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Cell Structure Cell Structure and Functionand Function

Organelle Structures of the CellOrganelle Structures of the Cell

Organelle: Organelle: Specialized structure of Specialized structure of the cell that carries out a specific the cell that carries out a specific function, “organ like”.function, “organ like”.The cell is often compared to a The cell is often compared to a factory.factory.These organelle structures work to These organelle structures work to produce a product.produce a product.

Cell Membrane (Both)Cell Membrane (Both) Composed of several molecules, the most Composed of several molecules, the most

important is important is Lipids, Lipids, which form a bilayer. which form a bilayer. The cell membrane separates the cell from The cell membrane separates the cell from

its surroundings.its surroundings. It regulates what enters & leaves the cell.It regulates what enters & leaves the cell. FunctionsFunctions: protection and support.: protection and support.

Cell Wall (Plant)Cell Wall (Plant)

Found in Plant, Algae, & some Bacteria.Found in Plant, Algae, & some Bacteria. Is found outside the cell membrane, it actually Is found outside the cell membrane, it actually

surrounds the cell membrane.surrounds the cell membrane. It is very porous, allows for water, oxygen, carbon It is very porous, allows for water, oxygen, carbon

dioxide and others to pass through it.dioxide and others to pass through it. The cell wall is both The cell wall is both elastic & rigid.elastic & rigid. Functions: Functions: Protection, Support, Regulation.Protection, Support, Regulation.

Nucleus (Both)Nucleus (Both)

Large dark round structure usually in the Large dark round structure usually in the center of the cell.center of the cell.

Is known as the information center of the Is known as the information center of the cell.cell.

Sometimes called the brain of the cell.Sometimes called the brain of the cell. Function: Function: To direct all activities of the cell To direct all activities of the cell

and store DNA.and store DNA.

Nucleolus (Both)Nucleolus (Both) Made up of RNA and other proteins.Made up of RNA and other proteins. Function: Function: To make ribosomes.To make ribosomes.

Nuclear Envelope (Both)Nuclear Envelope (Both) Two layer membrane that surrounds the nucleus, Two layer membrane that surrounds the nucleus, Function: Function:

Acts as border between the nucleus and the rest of the cell.Acts as border between the nucleus and the rest of the cell.

Chromosomes (Both)Chromosomes (Both) The DNA of the cell is stored on the chromosome inside The DNA of the cell is stored on the chromosome inside

the nucleus. Shaped like an the nucleus. Shaped like an X.X. The chromosome passes genetic information from The chromosome passes genetic information from

generation to generation.generation to generation.

Cytoplasm (Both)Cytoplasm (Both)

The space or area between the nucleus and The space or area between the nucleus and the cell membrane.the cell membrane.

Gel or jelly like.Gel or jelly like. Function: Function: Hold and/or support the Hold and/or support the

organelles.organelles.

Ribosomes (Both)Ribosomes (Both)

Small particles of RNA and protein found Small particles of RNA and protein found throughout the cytoplasm.throughout the cytoplasm.

Function: Function: To make proteins.To make proteins.

Endoplasmic Reticulum (Both)Endoplasmic Reticulum (Both) Is an internal membrane system.Is an internal membrane system. Function: Function: It is the site where the lipid It is the site where the lipid

components of the cell membrane are components of the cell membrane are assembled, along with proteins and other assembled, along with proteins and other materials.materials.

The part involved in making protein is The part involved in making protein is called the called the Rough Endoplasmic ReticulumRough Endoplasmic Reticulum, , it has ribosomes on its surface.it has ribosomes on its surface.

The The Smooth Endoplasmic Reticulum Smooth Endoplasmic Reticulum (doesn’t have ribosomes) stores enzymes (doesn’t have ribosomes) stores enzymes used to make lipid membranes.used to make lipid membranes.

Endoplasmic ReticulumEndoplasmic Reticulum

Golgi Apparatus (Both)Golgi Apparatus (Both)

Stack of closely apposed membranes.Stack of closely apposed membranes. Function: Function: It modifies, sorts, and packages It modifies, sorts, and packages

molecules for cell storage or secretion.molecules for cell storage or secretion.

Lysosomes (Both)Lysosomes (Both) Small organelles filled with enzymes that Small organelles filled with enzymes that

act as a act as a clean-up crewclean-up crew.. Function: Function: They digest or breakdown; They digest or breakdown;

lipids, carbohydrates, and proteins into lipids, carbohydrates, and proteins into smaller molecules so that they can be used smaller molecules so that they can be used by the cell.by the cell.

They also break down organelles that have They also break down organelles that have outlived their usefulness (remove junk that outlived their usefulness (remove junk that accumulates in the cell).accumulates in the cell).

Many serious diseases can be traced to Many serious diseases can be traced to lysosomes that fail to function properly.lysosomes that fail to function properly.

LysosomeLysosome

Vacuoles (Both)Vacuoles (Both)

Saclike structure.Saclike structure. Function: Function: stores (warehouse) materials stores (warehouse) materials

like; water, salt, proteins, and like; water, salt, proteins, and carbohydrates.carbohydrates.

Can be found in many different types of Can be found in many different types of cells (large central vacuole in plants, several cells (large central vacuole in plants, several smaller vacuoles in animals).smaller vacuoles in animals).

Play a major role in Homeostasis.Play a major role in Homeostasis.

VacuoleVacuole

Chloroplasts (Plant)Chloroplasts (Plant) It stores food and pigments.It stores food and pigments. Function: Function: stores chlorophyll(pigment), stores chlorophyll(pigment),

which captures energy from sunlight and which captures energy from sunlight and converts it into energy for the cell.converts it into energy for the cell.

May also be called a May also be called a Plastid.Plastid.

Mitochondria (Both)Mitochondria (Both) Function: Function: Converts chemical energy stored in Converts chemical energy stored in

food into energy that is more convenient for the food into energy that is more convenient for the cell to use. Known as the cell to use. Known as the powerhousepowerhouse..

Made of two membranes.Made of two membranes. The inner membrane has many folds to increase The inner membrane has many folds to increase

surface area to improve their function.surface area to improve their function.

Microfilaments (Both)Microfilaments (Both)

Thread like structure made of proteinThread like structure made of protein Function: Function: Helps in cell movement & Helps in cell movement &

support.support.

Microtubules (Both)Microtubules (Both) Hallow structure made up of a protein.Hallow structure made up of a protein. Function: Function: Plays a major role in maintaining Plays a major role in maintaining

cell shape and has a role in cell cell shape and has a role in cell reproduction.reproduction.

Centrioles(Animal)Centrioles(Animal)

Microtubule bundles Microtubule bundles Function: Function: Plays a role in cellular Plays a role in cellular

reproductionreproduction

Cytoskeleton (Both)Cytoskeleton (Both)

A network of protein filaments that A network of protein filaments that Function: Function: Helps the cell to maintain its Helps the cell to maintain its

shape.shape.– It also is involved in movement.It also is involved in movement.

Cellular OrganizationCellular Organization

Cell (Animal)--> Tissue (Cardiac)--> Organs (Heart)--Cell (Animal)--> Tissue (Cardiac)--> Organs (Heart)-->Organ System(Cardiovascular)--> Organisms (Humans)>Organ System(Cardiovascular)--> Organisms (Humans)