1. Cell Organelles and Features

2. The Plasma membrane Also called the cell membrane
Selectively permeable
The cell structure that encloses the cell and regulates the passage of materials between the cell and its environment
Allows nutrients into the cell
Allows waste to leave the cell
Also aids in protection and support of the cell.

3. STRUCTURE OF CELL MEMBRANE
Made primarily of phospholipids
Have polar, hydrophilic “water-loving” head
Have a nonpolar, hydrophobic “water-fearing” tail
Water molecule surround the cell membrane
The phospholipids form into a phospholipid bilayer
Cholesterol is found in the membrane to make it more rigid and prevent it from freezing at low temperatures

5. Membrane proteins Cell membranes contain specific proteins
Integral proteins are embedded within the bilayer
Peripheral proteins are on the only one side of the bilayer and are not embedded into it

6. Fluid Mosaic Model
The phospholipid bilayer behaves like a fluid, more than a solid.
The phospholipid bilayer allows other molecules to “float” in the membrane.

7. Cytoplasm Gel-like material that fills the cell
Mainly composed of water, salts and proteins.
In prokaryotic cells all the processes that keep the cell alive happen right in the cytoplasm.
Eukaryotic cells have organelles in which those processes happen.
All of the organelles in eukaryotic cells, such as the nucleus, endoplasmic reticulum, and mitochondria, are located in the cytoplasm.

8. Cytoskeleton
It is a supporting network of long, thin protein fibers that also provide an anchor for organelles.
Certain portions of the cytoskeleton function to help transport materials through different portions of the cell.
Microtubules – hollow structures made up of proteins called tubulins. Play a major role in maintaining the cells shape and cell division.
Microfilaments – thin protein threads composed of actin that play a major role in helping cells move.

9. centrioles Located near the nucleus and made of microtubules.
Function to help organ cell division
Not found in plant cells
Two centrioles make up a centrosome

10. The Nucleus
Most of the functions of a eukaryotic cell are controlled by the nucleus
Contains the chromosomes which are composed of DNA (deoxyribonucleic acid)
Surrounded by a double membrane called the nuclear envelope
Nuclear envelop contains
proteins lined nuclear pores
that are passage ways for
RNA and other materials to
enter/exit the cell

11. Nucleolus Small dense area of the nucleus
Site where DNA is concentrated
Ribosome assembly begins here

12. Mitochondria Found in nearly all eukaryotic cells
The “power house” of the cell
Sites of cellular respiration, a process which supplies the cell with ATP (Adenosine triphosphate)
Bound by a double membrane
The inner membrane had many folds called cristae that carry out cellular respiration
Contains DNA
Inherited from mother

13. Ribosomes
Small, roughly spherical organelles that are responsible for making proteins following coded instructions
Made of RNA and protein
Ribosomes do not have a membrane
Some are found freely floating in the cytoplasm
Others are attached to the rough endoplasmic reticulum

14. Endoplasmic Reticulum (ER)
A complex, internal membrane system that transports substances throughout the cell.
Smooth ER has no attached ribosomes.
Builds lipids like cholesterol
Rough ER has attached ribosomes
Chief function is to make proteins

15. Golgi apparatus Contains sacs that receive materials from the ER.
Modifies, collects, packages, and distributes molecules within the cell or outside the cell.

16. VESICLES
Small, round sacs that are surrounded by a single membrane

17. Organelles That Build Proteins
1. Proteins are assembled on ribosomes.
2. Some proteins complete their assembly on the rough endoplasmic reticulum.
3. Proteins are carried to the Golgi apparatus in vesicles.
Tell students that proteins carry out so many of the essential functions of living things, including the synthesis of other macromolecules such as lipids and carbohydrates, that a big part of the cell is devoted to their production and distribution.
This is a large picture, and will be seen over two slides (there will also be a third slide showing the entire picture).
Help students interpret this picture by asking the following questions.
Encourage students to describe what they see, then fill in the details for them.
Ask: What happens first?
Students will likely notice that a protein is coming off the ribosome.
If students are having a difficult time, help them follow the arrows backwards.
Click to reveal the answer.
Explain that ribosomes are small particles of RNA and protein found throughout the cytoplasm in all cells.
Ribosomes assemble proteins by following coded instructions that come from DNA.
Ask: What happens next?
Students will likely notice that the protein gets fed into the rough ER.
Explain that proteins targeted for export to the cell membrane or to specialized locations within the cell complete
their assembly on ribosomes bound to the rough ER. Introduce the difference between the smooth and rough ER.
Students should notice that the protein ends up in a vesicle.
Explain that newly assembled proteins are carried from the rough endoplasmic reticulum to the Golgi apparatus in vesicles.

18. STEPS IN PROTEIN SYNTHESIS
5. Vesicles are shipped to their final destination.
4. The Golgi apparatus sorts and packages proteins.
Orient students by pointing out that the vesicle is the same one from the previous image.
Ask: What does the vesicle do?
Answer: The vesicle binds to the Golgi apparatus.
Click to reveal the answer.
Explain that the vesicle fuses with the Golgi apparatus. The Golgi apparatus modifies, sorts, and packages proteins and other materials from the endoplasmic reticulum.
Ask: What happens next?
Answer: Vesicles are sent to different places.
Explain that vesicles from the Golgi apparatus are shipped to their final destination within or out of the cell.

19. Making Proteins: Review
Rough endoplasmic reticulum
Nucleus
Ribosome
Cell membrane
Cytoplasm
Protein
Orient students by pointing out that this is the complete process shown in the last two slides. Ask the following questions to assess comprehension.
Ask: Where are proteins assembled?
Answer: ribosomes
Ask: What can you infer about a cell that is packed with more than the typical number of ribosomes?
Answer: When a cell has more than the typical number of ribosomes, you might infer that it produces more proteins than other cells.
Ask: Where is the synthesis of membrane proteins completed?
Answer: in the ER
Ask: How are proteins transported to the Golgi apparatus?
Answer: in vesicles
Ask: What happens to proteins leaving the Golgi apparatus?
Answer: They are sent out of the cell or back into the cytoplasm to be used.
Divide students into groups and have them create flowcharts summarizing the role of each of the following cellular structures in protein synthesis: nucleus, nuclear envelope, ribosomes, endoplasmic reticulum, Golgi apparatus, vesicles, vacuole, and cell membrane. Remind students that proteins can follow multiple processing paths depending on their destination, so the flowcharts may branch at some points.
Smooth endoplasmic reticulum
Vesicle
Golgi apparatus

20. Lysosomes
Contain chemicals called enzymes necessary for digesting certain materials in the cell
Break down old worn out cell parts
Can break down macromolecules
Responsible for breaking down cells when it is time for the cell to die
Play an important role in
maintaining the overall
health of an organisms
by destroying cells that
are no longer functioning
correctly

21. Vacuole “Storage” spaces
A sac to store food, water ,carbohydrates, enzymes, salts and other materials needed by the cell.
Vacuoles in animal cells (if they are present) are much smaller than those in plant cells.

22. Organelles found in plant cells

23. Cell Wall Found in plants, fungi and some bacteria
Cell structure that surrounds the cell membrane for protection and support
Allows for specific substances to pass in and out of the cell.
Made of cellulose

24. Why do plants need cell walls?
Cell walls provide structural support for plants like a Skelton provides structural support for your. Without cell walls, plants would not be able to stand up
What is important about cellulose?
It is a macromolecule that humans cannot digest because they do not have the necessary enzymes; therefore, it passes through your digestive system as “fiber,” cleaning out the intestines.

25. Chloroplast
Contain the green pigment, chlorophyll, which absorbs energy from the Sun to convert carbon dioxide and water into sugar through the process of photosynthesis.

26. movement structures Cilia
Short, numerous projections that look like hairs
Flagella
Longer and less numerous than cilia
400x
Create movement with a whiplike motion
26,367x

27. Fungi Fungi are NOT plants Heterotrophs Eukaryotes Nonmotile
Includes microorganisms such as yeasts, molds, and mushrooms.
Most are saprobes
(live on dead organisms)

28. The Characteristics of Fungi
Absorptive heterotrophs -digest food first & then absorb it into their bodies
Release digestive enzymes to break down organic material or their host
Store food energy as glycogen
Fungi are the principal decomposers in ecological systems. 
BREAD MOLD

29. The Characteristics of Fungi
Important decomposers & recyclers of nutrients in the environment
Most are multicellular, except unicellular yeast
Lack true roots or leaves
MULTICELLULAR MUSHROOM
UNICELLULAR YEAST

30. The Characteristics of Fungi
Cell walls are made of chitin (complex polysaccharide)
Body is called the Thallus
They may have several nuclei within a single cell.
Grow as microscopic tubes or filaments called hyphae

32. The Characteristics of Fungi
Some are edible, while others are poisonous
EDIBLE
POISONOUS

33. The Characteristics of Fungi
Produce both sexual and asexual spores
Classified by their sexual reproductive structures
Spores come in various shapes

34. The Characteristics of Fungi
Grow best in warm, moist environments
Mycology is the study of fungi
Mycologists study fungi
A fungicide is a chemical used to kill fungi
Fungicide kills leaf fungus

35. The Characteristics of Fungi
Fungi include puffballs, yeasts, mushrooms, toadstools, rusts, smuts, ringworm, and molds
The antibiotic penicillin is made by the Penicillium mold
Penicillium mold
Puffball

36. Differences between Plant Cells and Animal Cells
Vacuole small or absent
Large central vacuole
Glycogen as food storage
Starch as food storage
Nucleus at the center
Nucleus near cell wall

37. Similarities between plant cells and animal cells
Both have a cell membrane surrounding the cytoplasm
Both have a nucleus
Both contain mitochondria

38. Differences between plant cells and animal cells
Relatively smaller in size
Relatively larger in size
Irregular shape
Regular shape
No cell wall
Cell wall present