Characteristics of Life How many can you remember? – Made of cells – Movement – Require nutrients, oxygen, water – Respond to environment – Can reproduce – Grow/Develop over time

Staying Alive Living things must be able to interact with their environments in order to keep themselves alive.

Living things must take in NUTRIENTS Animal cells (by themselves or part of a larger organism) must take in nutrients (glucose—C 6 H 12 O 6 ) Mitochondria inside the cell are responsible for breaking glucose apart to release energy.

CELLULAR RESPIRATION In order to do this, they require the molecule OXYGEN. This is why all living things must also take in oxygen—to be able to break down their food molecules (glucose). This process is called CELLULAR RESPIRATION. We represent the process with this equation:

CELLULAR RESPIRATION by Brainpop CELLULAR RESPIRATION by Brainpop 1.How do we get the glucose we need to perform cellular respiration? 2.What do your cells produce as a result of doing cellular respiration? 3.How does your body get rid of the waste produced by cellular respiration?

PHOTOSYNTHESIS Plant cells create their own sugars through the process of PHOTOSYNTHESIS. This occurs in the CHLOROPLAST organelle. We represent the process with this equation:

PHOTOSYNTHESIS Plants then perform cellular respiration in order to break down the sugar into energy Photosynthesis by Brainpop 1.What are the “ingredients” for photosynthesis? 2.What is the pigment in chloroplasts that traps sunlight called? 3.Another name for glucose is ______________

Photosynthesis and Respiration What do you notice about these two processes? THEY ARE EXACT OPPOSITES

Organisms Maintain Homeostasis HOMEOSTASIS HOMEOSTASIS = the ability of a living organism to regulate its internal environment so as to maintain a stable, constant condition. Clip—How Stuff Works

Homeostasis Examples – TEMPERATURE: we are warm-blooded creatures and must maintain a temperature of about 37 degrees C even when temperatures outside are warmer or cooler (This is called thermoregulation) – FLUID BALANCE: Your body maintains the right amount of water in your body

Homeostasis Examples – BLOOD COMPOSITION: Your body maintains the right amount of sugars, fats, acidity (pH), pressure, etc. If your blood sugar is too high or too low you have diabetes. – Not allowing the accumulation of WASTES – Maintaining the right oxygen & carbon dioxide levels in the body

HOMEOSTASIS The major organs that help regulate homeostasis in the body are: THE BRAIN, KIDNEY, LIVER, and your EXCRETORY organs, and your ENDOCRINE SYSTEM Really, they ALL work together to keep you alive!

HOMEOSTASIS by Brainpop HOMEOSTASIS by Brainpop 1.Give an example of an organism that maintains constant body temperature. Give an example of an organism that does NOT maintain constant body temperature. 2.What kind of FEEDBACK (positive or negative) slows down or stops a process in a living organism? 3.How do your excretory organs help maintain homeostasis?

METABOLISM – All the chemical reactions going on in a living system (or body) to keep the organism alive.

METABOLISM

Metabolism by Brainpop Metabolism by Brainpop 1.What is the difference between CATABOLIC and ANABOLIC reactions? 2.What would happen if our bodies could not metabolize glucose? 3.How do plants interact with other parts of the food chain? 4.If your body were a car, glucose would be the:

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