Warm-Up: Wednesday: November 6th

• When you enter the classroom, pick up a new warm-up sheet from the front chair and a lap top from the cart and login.

Q). What is an ecosystem?

What is an ecosystem?• An ecosystem is all the organisms in a given

area and the nonliving factors that affect them.

Ecosystem Components• Population – A group of organisms that all

belong to the same species that live in a particular area.

• Community – all organisms in a given area

Ecosystem Components• Biotic Factors – All living components in an

ecosystem. (Examples: plants and animals)

• Abiotic Factors – All nonliving components in an ecosystem. (Examples: soil composition, water temperature, amount of sunlight, rocks and minerals present)

Flow of Energy• Energy constantly moves in an ecosystem

from organism to organism. • The flow of energy can be described and

illustrated in food chains, food webs, and pyramids.

Flow of Energy• The SUN is the ultimate source of energy for

all ecosystems across the globe.– Energy entering the ecosystems as sunlight is then

converted by producers (plants) into chemical energy (Sugar/food) through the process of photosynthesis.

– As organisms feed on one another energy is then passed from organism to organism as food.

Flow of Energy• Food provides fuel and building material

to organisms in a process called cellular respiration. –A chemical reaction in which food is

broken down and rearranged to form new substances that support growth.

Food Chains

Trophic Levels• Each level of organisms in the transfer of

energy through an ecosystem is called a trophic level. – Organisms in each trophic level obtain energy and

then…• use some of the energy as fuel to maintain the body• Lose some energy in the form of heat• …and store the rest

*Because organisms in each trophic level use so much energy, they have little energy to pass on to organisms higher up on the food chain.

First Trophic Level• Consists of primary producers or autotrophs

(organisms that make their own energy from the Sun’s energy during the process of photosynthesis)

• Examples include land plants and phytoplankton.

Second Trophic Level• Consists of primary consumers or heterotrophs

(organisms that need to eat other organisms to get energy)– Primary producers are herbivores (organisms that eat

only plants)

Third Trophic Level• Consists of secondary consumers (and

heterotrophs)– Can be omnivores (organisms that eat both plants

and animals) OR carnivores (organisms that only eat animals)

Fourth Trophic Level• Consists of tertiary consumers– Top level consumers and carnivores

Trophic levels Represented

Food Webs• Show many interconnected food chains

describing various paths energy moves in an ecosystem.

BRAIN POP

• Food web/chain video and quiz