THE CELL

Contributors to Knowledge of CellRobert Hooke (1665)- Discovered the cellAnton van Leeuwenhoek (mid-1600s)-

viewed living organisms under microscopeMatthias Schleiden (1838)- plants are

made of cellsTheodor Schwann (1839)- animals are

made of cellsRudolf Virchow (1855)- new cells are

produced only from division of old cells

The Cell TheoryThe discoveries of Hooke, Schleiden,

Schwann, and Virchow are summarized in the cell theory, which states that:

All living things are composed of cells.

Cells are the basic units of structure and function in living things.

New cells are produced from existing cells.

Types of Cells

Types of CellsProkaryotic Eukaryotic

No nucleus present Nucleus present

No membrane bound organelles

Membrane bound organelles

Smaller in size Larger in size

Primitive/older cells Younger/newer cells

Contains DNA, ribosomes, cytoplasm, & cell membrane

Contains DNA, ribosomes, cytoplasm, & cell membrane

Ex: Bacteria Ex: Plant and animal cells

Cell PartsDescriptions

FunctionsLocationCell type

CytoplasmJelly -like substanceMade mostly of waterHolds all organellesBetween the cell membrane and nuclear membrane

Both plant and animal cell

Cell(plasma) membraneOuter portion of the cellBoundaries of inside organelles

Controls movement inside and outside of the cell

Both plant and animal cells

Animal Cell

Nucleus•Round dark organelle in cytoplasm

•Control center for cell

•Contains DNA/chromatin and nucleolus

•Both plant and animal cells

Nuclear Membrane (envelope)

•Membrane that surrounds nucleus

•Controls movement of materials in and out of nucleus

•Both plant and animal cells

Nucleolus

Located in nucleus, dark spots

Made of chromatin

Makes ribosomes

Both plant and animal cells

Microtubules(cytoskeleton)Microtubules (cytoskeleton)Thin protein strands, but thicker

than microfilamentsProvide support for cellAide in movementBoth plant and animalFound in cytoplasm

Microfilaments(cytoskeleton)Microtubules (cytoskeleton)Thin protein strands, but thinner

than microtubulesProvide support for cellAide in movementBoth plant and animalFound in cytoplasm

CentriolesCylinder shaped, each cell has a pairHelp cell divide

ONLY in animal cells

Found in cytoplasm

VacuoleSac shaped vesicleUsed for storage of food, water, and wastes

Much larger in plant cellsBoth plant and animal cellsLocated in cytoplasm

ChloroplastLocated in the cytoplasm

Green from chlorophyll

Used in photosynthesis to make food

Only in plants

RibosomesSmall circles or dots located in

cytoplasm or on the Endoplasmic Reticulum

Made by the nucleolus

Make protein

Both plant and animal cells

Cell WallLayer outside cell membrane in plant cells

Give cell support/shape

Made of cellulose

Only in plant cells

Golgi Apparatus(complex, bodies)Located in cytoplasm

Looks like fruit rollups

Packages materials in vessicles and ships them to the needed locations

Adapts proteins made by ribosomes

Both plant and animal cells

MitochondriaDouble membrane organellePowerhouse of the cell, releases the cell’s energy from stored food

Contains its own DNA If cell requires more energy (muscle) it will have more mitochondria

Both plant and animal cells

Endoplasmic ReticulumNetwork of tubes connecting cell membrane to other

organellesSER makes lipids

RER makes proteins

Transports materials throughout cell

Can be rough (with ribosomes) or smooth (without ribosomes)

Both plant and animal cells

Chromosomes/ChromatinThread like genetic material

Located in nucleus

Contains all the information for the cells’ activities

Both plant and animal cells

ChromatidsTwo strands make up a chromosome

Located in the nucleus except during cell division where they are pulled apart by the centrioles

Used in the duplication of the cell

Both plant and animal cells

CiliaHair like structures attached to the cell membrane

Responsible for movement

In animal cells

FlagellumHair like structure attached to the cell membrane

Responsible for movement

In animal cells

LysosomesSac like structure that contains

chemical that help in digestion and breaking down materials

Located in the cytoplasm

Only in animal cells