The Cell

Moretz, 2015

Biology

Outline

The Cell Theory

Cell Structure

Prokaryote vs. Eukaryote

Plant vs. Animal

Organelles, structure and function

Movement through the Cell

Cell membrane

Passive transport

Osmosis

Diffusion

Active transport

Endocytosis

Exocytosis

Types of Cells

HistoryBefore Microscopes, people believed

diseases were caused by curses and supernatural spirits.

Cells the basic unit of structure and

function in living things/organisms.

building blocks from which all living things are made.

Anton van Leeuwenhoek

Dutch 1600’s

Invented microscope

Used simple (one lens) microscope and natural light to view objects.

Robert Hooke

English Scientist (lived at the same time as Leeuwenhoek) 1665.

Discovered cells while looking at cork. (dead cells of oak bark)

Matthias Schleiden

German scientist 1830’s

Observed plants and concluded that plants are made up of cells.

Theodore Schwann

German Scientist

Observed animals and concluded that animals are made up of cells.

The Cell Theory

1) All living things are composed of cells.

2) Cells are the basic unit of structure and function in living things.

3) New cells are produced from existing cells.

Cells

Unicellular –organism made up of only 1 cell

Cells

Multicellular –organism made up of more than 1 cell

Cells

Unicellular or multicellular?

Cells

Cells

Types:

Prokaryote

Eukaryote

Animal cells

Plant cells

Cells

All cells contain:

Cytoplasm

Cell membrane

Ribosomes

Genetic information (DNA)

Comparison between

Prokaryotes and Eukaryotes

PROKARYOTES

No Nucleus

No membrane bound organelles

1-10 μm in size

Evolved 3.5 billion years ago

Only bacteria

EUKARYOTES

Nucleus

Many membrane bound organelles

2-100 μm in size

Evolved 1.5 billion years ago

All other cells

Prokaryote

Prokaryote Cells

Cells missing a nucleus and organelles.

DNA is in a single circle (plasmid).

All bacteria are prokaryotes.

All prokaryotes are unicellular.

Eukaryote

Have nucleus and membrane-bound organelles.

Eukaryote

Eukaryotes may be unicellular or multicellular

Eukaryote

Two types: Animal cells

Plant cells

Eukaryote

Animal Cells

Eukaryotic cell that does not contain a:

cell wall

large vacuole

Chloroplasts

Does NOTphotosynthesize.

Animal Cells

Plant Cells

Eukaryotic cell that contains:

large vacuole

Cell wall

chloroplasts

Photosynthesizes.

Plant Cells

Cell Parts

Cytoplasm

Found in all cells.

Semi-liquid medium that makes up the most of the cell.

Contains enzymes & nutrients that help reactions occur.

Cell Parts

Cell Membrane

Structure surrounding all cells.

Controls what molecules may enter and/or exit the cell.

Cell Parts

Ribosomes

Found in all cells.

Produces proteins.

Cell Parts

DNA

Found in all cells.

Contains the genetic information required for life.

1 circular strand in prokaryotes.

Many linear (double helix) strands in eukaryotes.

Cell Parts

Nucleus

Found in all eukaryotes.

Membrane bound structure that contains DNA.

Cell Parts

Endoplasmic Reticulum (ER)

Found in all eukaryotes.

Passageway in which proteins travel after being produced by ribosomes.

Produces new membranes.

Cell Parts

Golgi Apparatus

Found in all eukaryotes.

Packaging center for proteins and other cell products leaving the cell.

Cell Parts

Lysosome Found in

animal cells.

Digests food molecules.

Destroys worn-out cell parts.

May destroy the cell.

‘Suicide sac.’

Cell Parts

Mitochondria

Found in all eukaryotes.

Site of respiration.

Cell Parts Chloroplast

Found only in plant cells.

Site of photosynthesis.

Contains the pigment chlorophyll.

Appears green

Cell Parts

Plastids

Contain pigments

Produce chemicals for cells

In plant cells only

Cell Parts

Vacuole

Found in all eukaryotes.

Very large in plant cells.

Small organelles in animal cells.

Storage area for water and nutrients.

Cell Parts

Cell Wall

Found only in plant cells.

Adds structure and support to the cell.

Cell Parts

Centrioles

Moves chromosomes (DNA) around the cell during cell division.

In animal cells only

Movement of the Cell

Flagella

Whip-like tail used to move the cell.

Movement of the Cell

Cilia

Small, hair-like projections surrounding the cell. Used to move the cell.