The cell

1. All living things are composed of one or more cells.

2. Cells are organisms’ basic units of structure and function.

3. Cells come from only existing cells.

Because the surface is increasing slower than the volume, so at one point the surface can’t keep up anymore.

Eukaryotes have a nuecleolus, membrane-bound organelles. They are found in animales, plants, alge, fungi and protozora.

• Separates the inside of the cell from the outside environment

• Flexible

• Let’s substances in and out (for energy and waste movement)

• Called “semi permeable” or “selectively permeable”

• Made up of two layers of phospholipids

• Gel/liquid type substance inside the cell

• Contains water,salts, and organic molecules (containing carbon)

• Organelles are found within the cytoplasm

• Most common organelle in a cell

• Produces proteins

• Free-floating ribosomes produce proteins for the cell

• RER ribosomes produce proteins to be used elsewhere in the organism

• Smooth ER (no ribosomes) and rough ER (have ribosomes attached)

• Made up of a folded up membrane structure

• Helps move molecules throughout the cell by creating transport

• Can store proteins for future use

• Works with the ER to transport molecules and looks similar to the ER

• Final processing and packaging area

• Sends molecules out of the cell via vessicles

• Made up of two membranes. Outer membrane separates organelles from cytoplasm.  Inner membrane is called cristae and is folded up to increase surface area.  Why?  Faster, more points energie production

• Have their own DNA and can grow, divide, and fuse with each other.

• Creates ATP which is the useable form of energy for cells.

• Can be many mitochondria in the same cell.  Why? In certain places have more glucose to produce ATP

• It is believed that mitochondria used to be their own DNA_cells, but evolved to work together with eukaryotic cells and became one.

• Vesicles that contain digestive enzymes

• Enzymes can be used to break down food, kill foreign (ex. bad bacteria), and recycle worn-out parts of the cell.

• Interestingly enough, lysosomes form fingers in embryo development!

• Act as a supportive skeleton for the cell

• Are broken down and rebuilt at times to give support when/where needed

• Specialized microtubules help pull apart chromosomes during cell division

• Used for movement purposes - either of the organism or of foreign debris.

• Cilia are small and are found in large numbers

• Flagella are long and found by themselves or in pairs

• Examples: Sperm have flagella.  Human respiratory tract has cilia.

• “Brain” of the cell. Build DNA/RNA that codes for everything in the organism.

• Has a double membrane around it with pores for movement in and out.

• Inside the membrane is the nucleoplasm which contains DNA and protein.

• Dark spot is called the nucleolus and produces new ribosomes.

• Strong structure which surrounds the cell membrane

• Made of cellulose, which is a carbohydrate that we cannot digest (fiber!)

  • What does fiber do for us? It helps to clean up the digestive tract

• Has pores throughout it to allow for movement into and out of the cell

• LARGE storage sacs in plants

• Store waste materials and enzymes

• Pushes all other organelles up against the cell membrane/wall

• Gives extra strength to the cell due to the high pressure pushing against the wall

• Different functions and different types

• Chloroplasts are green and turn solar energy into chemical energy (food)

• Chromoplasts can be yellow to red and also create chemical energy

• Leucoplasts store food that has been produced for plants