BIOLOGY_CELLS

=I. BASICS OF CELLS=

I-A. GENERAL CHARACTERISTICS OF CELLS

 * Cells are the basic units of structure and function in living things.
 * New cells are produced from existing cells
 * Size: Could range from 5-50 micrometers in diameters
 * Cells contain DNA: the biological information it carries
 * They all contain a Cell Membrane
 * Two categories of cells: **Eukaryotes** & **Prokaryotes** depending if they have a nucleus. (Nucleus is a large membrane-enclosed structure that contains genetic material in the form of DNA and controls many of the cell's activity.)

I-B. EUKARYOTES
>
 * Eukaryotes are cells that contain DNA in nuclei
 * Eukaryotes are generally larger than Prokaryote cells
 * Eukaryotes are more complex than Prokaryote cells.
 * They contain dozens of structures and internal membranes, many are specialized for performing task
 * In Eukaryotic cells, the structure is divided into 2 major portions: The Nucleous & the Cytoplasm

I-C. PROKARYOTES

 * Cells that do not enlcose DNA in nuclei
 * Prokaryotes cells are particularly smaller and simpler than Eukaryotes cells
 * They perform everyday task that are associated with licing things. (**Grow, reproduce, respond to enviroment, and glide along surface and swim through liquids.**)
 * The organism we call bateria are prokaryotes.



=II. CELL STRUCTURE=

**II-A. GENERAL CHARACTERISTICS OF CELL STRUCTURE**

 * Each cell functions like small city
 * Cells are made up of multiple complex structures, each with a different role in the cell's operation.o
 * In Eukaryotic cells, the structure is divided into 2 major portions: The Nucleous & the Cytoplasm
 * **Cytoplasm** - the portion of the cell outside the nucleus
 * Each major component of plant & animal eukaryotic cells act as specialized organs AKA **organelles** (meaning little organ)
 * Using the city comparison, the following charts shows the functions of the major organelles in Eukaryotic cells:

II-B. GENERAL SUMMARY OF CELL STRUCTURE ORGANELLES


(1) NUCLEUS, (2) NUCLEOLUS. (3) RIBOSOMES, (4) VESICLES, (5) ROUGH ENDOPLASMIC RETICULUM, (6) GOLGI APPARATUS, (7) ([|electron micrograph]) ([|karyotype])** || Controls heredity ([|Transcription-] 1 or [|Transcription-2] DNA makes RNA)** || Composed of **DNA and proteins** Chromatin- a collection of chromosomes || and [|nuclear pore complex]** || Encloses the nucleoplasm and separates nucleus from rest of the cell || Double membrane Made of lipids and proteins Contains pores || ([|diagram showing DNA])** || Produces energy (ATP) for the cell by cellular respiration Inner folded membranes are called **cristae** Area surrounded by cristae is called the **matrix** || [|(Ribosomes on ER)]** || Protein synthesis **[|(Translation]****)** || Composed of rRNA Free ribosomes- those suspended in cytosol Bound ribosomes- those attached to ER || 1. important in the synthesis of lipids, 2. metabolism of carbohydrates, 3. detoxification of drugs and poisons; Rough ER- assists in the production of secretory proteins, most of which are glycoproteins (proteins attached to carbohydrates) || Membranous system of interconnected tubules and flattened sacs which are continuous with the nuclear envelope; Smooth ER- no ribosomes are present Rough ER- ribosomes are attached || Usually 1 large vacuole in plant cells, whereas there are many small vacuoles in animal cells-- called vesicles. Contractile vacuoles pump out excess water || Work best at pH 5 || A. Structure 1. **[|Carrier Proteins]** B. Transport 1. **[|Diffusion]** 2. **[|Osmosis]** [|Plasmolysis in red onion- video] 3. **[|Active Transport]**- Na+/K+ Pump 4. **[|Phagocytosis]** 2. Gives animal cells their shape || Composed of 2 phospholipid layers and proteins || eukaryotic cells || Composed of microtubules Found only in animal cells || 2. Moves fluids over surface of tissues || Composed of microtubules || Chlorophyll is located within thylakoids
 * ** Name of Organelle ** || ** Major Function ** || ** Other information ** ||
 * **Nucleus (2) ** || Controls all cell activities ||  ||
 * **[|Nucleolus] (1) ** || Synthesizes rRNA and ** assembles ribosomes ** ||  ||
 * **[|Chromosomes]
 * [|(DNA replication]****- DNA makes DNA)
 * **[|Nuclear Envelope]
 * **[|Mitochondria]
 * [|(Mitochondrial electron transport)]** || Double membrane structure
 * **[|Ribosomes] (3)
 * **[|Endoplasmic Reticulum (ER)] (5) ** || Smooth ER-
 * **[|Vacuole] (10) ** || Stores and excretes substances, especially water || Membrane bound sac
 * **[|Golgi Apparatus] (6)** || Processes and packages substances for export from the cell and to other parts of the cell || Flattened membranous sacs ||
 * **[|Lysosomes] (12)** || Digests (hydrolyzes) substances || Membrane-bound sacs that contain digestive enzymes
 * **[|Cell Membrane]** || 1. Regulates what enters and leaves a cell
 * **[|Cell Wall]l** || Gives support and protection to plant cells || Composed of cellulose and lignin in
 * **[|Centrioles]** || Important in cell division || Located in pairs
 * **[|Cilia and flagella]** || 1. Cell movement
 * **[|Chloroplast]** || Photosynthesis
 * [|(Photosynthesis electron transport)]** || Double membrane structure
 * Grana** are stacks of thylakoids;
 * Stroma**- fluid outside of thylakoids ||
 * **[|Cytoskeleton] (7)** || Structural support and cell movement || Composed of [|microtubules], intermediate filaments, and [|microfilaments] ||

II-B1. CELL MEMBRANE aka Plasma Membrane (city wall & gates)

 * **Functions **: regulates what enters and leaves the cell (also called selective permeability). It also gives the cell shape and protection (refers to animal cells)
 * **Structure **:
 *  Made of 2 layers of proteins and fat molecules called lipids.
 * The structure is interlocking which helps bind the 2 layers together.
 * The proteins contained in the membrane are **selective permeable** which means it picks and choose which chemicals are allowed to pass
 * Lipid Soluable substances like alcohol can pass through cell membrane by dissolving the membrane itself.
 * Lipid Insoluble substances cannot pass but water is able to pass through the membrane by way of passing through the protein lined pores. See diagram of cellular membrane below
 * For **plant cells**, it's referred to as **__CELL WALL__** :
 * 1) **Function** -
 * acts as the skin or shell for the cell membrane
 * allows plant cells to withstand high internal pressure without bursting
 * works with Vacuoles to create the skeletal support of the cell
 * 1)  **Structure** - the natural secretion of the cell membrane and made mostly of cellulose
 * the cellulose (provides the rigidity) cemented together with lignin
 * cellulose fibrois are deposited in alternating layers to provide strength
 * contains pits that makes it permeable

II-B2. VACUOLE (Towers that support the city walls)

 * ** Function: **
 * Its main function however is ** to increase cell size ** & ** surface ** area of cells so that the absorption of ions is enhanced.
 * In plants it can act as a storage area for ions, metabolic products such as sugars and amino acids, and toxic compounds
 * produces turgor pressure against cell walls as a means of wall support
 * stores water and various chemicals
 * may also store insoluble wastes.
 * [[image:http://upload.wikimedia.org/wikipedia/en/thumb/8/8e/Plant_cell_structure_svg_vacuole.svg/649px-Plant_cell_structure_svg_vacuole.svg.png width="379" height="276" caption="Vacuole of Plant cell"]][[image:http://upload.wikimedia.org/wikipedia/en/thumb/e/e0/Biological_cell_vacuole.svg/400px-Biological_cell_vacuole.svg.png caption="Vacuole of Animal Cell"]]
 * ** Structure: **
 * A single layer of unit membrane enclosing fluid in a sac
 * Fluid pressure builds up in the vacuole causing the cell to become elongated and extended increasing surface area and cell size
 * How Vauole Increase Cell Size

**II-B3. CYTOSKELETON (7)**

 * Cellular "[|scaffolding]" or "[|skeleton]" contained within the [|cytoplasm].
 * The cytoskeleton is present in all cells
 * It is a dynamic structure that maintains cell shape, protects the cell, enables cellular motion (using structures such as [|flagella], [|cilia] and [|lamellipodia]), and plays important roles in both intracellular transport (the movement of [|vesicles] and organelles, for example) and [|cellular division].
 * Interacts extensively with cell membranes to keep the walls strong
 * **CYTOSKELETAL FILAMENTS OF EUKARYOTIC CELLS:**
 * 1) Microfilaments
 * 2) Intermediate Filaments
 * 3) Microtubules
 * II-B3.i. **Actin Fibers** /**MicroFilaments**
 * microfilaments are essential to [|transduction]. They are also important for [|cytokinesis]
 * act to maintain cellstructure
 * II-B3.i. **Intermediate** **Filaments**
 * more stable (strongly bound) than actin filaments, and heterogeneous constituents of the cytoskeleton
 * Like actin filaments, they function in the maintenance of cell-shape by bearing tension compression
 * II-B3.i. **Microtubules**
 * ** Functions : **
 * intracellular transport (associated with [|dyneins] and [|kinesins], they transport [|organelles] like [|mitochondria] or [|vesicles])
 * the [|axoneme] of [|cilia] and [|flagella]
 * the [|mitotic spindle].
 * synthesis of the cell wall in plants.


 * **II-B3. RIBOSOMES (proteins)**
 * Description: are complexes of [|RNA] and [|protein] that are found in all [|cells]. refer to the little dots on rough endoplasmic reticulum (5)
 * ** Function: The ribosome is part of the mechanism that ** Translate  ** the DNA sequence into the protein sequence. The ribosome is part of the mechanism that [|translates] the genetic code from nucleic acid into [|protein] chains. **
 * ** Structure ** - RNA & protein

II-B4. ENDOPLASMIC RETICULUMS (city highways)

 * **Structure ** : extentive membrane network of channels called cisternae which are held together by the <span style="font-family: Arial,Helvetica,sans-serif; font-size: 130%;"> <span style="font-family: Arial,Helvetica,sans-serif; font-size: 16.9px; line-height: 19px;">[|cytoskeleton]
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">**3 Types of Endoplasmic Reticulum:**
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">Rough Endoplasmic Reticulum
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">Smooth Endoplasmic Reticulum
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">Sarcoplasmic Reticulum
 * ===IIB2-i: ROUGH ENDOPLASMIC RETICULUM===
 * [[image:http://www.abbysenior.com/biology/cell_structure_files/image002.gif caption="Rough Endoplasmic Reticulum (red dots = ribosomes (protein molecules)"]]
 * <span style="font-family: Arial,Helvetica,sans-serif;"> **Function** : Primary concern with <span style="color: #882020; font-family: Arial,Helvetica,sans-serif;">protein synthesis <span style="font-family: Arial,Helvetica,sans-serif;"> <span style="color: #ff0000; font-family: Arial,Helvetica,sans-serif;"> <span style="font-family: Arial,Helvetica,sans-serif;">& <span style="color: #0029ff; font-family: Arial,Helvetica,sans-serif;">transport <span style="font-family: Arial,Helvetica,sans-serif;">. Most highly developed in protein exporting cells are the liver & pancreatic cells
 * **(1) Protein Synthesis :** a function by which a cell does **transcription & translation**
 * **//Transcription://**
 * **// step 1: Unzipping: a segment of DNA unzips, and enzyme (helicase) breaks the hydrogen bonds between the nitrogenous bases //**
 * step 2: RNA nucleotides bind with DNA nucleotides by Complementary Base Pairing on one of the two strands that are exposed after unzipping
 * step 3: Joining of adjacent Nucleotides
 * **//Translation//** is a process by which protein is produced by the ribosomes and also takes 3 steps
 * __step 1: Initiation__
 * __step 2: Elongation__
 * __step 3: Termination__

<span style="font-family: Arial,Arial,Helvetica;">
 * **IIB2-ii. SMOOTH ENDOPLASMIC RETICULUM (city highways)**
 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;">**<span style="font-family: Arial,Helvetica,sans-serif;">Structure ** <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: the structure is like the Rough Endoplasmic Recticulum except that channels dont have ribosomes attached.
 * [[image:http://www.abbysenior.com/biology/cell_s4.gif]]
 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;">**<span style="font-family: Arial,Helvetica,sans-serif;">Function ** <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12.6px; line-height: 21px;">: <span style="color: #800000; font-family: Arial,Arial,Helvetica; font-size: 12.6px; line-height: normal;">synthesizes and transports **lipids** and **steroids** <span style="font-family: Arial,Arial,Helvetica; font-size: 12.6px; line-height: normal;">. Some kinds of smooth E.R. accepts, modifies, and transports proteins from the rough E.R. and still other kinds break down energy rich glycogen and fats.

**II-B. GOLGI APPARATUS (post office) - refer to 8**

 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;">**<span style="font-family: Arial,Helvetica,sans-serif;">Structure ** <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: Arial,Arial,Helvetica; font-size: 12.6px; line-height: normal;">The golgi appear as flattened stacks of membranes. The proteins enter these membranes are modified, concentrated and packaged into small spherical membrane bound structures called **vesicles** <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12.6px; line-height: 21px;">.
 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;">**<span style="font-family: Arial,Helvetica,sans-serif;">Function ** <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12.6px; line-height: 21px;">: <span style="color: #800000; font-family: Arial,Arial,Helvetica; font-size: 12.6px; line-height: normal;"> **Modify** & **Transport** proteins that come from Smooth and Rough ERs <span style="font-family: Arial,Arial,Helvetica; font-size: 12.6px; line-height: normal;">.
 * It primarily modifies proteins delivered from the [|**rough endoplasmic reticulum**]
 * Also involved in the transport of [|lipids] around the cell, and the creation of [|**lysosomes**]. In this respect it can be thought of as similar to a post office; it packages and labels items which it then sends to different parts of the cell.
 * 1) <span style="font-family: Arial,Arial,Helvetica; line-height: normal;">Proteins are modified
 * 2) <span style="font-family: Arial,Arial,Helvetica; line-height: normal;">Enclosed in secretory or lysosomal vesicles
 * 3) <span style="font-family: Arial,Arial,Helvetica; line-height: normal;">then Transported OUT of the cell

II-B. VESCICLES (Ietters & packages from post office) - 4

 * **Function** - Contain products that have been packaged/modified by the golgi. (eg. proteins like enzymes, plasma proteins, peptide hormones etc.)
 * Most vesicles have specialized functions depending on what materials they contain.
 * Major Functions:
 * ** store **
 * [|transport]
 * [|digest] celluar products and waste.
 * The membrane enclosing the vesicle is similar to that of the [|plasma membrane], and vesicles can fuse with the plasma membrane to release their contents outside of the cell. Vesicles can also fuse with other [|organelles] within the cell.
 * **Structure**.
 * membrane-enclosed sac that stores or transports substances within a cell
 * It has the same structure as a **vacuole** only it is smaller in size. Structure W in the first diagram and structure Z in the second, show vesicles.

<span style="font-family: arial,helvetica,sans-serif;">

**II-B. LYSOMONES ( //recycling center// ) - 12**

 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;"> <span style="font-family: Arial,Helvetica,sans-serif;">** Description: A re small, spherical [|organelles] containing [|digestive enzymes] (acid [|hydrolases]) **
 * <span style="font-family: Arial,Helvetica,sans-serif;">** Function** **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: **
 * **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;"> Digest & Dispose <span style="font-family: arial,helvetica,sans-serif; font-size: 11.7px; font-weight: normal; line-height: 19px;"> of foreign particles, malfunctioning structures, and worn out orgganelles <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> . **
 * Lysosomes fuse with [|**vacuoles**] and dispense their enzymes into the [|vacuoles], digesting their contents

Some important enzymes found within lysosomes include:
 * <span style="font-family: Arial,Helvetica,sans-serif;">**Structure** **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: arial,helvetica,sans-serif; font-size: 11.7px; font-weight: normal; line-height: 19px;">Contains 40 different enzymes that are capable of breaking down virtually every large molecules <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> **
 * [|Lipase], which digests [|lipids]
 * [|Carbohydrase], which digest [|carbohydrates] (e.g., sugars)
 * [|Proteases], which digest [|proteins]
 * [|Nucleases], which digest [|nucleic acids]
 * [|phosphoric acid] monoesters.

II-B. MITOCHONDRIA ( power plant ) - 9

 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;">**<span style="font-family: Arial,Helvetica,sans-serif;">Function ** <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;">The chemical reactions which produce energy and the storage of that energy as ATP occur in this organelle. Glucose and Oxygen are used to produce ATP, carbon dioxide and water. Collectively these reactions are called aerobic respiration
 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;">**<span style="font-family: Arial,Helvetica,sans-serif;">Structure ** <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;"> Made up double membrane which creates two areas within the organelle
 * <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;">The area between the membranes houses the enzymes of the Kreb's cycle and is called **the matrix**.
 * <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;">the surface of the membranes, contains the enzymes of the electron transport system and is called **the cristae**.
 * Be able to recognize the cristae and matrix in the diagram of the mitochondria below



[[image:http://www.abbysenior.com/biology/cell_diagram.gif caption="Cell Structure (Be able to identify each section)"]]

 * <span style="font-family: arial,helvetica,sans-serif; font-size: 14px; line-height: 21px;"> <span style="font-family: Arial,Helvetica,sans-serif;">**Function** **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> acts to control the metabolic activities of the cell. Is the central control centre which monitors internal and external conditions and turns on or off different genetic programs **
 * <span style="font-family: Arial,Helvetica,sans-serif;">**General Structure** **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> is surrounded by a membrane which is similar in structure to the plasma or cell membrane. **
 * **<span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;">Nuclear pores or holes occur at intervals along the membrane. **
 * **<span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;">These holes provide a way for the nucleus to communicate with the cytoplasm. **
 * **<span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;">Substances pass in and out of the nucleus through these openings **
 * **Components of Nucleus:**
 * 1) **Nuclear Envelop**
 * 2) **Chromatin**
 * 3) **Nucleolus**
 * 4) **Nucleoplasm**

** B8-i: Nuclear Envelop **

 * **Function**: selectively permeable to control movement in or out
 * **Structure**:
 * contains 2 unit membranes with fluid-filled space
 * present nuclear pores
 * outer membrane may be continuous with endoplasmic reticulum

** B8-ii: Chromatin **
<span style="font-family: arial,helvetica,sans-serif;">
 * **Function**: Contains instructions that control cells metabolism and heredity
 * **Structure**: composed of long thin strands of DNA


 * <span style="font-family: Arial,Helvetica,sans-serif;">**Function** **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: **
 * **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;"><span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;">Rich in RNAs, this is where <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;">ribosomes <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> ( <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;">the <span style="color: #0000ff; font-family: arial,helvetica,sans-serif; font-size: 13px; line-height: 19px;">factories <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;">) are synthesizes **
 * Instructions in DNA are copied here

<span style="font-family: arial,helvetica,sans-serif;">
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> Structure<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;">
 * non-membraneous matrix of RNA (RiboNucleous Acid)
 * <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> consists of densely packed chromosomes, protein and precursor RNA strands from which the sub-units of ribosomes are formed.


 * <span style="font-family: Arial,Helvetica,sans-serif;">**Function** **<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: abc **
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> Structure<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14px; line-height: 21px;">: <span style="font-family: arial,helvetica,sans-serif; font-size: 13px; font-weight: normal; line-height: 19px;"> abc

**II-B**. Chromosomes ( Ixx )

 * **Function** - Carries the genetic code which determines characteristics of an organism.
 * **Structure:**
 * made up of genes which are in turn made up of DNA.
 * The chemical components and the order of the of the chemical components determine the specific characteristics.

II-B. Proteins ( workers )

 * **Function** - abc
 * **Structure** - abc

II-B**. Kinesin, Dynein ( Trucks )**

 * **Function** - abc
 * **Structure** - abc

II-B**. Genoides - DNA, RNA ( Library )**

 * **Function** - abc
 * **Structure** - abc

**I-B13. Chaperones ( Police Station )**

 * **Function** - abc
 * **Structure** - abc

**II-B**. Centrioles ( Ixx )

 * **Function** - abc
 * **Structure** - abc

II-B**. Cytosol ( Ixx )**

 * **Function** - abc
 * **Structure** - abc

II-B**. Flagellum ( Ixx )**

 * **Function** - abc
 * **Structure** - abc

>>

=III. CELL TRANSPORT=

=IV. HOMEOSTASIS=