Characteristics of Living Objects

6 Characteristics of Living Objects 1. Living things have cells Cell - The smallest unit of life - Has a membrane - Contains all components needed for life Organism - A form of life - Made of 1 to trillions of cells

2. Sense and Respond to Change Stimulus - Causes a reaction or change Ex: Heat Homeostasis - Maintenance of a stable internal environment - Requires a reaction from external environment Ex: Sweating and shivering Internal - On the inside External - On the outside

3. They can reproduce - Involves two parents Sexual Reproduction - Offspring shares characteristics from both parents - Involves a single parent Asexual Reproduction - Offspring is identical to the parent Offspring - The product or child from reproduction

4. Contains DNA DNA Deoxyribonucleic Acid - A molecule - A copy of DNA is passed to the organism’s offspring. - Controls structure and function of a cell Heredity - Passing of traits

5. Use Energy Life activities require energy Metabolism - Total of all chemical activities that occur in an organism. 6. Grow and Develop - Grow during some period in their lifetime - May develop and change over time

The Necessities of Life

The Necessities of Life 1. Water - Cells contain ~ 70% water - Most chemical reactions require water (Metabolism) 2. Air - A mixture of gases including oxygen and carbon dioxide - Needed to release energy from food

3. A Place to Live - Contains everything needed to live - Creates competition between organisms 4. Food - Provides energy - We break down food to get the nutrients Producers Make their own food

Consumers Eat other organisms for food Decomposers Feed off dead organisms or their waste

Molecule - A very small particle made of atoms - Nutrients are made out of molecules - The 5 major molecules found in living things are Proteins, Carbohydrates, Lipids, ATP, and Nucleic Acids Element - A small atom that can exist on its own - The 4 major elements found in living things are Carbon, Oxygen, Hydrogen, and Nitrogen

The 5 Major Molecules 1. Proteins -Large molecules made of amino acids -Organisms break down proteins from food to make proteins for their body -Have many different functions in the cell. Enzyme - A protein that speeds up a chemical rxn

- Molecules made from sugars to store energy 2. Carbohydrates - Molecules made from sugars to store energy Simple Carbohydrate - Made from one or few sugar molecules - Made from hundreds of sugar molecules Complex Carbohydrate Plants store this in the form of starch. Potato = stored starch

3. Lipids - Compounds that can’t mix with water Phospholipids - Form the cell membrane Lipids also come in the form of fats and oils - When organisms use their stored carbs, they then use fats and oils for energy

4. ATP Adenosine Triphosphate - Major energy source for cells - Energy from carbs and lipids have to be converted to ATP to be able to be used. - Large molecules 5. Nucleic Acids - Subunits called nucleotides - Contain all info required to make proteins - DNA is a nucleic acid