Discovering Cells Cell-Basic unit of structure and function of living things. Microscope-Allowed discovery of cells. First microscope was a simple lens and future microscopes turned into compound microscope consisting of two lenses. Magnification-The ability to make things look larger than they are.

Microscope (cont.) The lens in a microscope magnifies an object by bending the light that passes through them. Convex Lens- A lens with a curve shape. Resolution-The sharpness of an image.

Cell theory All living things are composed of cells. Cells are the basic unit of structure and function in living things. All cells are produced from other cells.

Inside cells Organelles- Tiny structures with in the cell that perform certain functions. Cell Wall- Only in plant cells, gives plants their rigid structure, determines what objects come in and out of the cell. Made up of cellulose. Cell membrane-Protects the cell and controls what substances come in and out of a cell. Nucleus-Control center of the cell. Directs all the functions of the cell.

Nuclear Membrane-Protects the nucleus and allows things to pass in and out. Chromatin- Floating in the nucleus, directs the functions of the cells, carries the genetic material that controls the cell division. Nucleolus-Produces ribosomes. Cytoplasm- Clear gel like fluid that contains the organelles. Mitochondria- Produces the energy to carry out the cell functions. Endoplasmic Reticulum-Passageways that carry proteins and other material throughout the cell.

a Ribosomes- Factories to produces proteins. Golgi Bodies-Receive proteins and other materials from the endoplasmic reticulum and sends them to other parts of the cell. Chloroplasts-Capture energy from sunlight and uses it to produce food for the cell. Vacuole-Storage areas that hold waste, water, and food. Lysosomes-Small round structures that contain chemicals that break down food.

Bacterial Cells No nucleus Contains ribosomes Much smaller than most normal cells. Can cause diseases.

Chemical Compounds in Cells Element-A substance that cannot be broken down into simpler substances. Atom-Smallest unit of an element. Compound-Two or more elements chemically combined. Molecule-The smallest unit of a compound.

Organic and inorganic compounds Organic compounds are those compounds that contain carbon. These are usually associated with living things. Inorganic compounds do not contain carbon. Most important group of organic compounds are carbohydrates, lipids, proteins, and nucleic acid.

Carbohydrates Energy rich organic compound made of carbon, hydrogen, and oxygen. Sugars and starches are carbs. Foods include potatoes noodles, rice, and bread.

Proteins Large organic molecules made of carbon, hydrogen, oxygen, nitrogen, and in some cases sulfur. Foods include meat, eggs, fish, nuts, and beans. Proteins consist of smaller molecules of amino acids. There are 20 types of amino acids that combine to form different structures. Enzyme is a protein that speeds up a chemical reaction in a living thing.

Lipids Energy rich organic compounds made of carbon, hydrogen, and oxygen. Usually in the form of fats, oils, and waxes. Cholesterol is a lipid that plays an important function in cell walls. When there is too much it can cause heart disease.

Nucleic Acids Large organic molecules made of carbon, oxygen, hydrogen, and phosphorus. Contain the instructions that cells need to carry out the functions of life. Two kinds- DNA, and RNA. DNA- The genetic material that carries information about an organism that is passed from parent to off spring. RNA- Plays an important role in the production of proteins. Without water most chemical reactions within cells could not take place.

Cell’s Environment. Selectively Permeable- Some substances can pass through the cell membrane, some cannot. Three methods by which substances move into and out of a cell. Diffusion, osmosis, and active transport.

Diffusion. The process by which molecules tend to move from an area of higher concentration to an area of lower concentration. Caused by molecules that are bouncing off of each other.

Osmosis. The diffusion of water molecules through a selectively permeable membrane. Move from an area of higher concentration to an area of lower concentration.

Active Transport The movement of materials through a cell membrane using energy! Passive Transport uses no energy and includes osmosis and diffusion. Transport Proteins- proteins that are used to carry materials in the process of active transport.(Kluesner says your dopey, not me)

Engulfing. The act of a cell wall surrounding what it is taking in and creating a vacuole. Cell Size- Cells are small because they need to move a lot of material to stay alive. They would not function if they were too large. And we lived happily