Chapter 1: Interactions of Life Sections 1 & 3 Life Science

Chapter 1: Interactions of Life

Sections 1 & 3

Life Science

Ecology is the study of interactions among living things and their environments.

Ecologists are scientists who study those interactions.

What is a Biosphere? Biosphere- part of the Earth that

supports life.

Biosphere is made up of different Environments that are home to many different kinds of organisms.

What is an Ecosystem??? Ecosystems- consist of all the living

organisms and the non-living things in their environment.

Living Things Biotic Factors – a living thing

in an ecosystem

Abiotic Factor Abiotic Factors – any physical or

chemical part of an ecosystem that living things NEED to survive.– Sunlight– Water– Air– Soil, Sand, Rocks, etc.– Proper Temperature

iPads!!! Create your own Ecosystem using the

LINO APP!

Populations Populations- made up of all the

organisms in an ecosystem that belong to the same species.

Example- Human Population!

Community Community- all the populations in an

ecosystem.

Example- – Arctic Community: fish, seals, polar

bears.

Habitat- the place in which organisms live– Provides: food & shelter, proper

temperature, and Living space theorganism NEEDS to survive.- Example – Pond

Niche – an organism’s role or job in the habitat.

Section 3: Interactions with Communities

What is a Community?

Where does all the Energy come from?

SUN!

What is affected? How?

Energy from the sun is stored in chemical bonds that holds together Atoms.

When these chemical bonds are broken, what must be released?

All organisms need energy in one way or another….

PRODUCERSProducers: organisms that

use a source of energy to make food

Example: Plants use sun for Photosynthesis

What if organisms can’t receive sunlight?

Chemosynthesis – is when bacteria produces food using heated chemicals released from underwater vents.

CONSUMERS Consumers: Organisms that cannot

make their own food AKA - Heterotrophs

1. Herbivores- “vegetarians” plant eaters

Ex- Rabbits, Deer, Cows

2. Carnivores- animal eaters Ex- Lions, Coyotes

3. Omnivores- eats plants & animals Ex- Humans, Bears

4. Decomposers- consume waste & dead organisms

Ex- Earthworms, Mushrooms, Mold, Fungi

- help recycle once-living matter

Scavenger – an organism that feeds off of once-living organisms– Ex – turkey vulture

What are some things that organisms depend on other organisms for?

FOOD CHAIN Food Chain- a model to show the

feeding relationships between a single producer and a chain of consumers

FOOD WEB Food Web – model of the feeding

relationships between many overlapping food chains

ENERGY PYRAMID -shows the amount of Energy

available at each feeding level.

STOP HERE

What are some “cycles” in nature?

Section 2 Cycles – Picture Notes (see Binder)

BIOMES – Section 4 See Biome Project in Binder

Chapter 2: Interactions Within

Ecosystems

Life Science

Habitats & Niches

Habitat- the place in which organisms live– Provides: food & water, shelter, proper

temperature, and Living space theorganism NEEDS to survive.- Example – Pond

Niche – an organism’s role or job in the habitat.

Niches What is a Niche?

Niches- how an organism survives, how it obtains food and shelter, how it finds a mate and cares for its young, how it avoids danger.– Special adaptations that improve survival

are often part of an organism’s niche.

Patterns Exist in Populations

Patterns in SPACE - how animals or plants place themselves, depends on how they meet their needs to survive.– Space is needed for food or water.

Examples – School of fish, herd of elephants

Patterns in Populations Patterns in TIME

– Population sizes change depending on climate.

– Examples – Cicadas emerge every 17 years, bears hibernate, birds migrate, jelly fish in August!

Population sizes can also

depend on predators.

SECTION 2.2

Symbiotic Relationships

Symbiotic Relationship – means a close relationship between two species

MUTUALISM

1. Mutualism- where both species benefit

Example: Bee and Flower

Explain…

COMMENSALISM

2. Commensalism- where one organism benefits and the other is not affectedExample: Clown Fish and Anemones

Explain…

PARASITISM

3. Parasitism- where one organism benefits, and the other is harmed

Example- Dogs and Ticks

PREDATOR/PREY Predator- consumers that capture

and eat other consumers

– Predators can limit the size of populations

– Predators can also increase & decrease the number of different organisms in an ecosystem.

PREDATOR/PREY Prey- organism that is captured by a

consumer (or predator)

Competition Competition- two or more organisms

that seek the same resource at the same time.

Effects of Competition Competition for food, living space, or

other resources can LIMIT the population.– Prevents Pop. Growth

Competition is most intense among individuals of the same species.

Measuring Pop. Methods

1. Count the # of species

2. Trap-Mark-Release

3. Sample Count (used to estimate the sizes of larger populations)

Population Size Pop. Size- indicates whether

population is healthy and growing.

Population Density- the size of a population that occupies a specific area

Limiting Factor- anything that restricts the # of individuals in a population.– Can be living or nonliving– Can affect other populations

Carrying Capacity- the largest # of individuals of one species that an ecosystem can support.

What if the Carrying Capacity exceeds?

Not enough resources, death occurs, species are forced to move.

What Affects Pop. Size? List some things that can affect

Population Sizes…

Exponential Growth Exponential Growth- the LARGER a

population becomes, the FASTER it grows.

Changing in Pop. Populations can change in size when

new members enter or exit the pop.

BIRTH RATE- # of births in a given time

DEATH RATE- # of deaths in a given time