Biology Unit 4 Review

Flashcards*Questions about Food Chains

& Food Webs should come from your Review Packet!!

What is the equation for Photosynthesis?

Sunlight + 6Carbon Dioxide + 6Water Glucose + 6Oxygen

Describe the energy conversion that takes place during Photosynthesis.

Sunlight (Light/Kinetic Energy ) is converted into Chemical Potential

Energy (stored in the bonds of glucose).

Which organisms “do” Photosynthesis?

Autotrophs or Producers

What is the equation for Respiration?

Glucose + 6Oxygen 6Carbon Dioxide + 6Water + ATP

Describe the energy transfer that takes place during Respiration.

Chemical Potential Energy is transferred from the bonds of

Glucose to the phosphate bonds of ATP.

Which organisms do Respiration ONLY?

Heterotrophs…

But remember that autotrophs do Photosynthesis & Respiration

What role do Autotrophs play in the cycling of energy?

Autotrophs take in light-energy and convert it into chemical potential

energy stored in sugars…..

What role do Heterotrophs play in the cycling of energy?

Heterotrophs consume the sugars produced during photosynthesis, and release their stored energy to

make ATP…

How much energy, from a given trophic level, transfers to the

next?

Approximately 10%

How much energy, from a given trophic level, is lost as heat?

Approximately 90%

Which trophic level has the MOST available energy?

The FIRST.

Which trophic level has the LEAST amount of available

energy?

The FOURTH.

Where do you start counting for Trophic Levels?

The producers/autotrophs/plants!

Where do you start counting for Heterotroph / Consumer Levels?

The first Animal!!

What is matter?

Anything with mass and volume.

What is energy?

The ability to do work.

What are the 2 types of energy?

Potential & Kinetic

What does the Law of Thermodynamics state?

• Energy cannot be created or destroyed.

• Energy is converted.• Every time energy is converted,

some is “lost”, thus increasing disorder or entropy in a system.

What is the original energy source for an ecosystem?

Sun

What are the first organisms in any food chain?!

Autotrophs or Producers

Examples:PlantsAlgae

Phytoplankton

What is an autotroph?

An organism which can make its own food by converting

sunlight/chemical energy into sugars.

What is a heterotroph?

An organism which cannot make its own food, and has to eat other

plants/animals.

What does abiotic mean?

Non-living.

What are some abiotic aspects/factors in an ecosystem?

• The amount of sunlight

• The temperature

• The amount of water

• The quality of the water

• The concentration of acid/salt in water

• The types of minerals present

• Soil Type

What does biotic mean?

living

What are some biotic aspects/factors within an

ecosystem?

• Plants

• Numbers & Types of Plants

• Animals

• Numbers & Types of Animals

• Anything living!

What would happen if all autotrophs were removed from

an ecosystem?

All animals would eventually die because they would not have

usable energy!

What would happen if all herbivores were removed from

an ecosystem?

• Plant populations would increase

• Carnivore/Omnivore populations would decrease

What would happen if all carnivores were removed from an

ecosystem?

• Herbivore & Omnivore populations would increase

• Plant populations would decrease

What is an herbivore?

An organism which eats plant material only.

What is a carnivore?

An organism which eats animal material only.

What is an omnivore?

An organism whose diet is balanced with plant and animal

material.

What is a decomposer?

An organism which consumes dead plant and animal matter, releasing

the nutrients back into the ecosystem.

What is most of the energy obtained by organisms used for?

• Life processes

• Respiration

• Moving

• Reproducing

• Maintaining Homeostasis

Why is matter recycled, but energy flows through an

ecosystem?

• Matter = Atoms– Matter is only transformed– Not broken down or “lost” or “unusable”

• Energy – Energy is constantly converted– Energy is always “lost”– Only available energy continues through

(flowing in one direction)

How is carbon stored on earth?

• Carbon Dioxide in the air…

• Carbon in all living things…

• In the ground as fossil fuels…

• In the ocean as dissolved Carbon Dioxide…

Which organisms play a CRUCIAL role in the cycling of

nitrogen?

• Bacteria

• Legumes

• Decomposers

How do bacteria cycle nitrogen?

• Convert Nitrogen Gas into Ammonia

• Convert Ammonia into Nitrates

How do autotrophs cycle carbon?

They take in carbon dioxide from the atmosphere, and release carbon in the

form of glucose….

How do heterotrophs cycle carbon?

They consume carbon-based glucose, and release waste and

carbon dioxide gas into the atmosphere…

What is a food chain?

A single series of feeding relationships in an ecosystem.

What is a food web?

A diagram which shows the complex interaction of all

organisms within an ecosystem.

A Wolf eats a Frog that ate a Fly that ate some Grass…… Which organism

has the MOST energy?

The grass…

A Wolf eats a Frog that ate a Fly that ate some Grass…… Which organism

has the LEAST energy?

The Wolf…

A Wolf eats a Frog that ate a Fly that ate some Grass…… Which

heterotroph has the MOST energy?

The Fly…

A Wolf eats a Frog that ate a Fly that ate some Grass…… What is/are the

autotroph/s?

The grass.

A Wolf eats a Frog that ate a Fly that ate some Grass…… What are the

heterotrophs?

• Fly

• Frog

• Wolf

A Wolf eats a Frog that ate a Fly that ate some Grass…… Which organism

is the herbivore?

The Fly.

A Wolf eats a Frog that ate a Fly that ate some Grass…… List out the

trophic levels.

• Grass = 1st Trophic level

• Fly = 2nd Trophic level

• Frog = 3rd Trophic level

• Wolf = 4th Trophic level

A Wolf eats a Frog that ate a Fly that ate some Grass…… List out the

Consumer Levels.

• Fly = 1st Consumer level

• Frog = 2nd Consumer level

• Wolf = 3rd Consumer level