Download Science 9 Notes_1

February 4, 2013
Science 9
Four main purposes for adaptations
1. Protection from predators- example: an organism that is able to camouflage itself to protect
itself from predators.
2. Protections from the Elements or Environment- example: Camels have three eye lids to protect
its eyes from sand.
3. Obtaining Food- Example: Roots in plants adapt, reach and spread out to increase surface area
so they can absorb more nutrients which mean obtaining more food.
4. Locomotion- example: fish having fins or Ducks having webbed feet.
Feb 7, 2013
Classification of Organisms
We classify organisms so that we can study them. This also allows us to communicate properly with
other scientists throughout the world (common language). This is called Taxonomy
Aristotle came up with the first classification system for animals in 384BC. His system had 3 categories
1. Land Dwellers
2. Air Dwellers
3. Water Dwellers
Linnaeus came up with the modern classification system that we still use today. It is a hierarchical
classification system built with 7 levels.
1. Kingdom- Most general category (largest number of organisms) 5 Kingdoms
 Animalia
 Plantae
 Fungi- mushrooms
 Protista- multi celled organisms
 Monera- 1 celled organisms ex. bacteria
2. Phylum
3. Class
4. Order
5. Family
6. Genus
7. Species- Most specific ( 6 million different species)
This is based on structural adaptations and similarities. This system gives us the scientific name of
every organism in the world. It uses binomial nomenclature (two name system). This is the Genus
and Species name of the organism.
Example- Canada Goose scientific name Branta cahadensis
l
l
V
V
(Genus capitalized)
(Species Lower case)
Interactions between organisms
Feb.8, 2013
Ecosystems -> Species
Ecosystems- Areas where biotic and abiotic factors mix. Example: Tundra, pond, rainforest.
Biotic- Living
Abiotic- Non living
Ecosystems from the far north to near the equator as well as land base (terrestrial) to water based
(aquatic). When ecosystems have extreme conditions, the number and variety of organisms decrease.
The artic has leas and diversity and the rain forest has the greatest diversity. Terrestrial ecosystems have
the greatest number of insects and lower organisms in the food chain.
Teritary consumers (- numbers)
Secondary consumers
<- Food Chain
Primary consumers
Trophic Levels
Feeding Levels
Producers (+ numbers)
Communities- These are areas or places where different species interact. Example: deer, wolves
When scientists examine communities to see how healthy they are, they will count the population of
different species.
Population- Number of one species in an area.
Scientists can then compare the health of communities and ecosystems using the diversity index
calculation. DI = # OF RUNS divided by TOTAL SPECIES
A run is a number of the same species before another species is found.
A higher diversity index indicates a healthier ecosystem.
Topic 2- Habitat and lifestyle
No species can survive on itself/own. It is part of a food web or chain. There is on interdependence
between all living things in an environment. Every organism has its Niche. This is the role an organism
plays in its environment. It includes where it lives and what it does. Example: Niche of a wolf- liv in trees
mountain areas, predator for smaller animals.
There are two types of Niches:
1. Broad Niche (generalists) - Live in a wide variety of areas because they can handle a wide variety of
conditions and have a wide variety of food sources.
2. Narrow Niche (specialists) - Organisms that are adapted for a specific area, specific conditions, or
specific food resource.
Interdependence
1. Predator/ prey- Balance
As the population of one organism changes, the other will follow suit soon.
2. Symbiotic Relationships
Mutualism- both organisms benefit from the relationship. Example- bees and flowers
Paraitism- involves host and parasite. Parasite benefits and the host is harmed. Example:
humans and leeches.
Commensilism- one organism benefits and the other organism is unaffected. Example: birds
nesting in trees.
Feb. 11, 2013
Competition
1. Inter species Competition- Competition between two or more different species. This is a
relationship in which neither really benefits. The resources that compete for may or may not be
enough for both to survive. Sometimes organisms can coexist and lesson the competition
through resource partitioning ( some organisms use only “pieces” of this environment).
Example: Giraffes and Zebras
2. Intra species Competition- Competition within a species ( breeding/ reproduction)
Natural Selection- This is when nature decides which combination of traits are most favorable.
Only organisms with favorable traits will survive long enough to reproduce and pass on these
traits. AKA Survival of the fittest.
Artificial Selection- AKA Selective Breeding
-Humans determine which organisms will be allowed to reproduce because of
traits/characteristics that we think are favorable. Example: purebred dogs, cattle farms,
racehorses etc.
Dichotomous Key- (Biological Key)
- Used to classify/ identify organisms based on their physical characteristics.
- AKA an either/ system
- There is always one less choice than the # of organisms you are classifying.
Feb. 13, 2013
Variation
Variation- How does variation occur between species or within species?
Variation occurs and continues because of different traits and characteristics that are
passed on through reproduction. Traits can be delivered into two categories:
1. Heritable Traits- Those traits that air passed on from generation to generation
(parent -> offspring). Example: eye colour, hair, height, skin tone.
2. Non- Heritable Traits- Traits that are usually learned rather than passed on.
Example: Shyness, Piano playing, Athletic ability, hunting ability.
There is a lot of variation within traits. Many traits only have a limited # of choices or
possibilities. These traits have discrete variation. Example: Blood type
Continuous Variation- These are traits that have a wide variety of possibilities.
Example: Height, Weight, hair colour/ shades.
Traits can also be affected by the environment in which an organism lives. Example: Skin
tone, height, weight etc. Resources and the elements can enhance or retard growth.