Cell Processes Notes

A. Movement of Materials in & out of Cells

1) MOLECULE: Two or more atoms chemically bonded together. FOR EXAMPLE: O + O O2 H + H + O H2O 6C + 12H + 6O C6H12O6

2) CONCENTRATION: The degree to which molecules are packed together. LOW HIGH

3) DIFFUSION: The movement of molecules from an area where their concentration is high to an area where their concentration is low.

Diffusion of food coloring in water. Don’t copy this slide just watch. High concentration Low concentration Equal concentration

Diffusion of food coloring in water. High concentration Equal concentration Low concentration

4) SELECTIVELY PERMEABLE MEMBRANE: A membrane that permits only certain particles to pass through. (FOR EXAMPLE: The cell membrane allows water and oxygen to pass through freely).

Equal Concentration inside & outside Low Concentration High Concentration Don’t copy this slide just watch.

Equal Concentration inside & outside Low Concentration High Concentration

5) OSMOSIS: The diffusion of water in and out of the cell. Low Concentration High Concentration Copy the definition for Osmosis only. Equal Concentration Inside & Outside

6) In “Osmosis,” water molecules from a higher concentration to a lower concentration of H2O molecules. move

7) Adding “Salt” or other particles to water lowers the concentration of H20 molecules. High Concentration Low Concentration

Don’t copy this slide just watch. Is the concentration of water molecules higher inside or outside of the cell?

Low concentration of H2O Don’t copy this slide just watch. Low concentration of H2O High concentration of H2O Is the concentration of water molecules higher inside or outside of the cell?

Low concentration of H2O Don’t copy this slide just watch. Low concentration of H2O High concentration of H2O Now we have equal concentration inside and outside the cell

8) ACTIVE TRANSPORT: The process in which a cell 8) ACTIVE TRANSPORT: The process in which a cell (from ATP) to transport particles into or out of the cell. uses energy

EXAMPLE: An Amoeba engulfing another organism.

9) ENDOCYTOSIS: movement of a large particle into the cell using the cell membrane to surround the particle and form a vesicle.

10) EXOCYTOSIS: movement of a large particle out of the cell by first surrounding it with a vesicle and then moving it to the cell membrane where it is expelled.

B. How Cells Get Energy

C. The Cell Cycle

Vocabulary 1) Cell Cycle: The life cycle of a cell which begins when the cell is formed and ends when it divides and forms two new cells. 2) Chromosome: Is a coiled bundle of DNA and protein that is located in the cell nucleus. 3) Centromere: The region that holds chromosomes together when a chromosome is duplicated. Also the region of spindle attachment when individual chromosomes are pulled to opposite ends of the cell.

CELL CYCLE STICK FIGURE DRAWINGS

INTERPHASE 1st DNA DNA is copied so there are twice as many strands of DNA.

MITOSIS - (Prophase) spindle Chromosomes spindle Nuclear membrane breaks up, spindle begins to form, and DNA coils up to form Chromosomes.

MITOSIS - (Metaphase) Centromere spindle 3rd Sister Chromosomes Centromere Sister Chromosomes spindle Spindle attaches to centromere and chromosomes line up in middle of cell.

MITOSIS - (Anaphase) Centromere 4th Centromere Sister Chromosomes Sister chromosomes are pulled to opposite ends of cell by spindles.

MITOSIS - (Telophase) 5th Chromosomes begin to uncoil back to strands of DNA. Two new nuclear membranes begin to form.

CYTOKINESIS 6th Cytoplasm pinches in and all the organelles are equally divided between the two new daughter cells.