1. Cellular Transport and the Cell Cycle
Chapter 8
Cellular Transport and the Cell Cycle
Section 8.1
Section 8.2
Section 8.3

2. Cellular Transport
Section 8.1

3. Movements across the plasma membrane can be divided into two groups!
Passive Transport
Active Transport

4. Passive - always high to low conc. - does not require energy 1
Passive - always high to low conc. - does not require energy 1. Diffusion (simple) 2. Osmosis 3. Facilitated diffusion
Active - always low to high conc. - NEEDS energy Endocytosis 2. Exocytosis

5. Diffusion- movement of particles from an area of higher concentration (more particles) to an area of lower concentration (less particles) until an equal concentration is met

6. 1. Simple Diffusion Diffusion of particles by using channel proteins
Does not require energy
Movement of small molecules like CO2 and O2
Visit and search for the video titled Cells the Building Blocks of Life and view the segment called Cell Membrane: Diffusion

7. 2. Facilitated diffusion – passive transport of material across the plasma membrane with the aid of transport proteins
Diffusion with the help of carrier proteins
Movement of large molecules like glucose

8. 3. Osmosis – diffusion of water across a selective permeable membrane
What’s going to happen in this picture? (Blue in water and Green in salt)

9. Water is always trying to reach an equal concentration between a cell and its environment

10. Osmosis – diffusion of water across a selective permeable membrane

11. One factor that controls osmosis is a concentration gradient.
Concentration Gradient – an unequal distribution of particles
The greater the concentration gradient, the more likely osmosis will occur

12. Three types of solutions:
Isotonic solution – the concentration of dissolved particles in the solution is the same as the number of dissolved particles in the cell
-“ Iso” – means same, like an isosceles triangle (two sides are the same length)

13. 2. Hypotonic solution – the concentration of dissolved particles in the solution is less than the number of dissolved particles in the cell
- “hypo” means low, as in hypoglycemia (low blood sugar)

14. - “hyper” means high, as in hyperactive (over excited)
3. Hypertonic solution – the concentration of dissolved particles in the solution is more than the number of dissolved particles in the cell
- “hyper” means high, as in hyperactive (over excited)

15. What’s important about osmosis? How does it affect our cells?
Our cells holds 0.9% salt, NO MORE NO LESS
Any solution that is = 0.9% is an isotonic solution to our cells
Any solution that is > 0.9% is a hypertonic solution to our cells
Any solution that is < 0.9% is a hypotonic solution to our cells

16. A simple rule to remember is: SALT SUCKS
Salt is a solute, when it is concentrated inside or outside the cell, it will draw the water in its direction. This is also why you get thirsty after eating something salty.

18. Active - always low to high conc. - NEEDS energy - NOT diffusion 1
Active - always low to high conc. - NEEDS energy - NOT diffusion 1. Endocytosis 2. Exocytosis
Passive - always high to low conc. - does not require energy 1. Diffusion (simple) 2. Osmosis 3. Facilitated diffusion
Visit and search for the video titled Cells the Building Blocks of Life and view the segment called Cell Membrane: Active Transport

19. 1. Endocytosis – process by which a cell surrounds (with vacuole) and takes in large molecules or groups of molecules
ENDO – means “in” to the cell

20. 2. Exocytosis – process in which a cell expulses or secretes materials from cell
Exo – means “exit” or excrete
Used when cells need to expel wastes
Used when cell need to secrete hormones

21. http://www. biologie. uni-hamburg

22. Cell Growth and Reproduction
Section 8.2

23. The Cell Cycle - sequence of growth (interphase) and division (mitosis) of one cell
START HERE

24. MITOSIS
The process in which cells divide and create two daughter cells with the same genetic material as the parent cell

25. Phases of Mitosis:
Prophase
Metaphase
Anaphase
Telophase

26. 1. PROPHASE Longest phase
Sister chromatids appear and are held together by a centromere

27. Centrioles –located outside the nucleus

28. Nucleus starts to disappear
Spindle fibers form
Nucleus starts to disappear

30. Shortest phase
Chromosomes attach to spindle fibers by their centromere and line up in the middle

31. Sister chromatids are pulled apart

33. Spindle begins to break down
New nuclei begin to form

34. CYTOKINESIS End of telophase
The division of cytoplasm to form two new cells Or

35. Tissues Group of cells that begin to work together

36. ORGAN Group of tissues designed to perform a specific function

37. ORGAN SYSTEMS Group of organs that work together

38. Control of the Cell Cycle
Section 8.3

39. I. Normal Control of the Cell Cycle
A. Enzymes Control the Cell Cycle
Necessary to begin and drive the cell cycle, and control the cycle through it’s phases
Uncontrolled dividing comes from failure in the production enzymes
Cancer – one result of uncontrolled cell division

40. Enzymes are directed by genes located on the chromosomes
Gene – segment of DNA that controls the production of a protein
Several enzymes trigger DNA replication

41. II. Cancer: A Mistake in the Cell Cycle
Damaged genes are prompt into action
Tumors – mass of cancer cells
Metastasis – cancer cells can be seen in the circulatory system (spreads the cancer)

42. Tumors can benign or malignant.
Metastasis = Malignant

43. Cancer 2nd Leading cause of death in U.S.A.
Most prevalent – lung, colon, breast and prostate

44. A. Causes of Cancer Genetic
Environmental – cigarette smoke, air and water pollution, UV radiation
Viral infections that damage genes

45. B. Cancer Prevention Healthy Lifestyle Low fat diets
High fiber diets (fruits, vegetables, and grain products)
Vitamins and Minerals (carontenoids, Vit A, C and E)
Daily exercise
Not using Tobacco Products