1. Cells and Cell Systems

2. Cells and Cell Systems
Video: Tour of the Cell

3. Review Cell Theory Two main ideas?
1) All Living things are composed of one or more cells.
2) All cells come from pre-existing cells

4. Review What are the 6 Characteristics of Living Things?
Living things are:
Compose of cells
Reproduce, grow, and repair
Require energy
Respond to the environment
Have a life span
Produce waste

5. A quick review What is this? What are cells?
Cells are the smallest units of life
Most cells are very, very small, so tiny that they can only be seen with the aid of a microscope.
Your body is composed of billions of cells!
Within your body, cells have different functions.
We have blood cells, skin cells, brain cells...the list goes on.
Despite their differences, cells in living organisms for the most part have similar structures and functions.
Scanning electron micrograph of human red blood cells

6. Anatomy of the Animal Cell9 2 1 3 8 5 7 4 6

7. 1) Cell Membrane
Serves as a boundary between the cell and the outside environment
Holds contents of the cell in place
act as a gatekeeper, controlling the movement of materials into and out of the cell
All consist of double layer of fat molecules
The cell membrane is the thin nearly invisible structure that surrounds the cytoplasm of the cell.
In the image at the left you can see that it is a continuous membrane that completely surrounds the cell. It also connects the endoplasmic reticulum, and the nuclear membrane. In the image below we have colored the membrane to highlight its composition. The yellow represents the phospholipids. The purple represents the membrane proteins structure
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8. 2) Cytoplasm
Contains everything between the cell membrane and the nucleus: organelles
consists of primarily of water
Site of chemical activities ie. dissolved gasses and nutrients
Allow transportation between structures
Store waste until depose
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9. 3) Endoplasmic Reticulum (ER)
Spreading throughout the cytoplasm
Protein producing organelles
A series of folded membranes giving it a very large surface area
Provide surface area for cell reactions
Site of lipid (fat) production
Rough ER
Has ribosomes
Spreading throughout the cytoplasm
It is a folded system of membranes that loop back and forth giving it a very large surface area. This membrane provides a surface area for cell reactions. It is also the Site of lipid production.
Smooth ER
Structure where fats (lipids) are made
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10. 4) Ribosomes manufacture proteins for the cell
Location: rER, cytoplasm
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11. 5) Golgi Apparatus Looks like a stack of flattened pancakes
Store protein (produced by rER) and puts them into packages called vesicles
Release to the outside
The golgi body is responsible for packaging proteins for the cell.
Once the proteins are produced by the rough E.R. they pass into the sack like cisternae that are the main part of the golgi body. These proteins are then squeezed off into the little blebs which drift off into the cytoplasm.
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12. 6) Lysosome produced by the golgi body Called suicide sacks
Contain special proteins that used to breakdown large molecules (digestive enzymes)
Patrol and clean cytoplasm
Destroying harmful substances and bacteria that enter the cells
Lysosomes are called suicide sacks. They are produced by the golgi body. They consist of a single membrane surrounding powerful digestive enzymes.
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13. 7) Mitochodria Energy Production (power plant of the cell)
Rod-shaped organelles
Provide energy for cells
Through process: cellular respiration
sugar molecules + oxygen molecules carbon dioxide + water
where cellular respiration takes place (the breakdown of sugars to produce energy for the cell, a process that uses oxygen and produces carbon dioxide and water)
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14. 8) Nucleus Control center containing hereditary material (DNA)
Direct all cell’s activities
Surrounded by a membrane
Cells with a nuclear membrane: Eukaryotic cells
Those without a nuclear membrane: prokaryotic cells
Ex. One-celled organism; bacteria
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15. 9)Chromosomes Found inside the nucleus Contain DNA or genetic material
Holds “construction plan” for all parts of the cell
Duplicated and passed on to other cells

16. How do cells move?
hair like extentions off of the cell membrane

17. Plant Cells
Generally plant cells contain the same features as animal cells such as;
Cell membrane
Cytoplasm
Nucleus
sER and rER
Have some special structures that are not found in animal cells
cell membrane which serves as a boundary between the cell and the outside environment
cytoplasm containing organelles
nucleus containing hereditary material (DNA)
mitochondrion (plural, mitochondria), where cellular respiration takes place (the breakdown of sugars to produce energy for the cell, a process that uses oxygen and produces carbon dioxide and water)
smooth endoplasmic reticulum where lipids are made
rough endoplasmic reticulum where proteins are made with the help of ribosomes

18. What structure do plant cells have different from animal cells?
Vacuole
Cell wall
Chloroplast

19. Cell Wall Outside the cell membrane which provides additional strength
Protects and supports the plant cell
Have small openings (pores) that allow some molecules to pass through:
Gases, water, some minerals
Cell walls are the rigid structure found surrounding plant cells. They provide support for the plant
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20. Vacuole Water and nutrients storage (just as in animal cells)
often with dissolved pigments, waste materials, or other substances
Much larger in plants
Store waste that is produced or absorbed by the plant
Contractile vacoules
These organelles are critical in enabling protozoa to combat the effects of osmosis. Protozoa must constantly excrete the water that enters through their membranes
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21. Chloroplast
Double membrane, made up of stacked discs (thyakoids) and fluid (stroma)
Energy source Food factory of the plant cells
Contain chlorophyll (green chemical molecules)
plant cells trap the energy of light and use it to manufacture food proteins for the cell
Site of Photosynthesis
Animal cells cannot do this
What is chloroplast similar to in an animal cell?
uses light energy to convert six carbon dioxide molecules into one organic six-carbon sugar
Allow plants to make own food, using light from the sun, conbon dioxide and water (site of photosynthesis)

22. Homework: SSA practice
In your textbook Pg. 13 #2-6
On your own, brainstorm about chromosome
Come up with some visual examples that demonstrate what it does.
May help to use action words in its definition as in what it is and what it does to decide what visuals you might use

23. Example: Cytoplasm Function: stores wastes
Visual: a garbage; can store waste
Remember: your visual doesn’t have to look like the that part of the cell, just the function

24. Extras
Centrioles are found only in animal cells. They function in cell division. Notice the 9 sets of 3 arrangement of the protein fibers.
References: The virtual cell page: Personal.tmlp.com

25. Animal Cells Under light microscope Under electron microscope

27. Plant Cells
Under light microscope
Under electron microscope