The Cell The structures within a cell function in providing protection and support, forming - PowerPoint Presentation

Slide1

The Cell

The structures within a cell function in providing protection and support, forming a barrier between the cell and its environment, building and repairing cell parts, transporting materials, storing and releasing energy, getting rid of waste materials, and increasing in number. These cell structures are called

organelles

.

A. The cell membrane provides

protection

and support for the

cell. Animal cells do not have a cell wall, therefore, the cell membrane must provide the support and protection for the cell.

The cell membrane controls the movement of materials into and out of the cells through pores. Everything from the movement of oxygen to waste particlesis controlled by the cell membrane. It keeps the cell in a state of homeostasis.

I. Cell Membrane: The

doorway

of the cell.

II. Nucleus: The

control

center of the cell.

A. The nucleus is a round structure in the cell that acts as the control center

(brain) of the cell. It regulates or controls all activities of the cell. Chromosomes are rod-like structures, located in the nucleus that direct all activities of the cell, including growth, reproduction, and the passing of traits.

III. Mitochondria:

Powerhouses

of the cell.

A. Mitochondria are rod-shaped structures that supply most of

the energy to the cell. Inside the mitochondria, simple food substances such as sugars are broken down into water and carbon dioxide gas. Large amounts of energy is released during the breakdown of sugars. The energy is collected and stored for

the cell to use.

IV

.

Ribosomes: Protein factories of the cell.

A. Ribosomes are grain-like bodies produced in the nucleus. Many of these bodies pass out of the nucleus and attach themselves to the inner lining of the edoplasmic reticulum. (Some ribosomes float freely in the cytoplasm.). B. Ribosomes are the protein making sites of the cell.

They

are found inside of

the

endoplasmic reticulum

so

that they may

be carried

to

anywhere in the cell

when

needed.

V. Endoplasmic Reticulum:

Transportation

system of the cell.

A.

The endoplasmic reticulum (ER) is a series of clear, tubular passageways. These passageways lead out from the nucleus to other areas of the cell or to the cell membrane. These passageways allow materials to be carried anywhere throughout the cell.B. The Rough ER is the endoplasmic reticulum with

ribosomes attached

to the outside and the Smooth ER is the

endoplasmic

reticulum

without

ribosomes.

VI

.

Lysosomes: Cleanup crews for the cell.

A. Small round structures involved with the digestive activities of the cell. 1. Lysosomes contain enzymes that break down large food molecules into smaller ones. These smaller food molecules are then passed on to the mitochondria where they are “burned”

to

provide energy for the cell.

The

lysosome

is covered in a

membrane

which keeps the

enzymes

in and from

digesting

the cell itself.

2. After

cell parts

outlive

their

usefulness,

Lysosomes

digest old

cell parts and

release

substances

to make

new

cell parts.

Lysosomes

(Continued)

B

.

Lysosomes are common in animal cells, but not often seen in plant cells.3. If the cell is injured or dead, the lysosomes’ enzymes can digest the whole cell such as when a tadpole becomes a frog and loses its tail.

VII

. Cytoplasm:

Suspension

system of the cell.

A. Cytoplasm is the region between structures in the cell that is a clear, thick, jelly-like substance.

VIII. Flagellum and Cilia:

Motion

makers for the cell.

A

. A flagellum is a tail-like structure that stick out from the cell. The flagellum moves back and forth enabling the cell to move.B. Cilia are hair-like structures that can be found on the outside of a cell. Cilia enable a cell to move and are

also used to pass water

and other materials over the cell’s surface.

IX

.

Vacuoles: Storage

tanks for the cell.

A. Vacuoles store mostly water, but also store other materials as well.B. Vacuoles are found in both plant and animal cells.

C

. Plants cells usually

have

one

large

centrally located

vacuole where

animals may have

several

small

ones.

.

X

.

Cell

Wall: Support and protection system for the cell.

A. Cell wall is only found in plant cells.B. Cell wall holds the plant cell up and enables the cell to keep its shape.

XI

.

Chloroplasts: Solar

power factories for the cell.

A. Chloroplasts are small green structures that are only found in the plant cell.B. Chloroplasts take the energy from the sun and turn it into food for the plant cell.

XII

.

Golgi Body: Mail and

package center of the cell.

A. Golgi bodies store, package and deliver the proteins and lipids made in the endoplasmic reticulum.

XIII

.

Centrioles: Guidance

counselors of the cell.

A. Centrioles line up the chromosomes inside the cell and then they pull the chromosomes apart during mitosis and guide them to the right location.

_______

___________

_______

____________________

_______

_______

___________

________

Cell Membrane

Nucleus

Mitochondria

Ribosomes

Endoplasmic

Reticulum

Lysosomes

Cytoplasm

Flagellum

Centrioles

Vacuole

Golgi Body

Animal Cell

Cell

Wall

Vacuole

Chloroplasts

Plant Cell