1. Cell Organelles and their Function

2. Cell Membrane Cytoplasm More on the cell membrane to come…
Semi-permeable
Regulates movement in & out
Cytoplasm
All the material from the nucleus to the cell membrane
More on the cell membrane to come…

3. Nucleus Nucleolus Chromosomes Nuclear Envelope
Control center of the cell
Nucleolus
Located inside the nucleus
Ribosomes are made here
Chromosomes
DNA material seen in the nucleus
Made up of Chromatin (DNA and proteins)
Nuclear Envelope
Encloses the nucleus
See next slide for chromatin

4. Chromatin DNA wrapped around proteins
A protein
Chromatin condenses to form the chromosomes

5. Endoplasmic Reticulum
Synthesizes and transports proteins (Rough ER)
Synthesizes lipids and steroids (Smooth ER)
Golgi Apparatus
Collects, modifies, sorts, and secretes cell products
Vesicle
Picks up molecules from golgi apparatus and transports in cell or to other cells
manufactures membranes and secretory proteins . In certain leukocytes (white blood cells), the rough ER produces antibodies . In pancreatic cells, the rough ER produces insulin.

6. Ribosomes Synthesize proteins during translation Free – in cytoplasm
Bound – on rough ER

7. Lysosome Peroxisome Break down cellular waste products and debris
Rid cells of hydrogen peroxide and other toxins

8. Mitochondria
Creates energy through cellular respiration

9. Centrosome In animal cells only Play a role in cell division
Help to organize cytoskeleton
Animal cells have Centrioles which are paired structures within the centrosome
Located near the nucleus

10. Vacuoles Central Vacuole (in plant cells only) Food vacuoles
Contractile vacuoles
Holds food, water and minerals
Formed when particles are taken into the cell
Pump water out of cells

11. In Plant Cells Only Chloroplast (example of plastid) Cell Wall
Plastids – A double membrane bound organelle involved in the synthesis and storage of food, and is commonly found within the cells of photosynthetic organisms, like plants.
Chloroplast
(example of plastid)
Site of photosynthesis in plants only
Cell Wall
Thick outer covering outside the cell membrane
Protects and supports a plant cell

12. Cytoskeleton
A network of protein filaments that organizes structures and activities in the cell.
All help to maintain the cell shape and other specific functions
See next slides

13. Components of the Cytoskeleton
Microtubules
Hollow tubes made of proteins known as tubulins
Main Functions
Cell motility (cilia and flagella)
Chromosome movements in cell division
Organelle movements

14. Components of the Cytoskeleton
Microfilaments
Two intertwined strands of actin (a protein)
Main Functions
Changes in cell shape
Cytoplasmic streaming
Cell motility (pseudopodia)
Cell division (cleavage furrow formation)

15. Components of the Cytoskeleton
Intermediate Filaments
Fibrous proteins supercoiled into thicker cables
Main Functions
Anchorage of nucleus and other organelles
Formation of nuclear lamina

17. The Endomembrane System
A cell's endomembrane system consists of the rough and smooth endoplasmic reticulum, Golgi apparatus, vesicles and plasma membrane, all working together to transport cellular materials.

19. Cell Membrane
Allows materials to move in and out of the cell.

20. Made of a phospholipid bilayer
The “fluid-mosaic model” Of an Animal Cell
Made of a phospholipid bilayer
Two layers of lipids (they can move. They need to be fluid to work properly). Allow certain materials to pass through
dotted with proteins
Proteins aide in certain molecules moving through the membrane
Gen bio. Lipids and proteins only. Copy of this slide

21. Phospholipid bilayer of Cell Membrane
Water loving
Water fearing
The arrangement of the phospholipid bilayer allows only certain molecules to pass through the cell membrane.
“head region” – likes water
“tail region” - does not like water
Some large molecules, like sugar
Cannot “fit” through this layer
Small molecules generally move through easily
Also if the molecule is soluble in the “tail” region it will go through faster.

22. Cell Membrane of an Animal Cell
ECM – extracellular matrix (cells attach to this and send signals to one another. Made of protein fibers)
Carbohydrate chains –assist in cell signaling
Proteins-aid certain molecules moving through the membrane
Cholesterol- keeps membrane fluid, from not freezing or becoming too liquid
Phospholipid bilayer –allow certain materials to pass through
Regeneration of cells – regrowing finger

23. How do substances move in and out of cells?

24. How Do Substances Move In and Out of Cells?
Diffusion – movement of molecules from greater concentration to lesser concentration.
No Energy Required by the cell
Passive Transport

25. DIFFUSION – A type of Passive Transport

26. How do substances move in and out of cells?
2. Osmosis – movement of water across a membrane from greater to lesser concentration.
Examples – water into plant cell, salt on slugs, preserving meats
Also passive transport (no energy needed)

27. Review of terms Solute – what is being dissolved
Solvent – What is doing the dissolving
Solution – solute + solvent

28. Types of Solutions Hypertonic - higher concentration of solute
Hypotonic - lower concentration of solute
Isotonic - equal concentration of solute

29. Less solute / More water More solute/less water
Hand out

30. Hand out answer

31. In a solution with lower concentration of solute (more water)
In a solution with equal concentration of solute and solvent
In a solution with higher concentration of solute

32. Osmosis and animal cells

33. “Special Cell Processes” -Examples
Salt on slug
E.coli
Osmosis on lettuce
Egg osmosis

34. Facilitated Diffusion Passive Transport No Energy required
-Molecules move from Higher concentration to Lower concentration.
-Molecules are being “helped” through by proteins
The molecules “glide” through, like a boat going through a channel

35. Active Transport -Requires Energy
Molecules are now moving the opposite way we have discussed.
Molecules move from a lower concentration to a higher concentration.
Uses a transport protein
Energy comes from
ATP
Lower concentration
Review of diffusion and osmosis
Higher concentration

36. Active Transport-example
The Sodium (Na), Potassium (K) pump
High Na
Low K
High K
Low Na
Yahoo search sodium potassium pump - animation

37. Bulk Transport across the cell membrane require energy
Endocytosis
Taking materials into the cell

38. Bulk Transport across the cell membrane require energy
Exocytosis
Secreting materials
(moving materials from inside the cell to outside the cell)
Usually moving products