Structures & Functions of Living Organisms

Living OrganismsWhat do you think is the largest living

organism?What do you think is the smallest living

organism?

Make a list in your notebook of 5 of the largest and 5 of the smallest living things that you can think of.

What really is the smallest organism?

Single Celled OrganismsWhat characteristics do single celled

(unicellular) organisms have in common?

Single Celled OrganismsHow do unicellular organisms differ from one

another?

Single Celled OrganismsWhat characteristics do unicellular

organisms such as the ones you have just seen share with multicellular organisms such as birds, dogs, or humans?

Single Celled OrganismsHow do these unicellular organisms get

nourishment, water, and oxygen and get rid of waste?

Single Celled OrganismsHow do unicellular organisms move?

Single Celled OrganismsHow do unicellular organisms reproduce?

Single Celled OrganismsA CELL is the basic unit of life.

These single celled organisms are classified as PROTISTS.

Protists are unicellular EUKARYOTIC organisms.

Eukaryotic means cells that have membrane bound organelles. The organism’s DNA is found inside a nucleus.

Types of Single Celled OrganismsThere are 3 major classes of Protists:

Animal-like protistsPlant-like protistsFungus-like protists

Animal-like ProtistsThe PARAMECIUM is animal-like

It has short hair-like structures, called CILIA, that beat rapidly to move the paramecium along.

Animal-like ProtistsThe AMOEBA is animal-like

It moves and eats by extending it’s false foot to surround it’s food.

Plant-like ProtistsThe EUGLENA is plant-like.

It has CHLOROPLASTS which allow it to make it’s own food.

The process of making it’s own food is called PHOTOSYNTHESIS

A euglena moves by whipping it’s FLAGELLUM around.

This is a picture of a Euglena

Plant-like ProtistsThe VOLVOX is plant-like.

It is a type of green algae that can be found in groups called colonies.

Usually found in fresh water.

Lots of Organelles!Organelles are like little organs for the cell,

carrying out specific jobs for the cell to function properly.

Cell membrane: semi-permeable membrane that holds the cell together and allows gases to pass through it.

Cytoplasm: the liquid inside the cellContractile vacuole: moves water in and out

of the cellFood vacuole: where food is digestedNucleus: where DNA is storedPseudopod: a “false foot” used for movement

Lots of Organelles!Chloroplast: where photosynthesis occursGullet & Mouth Pore: mouth-like area that

takes in foodEyespot: used to detect light for plant-like

protistsFlagellum: whip-like tail used for locomotionCilia: hair-like structures along the outside of

the cell used for locomotionOral groove: pushes food into a food vacuole

for digestionAnal pore: passes waste out of the cell

How can we see these things?These organisms are MICROSCOPIC.

We need to use a microscope in order to see them.

Do you remember how to use a microscope??

TIME TO PRACTICE!Now it’s your turn to practice your

microscope skills!Make sure to follow ALL directions on the lab

sheet.