What is Life? Levels and Branches of Biology Biology 1
Dec 30, 2015
Biology is the study of what?Break down the word –
“ology” = study of“bio” = life (comes from the greek word bios)
Biology is the science that wants to understand the LIVING world
Biologists use the SCIENTIFIC METHOD to study living things
What is Life?
Living things share several characteristics – what are they?
Group Project:Work together to come up with the
characteristics that all living organisms share.Write down what you come up with in your
notebooks (EVERYONE!!!!)You have 10 minutes.
What is life?
Living things are made up of units called Cells
Living things reproduceLiving things are based on a universal genetic
codeLiving things grow and developLiving things obtain and use materials and
energyLiving things respond to their environmentLiving things maintain a stable internal
environmentTaken as a group, living things change over
time.
What is life?
What are Cells?Small self-contained unitsGrow, reproduce and respond to their
surroundingsUnicellular means: One Celled (“Uni” = One)
MicroorganismsMulticellular means: Many Celled (“Multi” =
Many)Animals and plantsDiversityHuman body: 85+ different types of cells
Living Things – Made up of Cells
Sexual ReproductionMajority of multicellular organismsTwo cells from different parents combine to
make the new organismAsexual Reproduction
Majority of unicellular organismsOne cell divides in half to form two new
organisms
Living Things - Reporoduce
What is Genetic Code?How do dogs produce dogs, flies produce flies?DNA
Deoxyribonucleic Acid
Living Things – Based on Genetic Code
Life CyclesTypical Growth and Death Patterns
Differentiation (Development)Changes – Eggs -> Maggots -> Flies
Living Things – Grow and Develop
Metabolism – Builds up or breaks down materials to live.
How does Algae do this?How do Plants do this?How do Sheep do this?How do Wolves do this?How do Buzzards do this?
Living Things – Need Materials & Energy
Homeostasis – process in which an organism keeps their
internal conditions relatively stable.
What happens when you get sick?
How does a bird maintain its body temperature in the snow and in the heat?
Living Things– Maintain Internal Balance
Ecology - What is it?The study of living things and how they interact with nonliving things.
Each organism depends in some way on other living or nonliving things.
Levels of organizationBiosphere: Broadest level of organization
including all things found on Earth and in it’s atmosphere.
Ecosystems: Includes all the organisms and the nonliving environment found in a particular place.
Community: Only includes living parts of the ecosystem.
Levels of organizationPopulation: Includes all the members of a
species that live in one place at one time.
Organism: Simplest level of organization that consist of only one living thing.
Example: BiosphereThink of it this way: If the earth were an apple the biosphere would be only as thick as the skin on the apple.
Are Living Things distributed evenly throughout the biosphere?
No!!!!
Example: EcosystemA pond is an ecosystem that contains a variety of living things: fish, turtles, aquatic plants, algae, insects, and bacteria.
Also don’t forget the nonliving: chemical and physical composition (water, sunlight)
They all interact in ways that affect their survival.
Example: Community
All the living organisms in the pond: fish, turtles, plants, algae, and bacteria.
Can contain thousands of species
*Group Names*
Example: PopulationAll the members of a species that live together at one time. Like a species of frogs living in the same pond and interacting.
Biotic and Abiotic FactorsBiotic: all the living things in environment:
animals, plants, bacteria, etc.
Abiotic: all of the non-living things in environment: pH, salinity, temp, minerals, amount of sunlight, and precipitation.
Biotic and Abiotic interactionsAbiotic and Biotic factors are NOT
independent.
Ex: Plants (biotic) need nitrogen (abiotic)
The NicheA species’ niche is its way of life, or role the
species plays in its environment.
A species niche includes a range of things: Methods of how it obtains foodNumber of offspringTime of reproductionAll other interactions with its environment
Niche DifferencesA species niche can change in a single
generation.Some species survive better than others.
Specialist: have narrow nichesEx. Koala who feeds
only on a few species of eucalyptus leaves.
Generalist: tolerate a broad range of thingsEx. Virginia Opossum
lives all over the U.S. and eats almost anything
Species InteractionsSeveral types:
1. Predation – predator captures, kills, and consumes preyImportant role in natural selection
http://www.youtube.com/watch?v=sWkOjowSFzs&feature=endscreen
http://www.youtube.com/watch?v=vdg9gkmWsEA&feature=related
Predator/Prey Videos
Avoiding predators - contb. Advertising poison –
caterpillars eat poisonous plant – bird eats them and then gets sick or dies.
Avoiding predators - contc. Mimicry – harmless
species resembles a dangerous or distasteful one.
Harmless viceroy (bottom) looks like poisonous monarch butterfly.
2. Parasitism – one individual, the parasite, feeds on another individual, the host
Can you think of some different types of Parasites?
Species Interactions
4. Competition – results from the use of same resources by 2 or more species.
Can you think of some animals that compete for food, water, land?
Species Interactions
5. Mutualism – cooperative relationship between 2 organisms in which both benefit.Ex.
Acacia tree and ant (protection and
water)
Next slide: Sea anemone and
clown fish (protection and food);
6. Commensalism – interaction in which one species benefits, the other is not helped or harmedEx. Cattle and egrets
A. Primary succession – development of community in an area not previously inhabited.Ex. New island (bare rock), sand dune, lava flow
B. Secondary Succession – replacement of species after a disruption (by fire, storm, human activity)
Pioneer species – the first to appear in succession;
small and fast growingEx – lichen
Climax Community – Stable, mature ecosystem. Stays the same a long time.
Ex – Forest, prairie