Chapter 1: Nature of Science Section 2: Living Things
Chapter 1 Section 2: Living ThingsA. Organism: Any living thing 1. Organisms vary in size. (microscopic to very large) 2. Behaviors vary from one organism to the next. 3. Needs differ from one organism to the next.
B. Living Things Are Organized 1. Organisms must show some level of organization; here are the levels. a. Cell: Basic unit of life working together to do a certain job. b. Tissue: Cells working together to do a certain job. i. Example: heart tissue, brain tissue c. Organs: A group of tissues working together. i. Example: Heart, Kidney, Brain, Skin d. System: Group of organs working together. i. Example: 10 human body systems e. Organism: Group or organ systems working together.
C. Human Body Systems: 1. Respiratory: Helps breathing; Lungs, nose, etc 2. Skeletal: Support; femur, skull, ribs, etc. 3. Integumentary: Protection; Skin, fingernails, hair. 4. Digestive: break down food and get rid of solid waste; Stomach, Large intestine, mouth 5. Muscular: Controls movement; biceps, triceps, etc. 6. Excretory: Get rid of liquid waste; kidney, bladder. 7. Reproductive: Reproduce; testes, ovaries. 8. Nervous: controls feeling; brain, spinal chord, nerves.
D. Living Things Respond 1. Living things respond to a stimulus. a. Stimulus: anything that causes some change in the organism. b. Response: the reaction to the stimulus 2. Internal and External Stimulus a. External: Dog running to kitchen when hearing food bag being opened. b. Internal: Cells regulate amount of water, temperature, and energy being used. 3. Homeostasis is the regulation of an organism’s INSIDE despite outside changes. a. Example: sweating when you have a fever even if the room you are in is cold.
E. Living Things Adapt 1. Adaptation is a characteristic an organism has which makes it better able to survive in its surroundings.F. Living Things Must Use Energy 1. Energy gives the organism the ability to do work. a. Most energy comes from the sun; directly or indirectly. b. Do we get our energy from the Sun?
G. Living Things Grow and Develop 1. Growth: Increase in size and mass 2. Development: change from an infant to an adult; changing into a more complex organism. 3. All living things have a Life Span. a. The length of time an organism is expected to live. b. Life span is made up of: Birth, Development, and Death.
H. Living Things Reproduce 1. Reproduction: The ability to make similar offspring to the parents. 2. Without reproduction, living things would not exist to replace those that die. a. Without reproductions species would become extinct.
I. What do living things Need? 1. Living Things need a place to live. a. Living things are limited in where they live by the environment. b. When the environment they live in becomes too crowded the competition for space costs lives; organisms then relocate. c. Example: Desert, Bottom of the ocean, hot/cold. 2. Living Things Need Raw Materials a. Every organism needs water, oxygen, and food. b. Most organisms are 50% water. c. Humans are 70 % water.