Closed 10/26

Totaled 9/21 Mr F

What is life? I don't know!

Definitions:

Homeostasis: Regulation of the internal environment to maintain a constant state; for example, sweating to reduce body temperature, and shivering to create friction, and therefore heat.

Organization: Being composed of one or more cells, which are the basic units of life. This is the thing that viruses and fires lack, and therefore, they aren't considered organisms.

Metabolism-The consumption of energy to maintain homeostasis. This includes shivering when you are cold in order to heat up the body, and sweating while your body is getting hot in order to cool down.

Growth- Maintenance of a higher state of synthesis than catabolism. A growing organism increases in size in all of its parts rather than simply accumulating matter.

Adaption-The ability to change over a period of time in response to the environment. A short term example of this is developing calluses on your hands. This keeps certain species alive, so they can overcome hindrances to survival. Those that fail to adapt will die out and become extinct.

Response to stimuli- A response can take many forms, from the contraction of a unicellular organism when touched to complex reactions involving all the senses of higher animals. A response can often be expressed by motion.

Reproduction- The ability to produce new organisms, whether asexually(reproduced by a single organism) or sexually (produced by two organisms).

 here's the characteristics of life in more detail.

Why aren't viruses considered alive?

Viruses aren't considered to be living because of one crucial point -  they are not made out of cells. In 1935 scientists established that viruses are made merely of RNA or DNA surrounded by a protien shell. The lack the internal structure to be alive. Even though they demonstrate most of the charactersitics of life, if a being does not have ALL the characteristics of life, they are not alive.

According to dictionary.com there are many definitions of what "life" is

The first definition and probably most accurate states life as the condition that distinguishes organisms from inorganic objects and dead organisms, being manifested by growth through metabolism, reproduction and the power of adaption to environment through changes originating internally. 

Now all the characteristics in this definition have come from the notes we took in class today!

So any living thing has to have all these characteristics to be considered "life"

     BEST VIDEO OF THE CHARACTERISTICA OF LIFE.  EVEN HAS AWSOME MUSIC.

I think that this video presents everything perfectly.  The video lists all of the characteristics of life, explains them, and shows them throught the video.  One thing that i dont understand completely are cells.  When i think of living things, I think they can sense things, they can think, they have a purpose in life for themselves, not only to have a purpose in life.  Cells on the other hand, I dont think that they can think, sense things, or do things for themselves.  All that they do is divide, so that there are more of them (ex. someone growing).  Can they think that they can reproduce, or is it just something that they do?  Are they there just to make other things live, or do they have a purpose on their own?  Either way, cells are important, and if you don't have them, you are not living.

     http://library.thinkquest.org/5420/cellwhat.html

This is a link to a website that I thought made understanding what cells are and what they do pretty easy. It's kind of aimed more at younger kids, but I think it's easier to understand without confusing terms. There are also a few simple diagrams and clear labels for each of the parts of a cell.

http://health.howstuffworks.com/adam-200092.htm

---> I chose this video because Mr. Forstbauer briefly talked about homeostasis in class today and I think that we will be learning about the process more in-depth. This video shows how homeostasis occurs in the human body and uses examples that are referred to in our everyday lives. For instance, the demonstration consists of how blood sugar is maintained and how negative feedback works. The level goes beyond normal range, and then back. However, homeostasis does not just occur in human cells. The creators explain how the endocrine system controls the state of balance in the body and releases hormones.

10/26 What is this doing here? Kellie - be careful wher you put stuff 

Chapter 2 Sections 1-3 Notes

2.1: The Nature of Matter

1. Atoms
   1. atom- the basic unit of matter
   2. the subatomic particles that make up atoms are protons, neutrons, and electrons
   3. nucleus- the center of the atom that contains the protons and neutrons
   4. electron- negatively charged particle with 1/1840 the mass of a proton
2. Elements and Isotopes
   1. element- a pure substance that consists entirely of one type of atom
   2. isotopes- atoms of the same element that differ in the number of neutrons they contain
   3. because they have the same number of electrons, all isotopes of an element have the same chemical properties.
   4. compound- a substance formed by the chemical combination of two or more elements in definite proportions

3. Chemical Bonds

   1. the main types of chemical bonds are ionic bonds and covalent bonds
   2. ionic bond- formed when one or more electrons are transferred from one atom to another
   3. ions- positively and negatively charged atoms
   4. covalent bond- forms when electrons are shared between atoms
   5. molecule- the smallest unit of most compounds
   6. van der Waals forces- a slight attraction that develops between the oppositely charged regions of nearby molecules

2.2: Properties of Water

1. The Water Molecule
   1. A water molecule is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms.
   2. cohesion- an attraction between molecules of the same substance
   3. adhesion- an attraction between molecules of different substances
2. Solutions and Suspensions
   1. mixture- a material composed of two or more elements or compounds that are physically mixed together but not chemically combined
   2. solution- mixture of two or more substances in which the molecules of the substances are evenly distributed
   3. solute- the substance that is dissolved
   4. solvent- the substance in which the solute dissolves
   5. suspensions- mixtures of water and nondissolved material
3. Acids, Bases, and pH
   1. pH scale- measurement system designed to indicate the concentration of H+ ions in solution
   2. acid- an compound that forms H+ ions in solution
   3. Acidic solutions contain higher concentrations of H+ ions than pure water and have pH values below 7
   4. base- a compound that produces hydroxide ions in solution
   5. Basic, or alkaline, solutions contain lower concentrations of H+ ions than pure water and have pH values above 7
   6. buffers- weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH

2.3: Carbon Compounds

1. Macromolecules
   1. monomers- small unit that can join together with other small units to form polymers
   2. polymer- large compound formed from combinations of many monomers
   3. Four groups of organic compounds found in living things are carbohydrates, lipids, nucleic acids, and proteins.
2. Carbohydrates
   1. carbohydrates- compounds made up of carbon, hydrogen, and oxygen atoms
   2. Living things use carbohydrates as their main source of energy. Plants and some animals also use carbohydrates for structural purposes
   3. monosaccharides- single sugar molecules
   4. polysaccharides- large macromolecules formed from monosaccharides
3. Lipids
   1. lipids- made mostly from carbon and hydrogen atoms
   2. common categories: fats, oils, and waxes
   3. Lipids can be used to store energy. Some lipids are important parts of biological membranes and waterproof coverings
4. Nucleic Acids
   1. nucleic acids- macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus
   2. nucleotides- consist of three parts: a 5-carbon sugar, phosphate group, and a nitrogenous base
   3. Nucleic acids store and transmit hereditary, or genetic, information
   4. ribonucleic acid (RNA)- contains the sugar ribose
   5. deoxyribonucleic acid (DNA)- contains the sugar deoxyribose
5. Proteins
   1. proteins-macromolecules that contain nitrogen as well as carbon, hydrogen, and oxygen
   2. amino acids- compounds with an amino group on one end and a carboxyl group on the other end
   3. Some proteins control the rate of reactions and regulate cell processes. Some are used to form bones and muscles. Others transport substances into or out of cells or help to fight disease

Chapter 2 Section 4 "Chemical Reactions and Enzymes" Notes

1. Chemical Reactions
   1. chemical reaction- a process that changes one set of chemicals into another set of chemicals
   2. reactants- the elements or compounds that enter into a chemical reaction
   3. products- the elements or compounds produced by a chemical reaction
   4. Chemical reactions always involve the breaking of bonds in reactants and the formation of new bonds in products
   5. CO2+H2O--->H2CO3 (reaction can be reversed) H2CO3--->CO2+H2O
2. Energy in Reactions
   1. Chemical reactions that release energy often occur spontaneously. Chemical reactions that absorb energy will not occur without a source of energy.
   2. 2H2+O2--->2H2O
   3. activation energy- the energy that is needed to get a reaction started
3. Enzymes
   1. catalyst- a substance that speeds up the rate of a chemical reaction
   2. enzymes- proteins that act as biological catalysts
   3. Cells use enzymes to speed up chemical reactions that take place in cells
4. Enzyme Action
   1. substrates- the reactants of enzyme-catalyzed reactions