1. Cellular Transport
Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration.
The diffusion of water across a selectively permeable membrane is called osmosis.
The structure most responsible for maintaining cell homeostasis is the plasma membrane.
If a cell is placed in salt water, water leaves the cell by osmosis.

2. Hypotonic
In a hypotonic solution, the concentration of dissolved substances is lower in the solution outside the cell than the concentration inside the cell.
Water enters(moves) into a cell placed in a hypotonic solution.

3. Hypertonic
In a hypertonic solution, the concentration of dissolved substances outside the cell is higher than the concentration inside the cell.
Water moves out of a cell if the cell is placed in a hypertonic solution.
If cells are placed in a strong sugar solution, water will pass from the cells to the sugar solution.
If it is not watered, a tulip plant wilts because it loses turgor pressure.
Plasmolysis—loss of water from a cell resulting in a drop of turgor pressure.

5. Passive Transport 3 Types
Facilitated diffusion
Diffusion
Osmosis
Compare and contrast the structure and function of channel proteins and carrier proteins.

6. Active Transport
A cell can move particles from a region of lesser(lower) concentration to a region of greater(higher) concentration.
Dynamic equilibrium-continuous movement of particles but no overall change in concentration.
Endocytosis
Exocytosis

7. Cell Growth and Reproduction
Figure 8.9 KNOW
As a cell’s size increases, its volume increases much faster than its surface area.
Dark-stained structures that carry the genetic material are the chromosomes.
The cell cycle is the sequence of growth and division of a cell. G1
S stage G2
Mitosis
The majority of a cell’s life is spent in the growth period in known as interphase.
G1, S Stage, and G2 are all Interphase

8. Mitosis
A cell enters its period of nuclear division called mitosis.
Interphase
Prophase
The two halves of the doubled structure are called sister chromatids
Sister chromatids are held together by a structure called a centromere.
By the end of prophase
The chromosomes have coiled tighter
The nuclear envelope has broken down
The nucleolus has disappeared
Centrioles present—only in animals not plants
The spindle is a football-shaped, cagelike structure consisting of thin fibers made of microtubules.
Metaphase

9. Mitosis cont. Anaphase Telophase Cytokinesis Fig 8.15 KNOW
The centromeres split and the sister chromatids are pulled apart to opposite poles of the cell.
Telophase
Cytokinesis
Fig 8.15 KNOW

10. Control of the Cell Cycle
A series of enzymes monitors a cell’s progress from phase to phase during the cell cycle.
Cancer-uncontrolled cell division
A gene is a segment of DNA that controls the production of a protein.
When people move from one country to another, cancer rates appear to follow the pattern of the country in which they are currently living, not their county of origin.
Causes of cancer:
Environmental Influences
UV Radiation
Viruses