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Chapter #5 - Notes - Cell Structure and Function
I. 5-1, The Cell Theory
Objectives
*1. List the contributions of vanLeeuwenhoek, Hooke, Schleiden, Schwann, and Virchow to the development of the cell theory.
*2. State the cell theory
*1-A. Scientists leading to information regarding the cell the cell theory.
1. Anton van Leeuwenhoek - invented the microscope in the 1600's. Drew cell seen in drops of H2O
Fig. 5-2, Microscope
2. Robert Hooke, He observed and named cells (cork)
3. In 1833, Robert Brown observed the nucleus.
4. In 1838, Matthias Schleiden stated that all plants are made of cells.
5. In 1839, Theodor Schwann stated that all animals are made of cells
6. In 1855, Rudolf Virchow, he stated all cell come from other cells.
*2-B. Cell Theory
1. All living things are composed of cells.
2. Cells are the basic units of structure and function in living things.
3. All cell come from other cells
Homework - Study Guide, P#43, 44. The Cell Theory
Chapter #5 - Notes - Cell Structure and Function
I. 5-2 - Cell Structure
Objectives:
*1. Name the three structures common to most cells
*2. Discuss the function of the cell membrane, nucleus, and cytoplasm
*3. State the basic difference between eukaryotic and prokaryotic cells
A.*1 Three basic structures of the common cell
1. Cell membrane - The outer covering of the cell.
2. Nucleus - The control center of the cell.
3. Cytoplasm - The material found between the cell membrane and the nucleus.
B.*2 Function and structure of the cell membrane (LD#2547)
1. Regulates what enters and leaves the cell, semipermeable membrane.
2. Aids in protection and support of the cell
3. Separates the cell from the cells surrounding
4. Structure
a. composed of lipids, proteins and carbohydrates
b. Lipids - lipid bilayer, outer and inner covering of the cell membrane.
c. Proteins - Some are located on the surface of the lipid bilayer.
d. Some move around in the lipid bilayer
1. Proteins act as channels, or pores for materials to move through.
2. Proteins can act as pumps to move material into and out of the cell.
e. Carbohydrates - imbedded into the proteins
1. Used for chemical identification, markers for chemicals like hormones that will enter the cell.
2. Allows cells to communicate with each other
3. Allows cells to interact with each other
5. Cell Membranes are not perfect barriers:
a. Poisons can enter the cell
b. Rejection of transplants, if the cell tissues are not closely matched to the donor.
6. Drawing (handout) - Plasma Membrane: Structure (01.033) Color and Label according to Fig. 5-5, page #91.
C. Cell Wall
1. Surrounds plants, algae and some bacteria.
2. Surrounds the cell membrane.
3. Protects and supports the cell
4. Porous to water, Oxygen, CO2, and other substances
5. 2 or more layers (fig. 5-6)
a. 1st layer - layer contains gluey substance, joins to adjacent cells. Made of cellulose, can stretch as cell grows.
b. 2nd layer - In woody plants, secondary cell wall is composed of cellulose and lignin for making the plant stiff (wood).
D. Nucleus - The control center of the cell.
1. Prokaryotes - Cells without a nucleus
a. Some bacteria
b. Lack true organelles with membranes
2. Eukaryotes - Cells with a nucleus
a. Have true organelles with membranes
b. Plants, animals
3. Contains DNA, which have the messages necessary for the making of molecules of the body
4. Parts of the nucleus
a. Nuclear Envelope - Membrane of the nucleus, allows certain materials to enter and leave the nucleus
b. Nucleolus - Made up of RNA, Ribosomes are made of this material.
c. Chromosomes - DNA attached to special proteins, contain the genetic information.
E. Cytoplasm - Material found between the nucleus and the cell membrane.
1. Contains the organelles of the cell
Homework - Study Guide, P#45-46, Cell Structure
I. 5-3, Cytoplasmic Organelles
A. Organelles - Tiny structures that perform a specialized function in the cell. They have a specific job in the cell.
B. Mitochondria - change the chemical energy of food into energy that is useable by the cell.
*Question - Would you expect to find more mitochondria in a skin cell or a muscle cell
*Question - What is the source of the energy produced by the mitochondria?
C. Chloroplasts - Trap the energy from the sun (light energy), and turn it into glucose (chemical energy).
Pigment that absorbs light Chlorophyll
Chlorophyll makes plants green
D. Ribosomes - Organelles where proteins are made.
1. Some attached to ER (rough)
2. Some free floating in cytoplasm
E. Endoplasmic Reticulum - Transports chemicals throughout the cell. A folded membrane that forms a network of interconnected compartments. The ER connects the nuclear membrane with the cell membrane and is involved in the assembly and transport of proteins
1. 2 types
a. Rough ER
b. Smooth ER
F. Golgi Apparatus - Where modification of proteins occur. (ex. digestive juices)
1. 3 Functions
a. collect, packages, distributes molecules from one part of the cell to another.
Question- How many cell structures are related to protein production? 5 - Chromosomes, nucleolus, ribosomes, ER, Golgi Apparatus.
G. Lysosomes - Contain enzymes (produced in ribosomes) and other substances used to digest materials in food vacuoles and recycling waste. It digests excess or worn out cell parts, food, and invading viruses or bacteria (lysosomes digest the cells of a tadpoles tail)
1. Found only in animal cells.
2. Formed by the pinching off of golgi bodies.
H. Vacuoles - Saclike structures that store water, salts, proteins and carbohydrates
1. Water Vacuole - Found in plants, allow plants to grow quickly, also supports plant (turgidity).
2. Food Vacuole Stores and breaks down food
I. Plastids - Ex. Chloroplasts, a form that plastids can take.
1. Functions:
a. store food
b. store pigments
J. Cytoskeleton - Support the cell and drive its movement.
1. Microtubules - Proteins that support the cell, and move organelles throughout the cell.
a. Form centrioles, which are important in animal reproduction (cell division)
K. Cilia - Hairlike structures found surrounding the cell and are supported by microtubules. Cause movement of the cell.
L. Flagella - Long whiplike structures that aid a cell in locomotion. Usually found singly, or in pairs.
Homework - Teacher's Resource Book, Comparing Cells, P#89-90
Study Guide - 5-3, P#47-48
I. 5-4 Movement of Materials Through the Cell membrane
Objectives:
*1. Discuss the process of diffusion
*2. Discuss the process of osmosis
*3. Distinguish between passive and active transport
*4. Describe endocytosis, phagocytosis, pinocytosis
*5. Describe exocytosis
- Passive Transport -movement across a membrane without energy from the cell. From high to low concentration.
*1-A. Diffusion - Process by which molecules of a substance move from areas of higher concentration of that substance to areas of lower concentration. (fig.#5-17)
1. Caused by the constant movement of molecules.
2. Random movement causes movement from a high concentration to one of a low concentration.
3. Equilibrium - condition where the concentration of a material is equal on each side of a membrane. (materials moving into the cell equal the materials moving out of the cell)
4. Selectively Permeable - ability of some substances, but not all, to cross a membrane.
5. Factors of Permeability:
a. Small substances pass through a membrane easier than larger ones.
b. Fat-soluble particles pass through the lipid bilayer easily. (ex. fats and alcohols)
c. Cells differ in what they allow to pass through their membranes.
*2-B. Osmosis - The diffusion of water molecules through a selectively permeable membrane. (Fig.#5-18)
1. Osmotic Balance - Water molecules enter and leave a cell at the same rate.
2. Contractile Vacuoles - Found in unicellular organisms, this organelle pumps water out of a cell, to remove water forced in by osmosis.
C. Facilitated Diffusion - Process in which a carrier protein carries a substance (ex. glucose) across a membrane.
1. Fast, and does not require energy.
2. A form of diffusion.
3. From a high to low concentration.
#3-D. Active Transport - An energy-requiring process (uses ATP) to move a material across a cell membrane against a concentration difference (low to high concentration) (fig.#5-21)
1. example - kidney removing waste from a cell.
2. plant moving minerals across the membrane of root hairs.
#4-E. Endocytosis - Process of taking in large particles of food by infolding of the cell membrane. The cell uses energy to move the materials that are to large to move across by passive or active transport.
1. Phagocytosis - Extensions of cytoplasm surround and engulf large particles of food.
a. Amebas, the cell membrane breaks off and becomes a food vacuole.
2. Pinocytosis - Canals within a cell membrane, fill with water, pinch off and form vacuoles within the cell.
*5-F. Exocytosis - The removal of water or waste from the cell. The vacuole fuses with the cell membrane, and releases materials within the vacuole.
Group Work (2) - Teacher's Resource Book, Passive And Active Transport, P#93, 94.
Homework - Study Guide, 5-4, Movement of Materials Through a Cell, P#49, 50
Project: Movement of Materials through the Cell Membrane
Life Science Mr. Sutherland
Objectives:
To distinguish between passive and active transport.
To describe how materials move through a cell membrane.
Instructions:
Students will choose one of the five methods that show how materials move through a cell membrane.
Students will work by themselves or with a partner on their project.
The project will be presented on a poster board, with a brief written explanation next to each step of the process.
The project will be color-coded; labels that are the same color as the objects being identified (no keys).
Projects will be two-dimensional, in other words, have depth.
Title: Passive or Active transport, and name of process.
Projects will include:
An oral presentation explaining how the materials move through the cell membrane.
Use of 3x5 cards for notes (information in outline form).
Introduction includes opening sentence, what you will be talking about, an introduction of yourself and summary.
Body of presentation includes the steps of the process.
The conclusion will relate back to the introduction, summarize what you explained in your presentation, and finish with a clincher sentence.
Grading:
Neatness 3 points
Title: Active or Passive Transport & name of process 2 points
Creativity of the poster board 3 points
Use of 3x5 cards, with information in outline form 2 points
Color coding 5 points
Two-dimensional project 5 points
Introduction: Opening sentence, description of your presentation, introduction of yourself and summary 4 points
Body of presentation 5 points
Conclusion: Relate back to introduction, summary sentence, and clincher sentence 3 points
I. 5-5, Cell Specialization
Objectives:
*1. Define Cell Specialization
*2. Why is cell specialization important to multicellular organisms.
*1-A. Cell Specialization - Cells are often uniquely suited to perform a particular function within the organism.
1. What are things you, as individuals specialize in?
2. Cells do the same thing in your body.
*2-B. Mucus - water, carbohydrates, and salts that line the air passageways.
1. Cells with Cillia - Line the walls of the air passageways, sweep particles trapped in mucus out of airways.
Homework - Study Guide - 5-5, Cell Specification, P#51,52
II. 5-6, Levels of Organization
Objectives:
*1. Explain the four levels of organization
*1-A. Cells - First Level - Smallest forms of life.
B. Tissues - Second Level - Group of similar cells that perform a similar function.
1. Four types of tissues
a. muscle
b. epithelial
c. nerve
d. connective
C. Organs - Third Level - A group of tissues that work together to perform a specific function.
D. Organ Systems - Fourth Level - A group of organs working together to do a specific job.
1. Examples of organ systems:
a. circulatory system
b. nervous system
c. respiratory system
Homework: Study Guide, 5-6, Levels of Organization, P#52
Homework: Teacher's Resource Book, Vocab Review: Crossword, P#87,88
Ch#5 - Ingestion (Ameba) Name ____________________ Period ___
Mr. Sutherland Microslide Lab
Why does the Ameba appear to be a formless blob? ____________
_____________________________________________________________
Give an example of the prey of an ameba. ____________________
Why would this large species of ameba have as many as 1,000 nuclei?
_____________________________________________________________
Slide #1
What is the magnification of this slide? ___________________
What is a pseudopod? ________________________________________
How many pseudopods can you count? _________________________
Slide #2
When does thigmotaxis occur? ________________________________
What does "C" represent? ____________________________________
What type of food is F1? ___________________________________
What is occurring in this slide? ____________________________
_____________________________________________________________
Slide #3
How is the pseudopod (P1) responding to the changed position of the paramecium?
_____________________________________________________________
What can you now see at F2? ________________________________
What causes the pseudopod P1 to get larger? ________________
_____________________________________________________________
Slide #4
Why are pseudopod P2 and P3 forming? _______________________
_____________________________________________________________
Is it possible that F2 is still alive? Explain. ____________
_____________________________________________________________
What is the magnification of this slide? ___________________
Slide #5
Which pseudopod will probably trap the paramecium F1? Why?
_____________________________________________________________
Why do you suspect F2 is probably dead? ____________________
_____________________________________________________________
Slide #6
Why does to ameba in slide #6 appear to be larger than the ameba in slide #1.
_____________________________________________________________
Slide #7
What has occurred in this slide? ___________________________
_____________________________________________________________
Slide #8
Name the organelle that has formed. ________________________
Where did the membrane surrounding the vacuole come from?
_____________________________________________________________
What will digest the paramecium? ___________________________
What cell in a human body resembles an ameba? ______________