Victor Gr. 7 - Science - What is Life?

• 1. cellular organization
• 2. contain similar chemicals
• 3. use energy
• 4. grow and develop
• 5. respond to their surroundings
• 6. reproduce

A cell is the basic unit of structure and function in an organism.

Unicellular, or single-cell organisms, include bacteria... the most numerous organisms on earth.

Multicellular means... composed of many cells.

• 1. water
• 2. carbohydrates (cell's energy source)
• 3. proteins
• 4. lipids (building materials of cells)
• 5. nucleic (the genetic material) - the chemical instructions that direct the cell's activities.

Living things use energy to grow and develop.

Growth - is the process of becoming larger.

Development - is the process of change that occurs during an organism's life to produce a more complex organism.

A stimulus is a change in an organism's surroundings that causes the organism to react.

A response is an action or change in behavior.

To reproduce means to produce offspring that are similar to the parents.

Spontaneous generation is the mistaken idea that living things arise from non-living sources.

In a controlled experiment, a scientist carries out two test that are identical in every way except for one factor.  

The one factor that the scientist changes is called the variable.  The scientist can conclude that any differences in the results of the two tests must be due to the variable.

• 1. energy
• 2. water
• 3. living space
• 4. stable internal conditions

• 1. the sun's energy
• 2. carbon dioxide
• 3. water
• *These three things combine in the organism to make their own food.

An autotroph is an organism that makes its own food.

A heterotroph is an organism that cannot make their own food.

Organisms need water to do such things as obtain chemicals from their surroundings, break down food, grow, move substances within their bodies, and reproduce.

All organisms need a place to live, a place to get food and water, and find shelter.

Because there is a limited amount of living space on Earth.

• 1. living space
• 2. water
• 3. minerals

Homeostasis is the maintenance of stable internal conditions despite changes in the surroundings.

Ex: Your body's regulation of temperature.