| A | B |
|---|
| element | any type of substance that can't be broken into a simpler substance |
| each element makes up | one kind of atom (the smallest unit of an element) |
| compounds | when two or more elements combine chemically |
| molecule | the smallest unit of a compound |
| inorganic compounds | don't contain carbon |
| organic compounds | contain carbon which is found in most living things |
| the most important organic compounds found in living things are | 1. proteins; 2. carbohydrates; 3. lipids; 4. nucleic acides |
| proteins | made up of different combinations of amino acids |
| there are only 20 amino acids | but they can be rearranged in thousands of ways to form different proteins |
| proteins make up part of the | cell membranes |
| protiens make up organells | and build body structures such as muscles |
| food that are high in proteins are | meat, eggs, fish, nuts and beans |
| enzymes | are a type of protein that speeds up chemical reactions |
| lipids | contian more energy than carbs |
| lipids are important | for proteins of cells, they help make up the cell membrane |
| examples of lipids are | fats, oils and waxes |
| nucleic acids | contain instructions cells need to carry out all funtions of life |
| 2 kinds of nucleic acids are | DNA and RNA |
| DNA | carries information about an organism that is passed from parent to offspring and it directs all cell functions. |
| DNA is found in the | chromatin in the nucleus |
| RNA | plays an important role in production |
| RNA is found in | cytoplasm and in the nucleus |
| without water | chemical reactions could not take place |
| water helps cells | keep their size and shape |
| water helps the temperature | of cells from changing to rapidly |
| cell membrane | is selectively permeable and allows some substances to pass through while others can't |
| the cell membrane is usually | permeable to substance like O2, H2O, CO2 but usually not to larger molecules |
| substance move in and out of cells in 3 ways | 1. diffusion; 2. osmosis; 3. active transport |
| diffusion (passive transport) | the process by which molecules move from an area of higher concentration to an area of lower concentration |
| osmosis | the diffusion of water molecules (passive transport) |
| water molecules move by diffusion from an area where | they are highly concentrated through the membrane to an an area where they are less concetrated |
| active transort is the | movement of materials through a cell using energy |
| engulfing | is when the cell membrane engulfs a particle, pinches off and forms a vacuole to dispose of which uses energy |
| transport proteins | pick up molecules and carry them in and out using energy |
| every living thing needs | energy |
| photosynthesis is the process | by which a cell captures energy from the sun light and uses it to make food |
| photosynthese two stage process | 1. capture the sun's energy, this occurs in leaves and other green parts of the plant; 2. roots absorb water from the soil. |
| chloroplasts, mostly in leaves, | give plants the green color |
| pigments | are colored chemicals that absorb the light (green, orange, yellow) |
| roots absorb water from the soil and CO2 | enter through the stomata |
| The stomata is | small openings under the leaf |
| H20 and CO2 go to the chloroplasts | where they go through chemical reactions producing glucose |
| plants use some sugar | for food |
| oxygen is released | through the stomata |
| photosynthesis is essential | for the air that we breathe |
| 21% of the earth's atmosphere | is oxygen |
| almost all of that oxygen is produced by | photosynthesis |
| nearly all living things obtain energy directly or indirectly from the | energy of the sunlight |
