The Building Blocks of Life Chapter 1: Cells The Building Blocks of Life

What is Life? Ideas?

Which of the following are living things? Dog Moss Car Mildew Water

Living Things –have 6 characteristics Have a cellular organization Contain similar chemicals Use energy Grow and develop Respond to their surroundings Reproduce

1. Cellular Organization All organisms are made up of cells. Cells are the basic unit of structure and function in an organisms. Unicellular Organisms - organisms made up of one cell Ex: Bacteria (These are the most numerous organisms on earth.) Multicellular Organisms - organisms made up of many cells. There are many different types of cells and each type has its own functions. Ex: Brain cell, nerve cell

2. Contain Similar Chemicals Water-most common Carbohydrates-energy source Proteins-building blocks of cells (hair, muscles, fingernails) Lipids-building blocks of cells Both carbohydrates and lipids are made up of O, H and C. Nucleic acids-genetic material, instructions

3. Use Energy To grow and repair You use energy to breath, digest, think, move, heal

4. Grow and Develop Development-Process of change that occurs during an organisms life to become more complex. Brainstorm: How do lving things grow and develop?

Response to Surroundings Stimulus -a change in surrounding that causes an organism to react Example: changes in temperature, light, sound, etc. Response -the organism’s response or action to the stimulus or change Example: A tree bends towards sunlight

Reproduction Reproduction- produce offspring similar to parents

Living Things need 4 Things Energy Water Living Space Stable Internal Conditions

1. Energy Food! Plants are autotrophs. Autotrophs are self- feeders. They make their own food out of energy from the sun and CO2 Heterotrophs (“other feeders”) eat autotrophs or other heterotrophs to receive energy from the sun in an indirect way.

2. Water Water is needed to obtain chemicals from surroundings, break down food, grow, and move substances in body. (92% of blood is water.)

3. Living Space Living things must share and compete for living space.

4. Stable Internal Conditions The surroundings of living things change, but they must keep stable internal conditions. Homeostasis-the maintanance of stable internal despite changes in surroundings Ex: Body temperature Ex: Barnacle-wet vs. dry

Read pg 22-23 together

Big Idea Questions What are the six characteristics of all living things? What four things do all living things need? Describe a controlled experiment.

Vocabulary Organism Cell Unicellular Multicellular Development Stimulus Response Reproduce Spontaneous generation Controlled experiment Manipulated variable Autotroph Heterotroph homeostasis