All organisms require ________ to make amino acids.

The biggest mammal that inhabits the ocean.

A plants response to light.

Scientific study of interactions among organisms and between orgainsims and their physical enviorment.

Each step in a food chain or food web.

Water continuously moves between the oceans, atmosphere and land.

A specific scientific name identifies a _______ of an organism.

Transports solutions of nutrients and carbohydrates produced by photosynethesis.

First step in asking a question to solve a problem.

Relative amount of energy or matter contained within each trophic level in a given food chain or food web.

Bacteria obtain energy by converting nitrates into nitrogen gas, which is released into the atmosphere.

A cold-blooded vertebrate that spends some time on land but must breed and develop into an adult in water.

Plants that are able to produce seeds

The living part of the enviorment.

Chemical energy used o produce carbohydrates.

Elements pass from one organism to another and among parts of the biosphere through closed loops.

An animal with four pairs of legs and a body with two segments.

The pattern of growth, occuring at the end of plants.

Consists of all life on Earth and all parts of the Earth in which life exsits.

Digest decomposers that live on and in detritus particles.

Forms a part of vital molecule such as DNA and RNA.

An air-breathing cold-blooded egg-laying vertebrate with an outer covering of scales or plates and a bony skeleton.

Outer covering of stems.

An assemblage of different populations that live together in a defined area.

Total amount of living tissue within a given trophic level.