possibly survive.
2. The environment is hostile and contains limited
resources.
3. Inherited variations exist. Some are advantageous,
some harmful. Variations are passed to offspring.
4. Those with advantageous traits are more likely to
survive.
5. Advantageous trait will be passed on in greater
frequency to subsequent generations.
Evolutionary Processes
 Convergent evolution – independent evolution of
similar structures (analogous) for similar purposes.
For example: Bird wings & insect wings show similarities
in structure
Evolutionary Processes (cont.)
 Co-evolution - process in which two species evolve in
response to one another.
For example:
Milkweed/Tussock Caterpillar
and
Crab/Sea snail
Evolutionary Processes (cont.)
 Artificial Selection - selective breeding by
humans for desired traits.
For example:
Different Dog Breeds
Evolution of Resistance
 An organism has a natural resistance to some chemical
or pathogen that allows it to survive. It then passes on
the gene for that trait until it shows in the entire
population.
For example:
Drug resistant strains
of Tuberculosis
Insects become resistant to
pesticides
The End