Cycles of Matter Introduction Matter is made up

Cycles of Matter

Introduction • Matter is made up of tiny particles called atoms. – Hydrogen (H) and oxygen (O) are examples • A combination of two or more of these tiny particles that are joined and act as a unit is called a molecule. – Water H 2 O

The Three Cycles • The important cycles of matter in an ecosystem include – water cycle – carbon and oxygen cycles – nitrogen cycle

The Water Cycle • Water is essential for life • Water continually moves from the Earth’s surface to the atmosphere and back in a process known as the water cycle. • Transpiration- evaporation from leaves of plants.

The Carbon and Oxygen Cycles • Carbon is an element that is found in all living things. • Carbon and Oxygen are cycled through the processes of photosynthesis and respiration • Plants take the carbon dioxide and use it to make glucose during photosynthesis • During respiration, mitochondria use oxygen to break down glucose for energy.

The Nitrogen Cycle • Nitrogen is an element that has to be “fixed” before most organisms are able to use it. • The changing of free nitrogen gas to a useable form is called nitrogen fixation – Most nitrogen fixation is performed by bacteria that live in bumps called nodules on the roots of certain plants. – These plants are known as legumes and include clover, beans, peas, alfalfa, and peanuts. • Nitrogen returns to the environment through animal wastes which are broken down by decomposers.

Roles of Bacteria in the Nitrogen Cycle • Nitrogen-fixing bacteria that live in nodules on the roots of plants change nitrogen gas into nitrogen compounds. • Bacteria that are decomposers recycle nitrogen compounds in the soil • Other bacteria release free nitrogen to the air. What would the role of animals be? – Consume nitrogen when eating plants, or organisms that eat plants – Return nitrogen to the soil through wastes

Cycles of Matter