Unit 1 Section 3 Cells

Common features: All cells (prokaryotes & Eukaryotes) have several basic features in common.

* Plant cells and animal cells are similar, but do not have exactly the same cell parts and shape.

The structure inside the cell that directs cell activities.
Contains the DNA of a cell.

4. Cell wall

On the outside of some cells, bacteria and plants, this structure functions for support and protection.
There are pores in the cell wall allowing substances to come in contact with the cell membrane.
Types of cell walls:
- Primary cell wall - formed during cell growth, it is composed of parallel layers of cellulose and pectin. This structure allows the cell to expand as it grows. While it does provide support, it is not nearly as strong as the secondary cell wall.
- Secondary cell wall - formed after cell growth stops, it is composed of interwoven cellulose and lignin fibers. This structure is very strong, but does not give. It gives plants their "woody" characteristic.

5. Ribosome

The sites of protein synthesis in a cell.
These small, spherical structures are the most numerous organelles in almost all cells.
Some ribosome's produce protein to be used within the cell and some produce protein that is "exported" to other parts of an organism.

6. Endoplasmic reticulum

A membrane system of folded sacs and tunnels in the cytoplasm.
Rough "ER" is covered with ribosome's. It is common in cells that export proteins and directs the proteins flow.
Smooth "ER" as few or no ribosome's. It functions as a pathway for molecules to follow.

7. Golgi Apparatus

A stack of membranes or sacs that acts to prepare substances for export from the cell.
Once the Golgi apparatus has enclosed the final product in a vesicle, or pouch, the product is sent through the cell membrane.

8. Mitochondria

Large organelles scattered through most cells, they are most numerous in cells that use a lot of energy like liver and muscle cells.
Respiration centers of a cell.

9. Lysosome (animation)

Digestive centers of a cell.
They contain many different types of enzymes and digest things from food particles (macromolecules) to a cell's own worn out parts.

10. Vacuole

Most common in plant cells, they are storage sites within a cell.

11. Chloroplast (Mostly found in plant cells and algae)

Performs photosynthesis - converting light energy into chemical energy.

12. Cytoskeleton

Internal meshwork of protein fibers the provide structural support and involved in various types of cell movement.
Three mains types:
- microfilaments - thinnest type, solid rods composed of actin (globular protein) twisted double chain, support cell shape
- microtubules - thickest type, straight hollow tubes composed of globular proteins called tubulins, disassemble and reassemble, act as tracks for organelles
- intermediate filaments - in between in thickness, made of fibrous protein, rope like structure, reinforce cell shape and anchor certain organelles
Flagella and Cilia - composed of microtubules wrapped in an extension of the plasma membrane
- Provides locomotion in eukaryotic cells

Assignment 1.3a - Cells and the Cell Cycle
Scoring criteria

Part 1

1. Who developed the cell theory and in what year? What is the bases for this theory?

2. What hypothesis or theories suggest where cells originated? Protocells is one idea can you find another? Explain

3. What are the differences between a prokaryotic cell and eukaryotic cell. Include a diagram of each to support your answer.

4. Compare and contrast animal and plant cells, structurally how are they different?

5. Right click on this The living cell and "save target as" to your desk top. Once it has finished downloading view the video and complete the video quiz. Write the video quiz questions and answers with today’s assignment.

Part 2

1. Visit this virtual cell web page Read the "how to use link" Using the virtual cell web page and the “School bus” link to complete this handout: Word doc. format pdf format: (when finished attached to the back of this assignment)

Part 3

You have just been hired as an organelle sales person at Cell-to-Cells Sales Ind. You will be tasked with selling a particular cell organelle. How well do you know the function of cell organelles? Well you are going to need to know your organelles and cells because you are about to become a dealer in the competitive market of cell organelle sales.

Click on this link to get more information on this task.

As a side job to make extra cash you will also be working for Survivor Cells Corporation as a cell organelle buyer and construction manager. You will be be asked to develop a construction proposal to build a specific type of cell for the clients of Survivor Cells Corporation. Your CEO Steve Stemcell has more information on this task a this link .

Honors biology:

1. Build a cell: See link for details (This portion of the assignment will have a separated due date and be completed outside of class)

2. This is a nice site to practice building a cell online.

Section 3-Cells and the Cell Cycle: Part b

Movement of substances in and out of the cell

Some substances, like water, move freely through the cell membrane by a process known as osmosis. In osmosis, particles move easily from an area of high concentration to an area of low concentration by molecular motion only. Cells can push particles in the opposite direction, from low concentration to high, but it will take energy from the cell to do this.

Passive Transport-Passive transport does not require energy.

Types of passive transport:

Diffusion allows particles to travel from an area of greater concentration to an area of lesser concentration until equilibrium is reached.
Facilitated diffusion is when channel proteins control the number of large molecules that diffuse through the cell membrane
Osmosis is the diffusion of water through a selectively permeable membrane from an area of high concentration of water to an area of low concentration of water until equilibrium is reached.
1. See types of solution that can affect cell: Hypertonic, Isotonic, Hypotonic

Active Transport- requires energy.

Types of active transport:

Coupled channels bring sodium and sugar molecules into the cell.
Proton pumps use hydrogen ions to produce ATP molecules.
Sodium-potassium Pumps transport sodium ions out and Potassium Ions into the cell

Other types of Transport

Some cellular organisms ingest food by endocytosis and release waste from a vacuole by exocytosis.
Phagocytosis is when one cell engulfs another cell.
Pinocytosis is when a cell engulfs liquids or dissolved substances.

Practice with Diffusion and Osmosis

See if you can answer these questions using this link:

Explain what is happening in the the animation in the box? You may need to hit refresh on your browser to reactivate the animation.
Watch the animation of water molecules moving across a selectively permeable membrane. Why are the water molecules moving to the right? Hint: Osmosis
Describe the different "Types of Solutions" as explained at this sight.

For more help on Osmosis visit this site and try out the simulations

Cell Membrane

Check out these videos that will help you understand the complex cell membrane

You tube video - Cell membrane

You tube video - Voyage inside the cell membrane

Assignment 1.3b - Cells and the Cell Cycle

Visit the following site and complete 1-6 below (word version ).

1. Read through Membrane Structure concept 1 and the review.

Complete practice 1- list your answers A-H here

2. Read through Osmosis concept 2 and the review.

Complete practice 2- identify the concept being practiced and then write an explanation of how the practice item is modeling that concept (what is happening in the activity and why?).

3. Read through Selective Permeability of Membranes concept 3 and the review.

Complete practice 3 - identify the concept being practiced and then write an explanation of how the practice item is modeling that concept (what is happening in the activity and why?).

4. Read through Passive and Active Transport concept 4 and the review.

Complete practice 4 - list your answers for both the facilitated diffusion practice and active transport practice and then explain why the answers differ between the two.

5. Concept 5 Mechanisms of Active Transport goes above and beyond what is required for this class but you can take a look at it if you would like.

6. Complete the practice quiz at the end and write your answers here (questions 10, 11, 14, & 15 come from concept 5 and can be done to go above and beyond what is required)

The smallest known living thing on Earth is a bacteria in the genus Coxiella. These bacteria are about 8 millionths of an inch (0.2 micrometers) in diameter. Their small size means these bacteria contain only 100 million to 120 million atoms. While this may seem like a large number, keep in mind that the human body has over 5 Billion cells. It is believed that fewer atoms would be unable to build the structures needed to store information and carry out the metabolic processes needed for life.

The largest known animal is the blue whale, Balaenoptera musculus. It is known to reach lengths over 100 feet (30+ meters) and weigh 120 tons. The chart below indicates that all animal cells are about 10 micrometers in diameter. This means that the cells of a blue whale and a human are essentially the same size.

1. Draw a table like this one on your paper or print this word doc. of the table

and use your data and calculations to complete it.

2. Measure and record the diameter of a large marble, a ping-pong ball, and a baseball, in centimeters.

*After completing the table, use your findings to write an explanation and conclusion for the question.

Honors biology: Instead of doing the table above print out this Cell size lab for class. Word doc.

or web page

version. Read the lab carefully and complete the pre-lab portion before we begin the experiment portion.

Red blood cells do not have a nucleus.
They are produced in the "flat" bones of the body, live for about 120 days, and die without reproducing. Their sole purpose is to carry oxygen and carbon dioxide in the blood.

Unit 1 Section 3: Cells and the Cell Cycle