chapter 4 section 3: looking inside cells. looking inside cells organelles = tiny structures found...

Chapter 4

Section 3: Looking Inside Cells

Looking Inside Cells

Organelles = tiny structures found inside of the cells.

Think organs of the cell.

The Organelles of the Cell

Cell WallONLY in plant cellsProvides protection and support for the cell.

Think Prison Walls.

The Organelles of the Cell

Cell MembraneControls what enters and exits the cell.

Think prison guard of the cell.

The Organelles of the Nucleus

Nucleus The brain of the

cell, the control center.

Controls all the activities of the cell.

The Organelles of the Nucleus

Nuclear Membrane Protects the

nucleus

Think about the yolk of an egg and how there is a thin barrier that holds it together.

The Organelles of the Nucleus

Chromosomes Rod shaped Contain thin strands

called Chromatin. Chromatin has the

genetic material = DNA

The Organelles of the Nucleus

Nucleolus Produces

ribosomes.

The Organelles of the Cytoplasm

Cytoplasm is the region between the cell membrane and the nucleus.

Cytoplasm is a thick, always moving liquid.

The Organelles of the Cytoplasm

Mitochondria Found in the

cytoplasm Rod shaped

organelles Produce energy The more active the

cell, the more mitochondria they have.

The Organelles of the Cytoplasm

Endoplasmic Reticulum Found in the

cytoplasm Is like a giant maze Carries the proteins

and other materials from one part of the cell to another.

The Organelles of the Cytoplasm

Ribosome Small grain like

bodies attached to the Endoplasmic Reticulum.

Produce proteins Proteins are sent to

the Golgi Bodies

The Organelles of the Cytoplasm

Golgi Bodies Flattened collections of

sacs and tubes. Receive the proteins

and other newly formed material from the endoplasmic reticulum.

Mailroom of the cell. Release materials

outside the cell.

The Organelles of the Cytoplasm

Chloroplasts Capture energy

from the sun.“think solar panels”

Use energy to create food.“photosynthesis”

ONLY in plant cells.

The Organelles of the Cytoplasm

Vacuoles Large water filled sacs Storage area of the

cell. Food Materials Needed Waste products

Without water in the vacuoles, plants begin to wilt.

The Organelles of the Cytoplasm

Lysosomes Small round structures Break down food

particles . Break down old cell

parts so that they can be reused again.

Have powerful chemicals that are contained by a membrane.

Bacterial Cells

Has a cell wall and membrane.Does NOT have a nucleus.Contain ribosomes, but none of the other

organelles found in plant or animal cells.

Prokaryotes vs. Eukaryotes

Organisms that do not contain a nucleus.

PROKARYOTES

Organisms that contain a nucleus.

EUKARYOTES

Structure and Function in Cells

Different cells perform different functions. Examples:

Plants have root cells that are specialized to absorb water from the soil.

Nerve cells are specialized to carry messages that enable the animal to respond to external and internal stimuli. They have long, threadlike projections that act something like telephone wires. These “wires” carry messages throughout your body.

Red blood cells carry oxygen throughout the body. Their thin, flexible structure helps them squeeze through tiny blood vessels.

Levels of Organization

Multi cellular organisms have four levels of organization.

1. Cells

2. Tissues

3. Organs

4. Organ Systems

Smallest

Biggest

Cell

Tissues

A group of similar cells that perform a specific function in an organism.

specialized for functions such as absorbing materials, transporting materials, and support.

Example:Bone tissue produce a hard, strong material

that supports the body.

Tissues

Organs

A structure in the body that is composed of different kinds of tissue.

Example:Bones, which support the body, are hard

and sturdy because of the tissues of which they are composed.

Organs

Organ System

A group of organs that work together to perform a major function in the body.

Example: The skeletal system functions to support the body and

give it shape. The skeleton protects delicate internal organs such as

the brain and lungs. The strength and hardness of bones enable the

skeleton to perform the functions of support and protection.

The structure and arrangement of bones give the body its shape.

Organ System

The 5th Level

Every organism interacts with other organisms and the environment in which it lives.

Scientists add another level of organization: the population.

Population = All the members of one species in a particular area.