Organization of Organization of Living ThingsLiving Things

What Are the Main What Are the Main Characteristics of Characteristics of

organisms?organisms?1.Made of CELLS2.Require ENERGY (food)3.REPRODUCE4.RESPOND to stimuli5.GROW and DEVELOP6.Genetic material (DNA)

First to View CellsFirst to View Cells• In 1665,

Robert Hooke used a microscope to examine a thin slice of cork (dead plant cell walls)

First to View CellsFirst to View Cells

Hooke called them “CELLS” because they looked like the small rooms that monks lived in called Cells

Anton van Leeuwenhoek

• In 1673, Leeuwenhoek (a Dutch microscope maker), was first to view organism (living things)

• Leeuwenhoek used a simple, handheld microscope to view pond water & scrapings from his teeth

Number of CellsNumber of CellsAlthough ALL living things are

made of cells, organisms may be:

• Unicellular – composed of one cell

• Multicellular - composed of many cells that may organize into tissues, etc.

Cell Size and TypesCell Size and Types

• Cells can only be observed under microscope

• Three Basic types of cells include:

Animal Cell Plant CellBacterial

Cell

Which Cell Type is Which Cell Type is Larger?Larger?

Plant cell Animal cell bacteria

Prokaryotes – The first Prokaryotes – The first CellsCells

•Cells that lack a nucleus •Includes all bacteria•Simplest type of cell

ProkaryotesProkaryotes

• DNA without a nucleus

• Surrounded by cell membrane & cell wall

• Contain ribosomes in their cytoplasm to make proteins

Eukaryotes

• Cells that HAVE a nucleus

• Includes protists, fungi, plants, and animals

• More complex type of cells

Two Main Types of Eukaryotic Cells

Plant Cell

Animal Cell

Cell or Plasma MembraneCell or Plasma Membrane

Cellmembrane

Proteins

Proteinchannel Lipid bilayer

Carbohydratechains

•Two layers of phospholipids and proteins

•Surrounds the cell•Controls what enters or leaves the cell

Cell WallCell Wall•Supports and protects cell

•Found outside of the cell membrane

Found in plants, fungi, and bacteria

Cell wallCell WallCell Wall

•Jelly-like substance

•Where chemical reactions take place

•Contains organelles to carry out specific jobs

•Found in ALL cells

Cytoplasm of a Cytoplasm of a Cell Cell

cytoplasm

•Controls the activities of the cell

•Contains the DNA in chromosomes

•Usually the largest organelle

•Connected to the rough ER

The Control Center - The Control Center - NucleusNucleus

Nucleolus

•Inside the Inside the nucleusnucleus

•Makes Makes ribosomesribosomes

Endoplasmic Reticulum - EREndoplasmic Reticulum - ERTwo kinds of ER ---ROUGH & SMOOTH

Rough ER:Where proteins are made

Endoplasmic Reticulum - EREndoplasmic Reticulum - ERTwo kinds of ER ---ROUGH & SMOOTH

Smooth ER: Makes lipids, regulates calcium, and detoxifies cells

MitochondrionMitochondrion(plural = mitochondria)(plural = mitochondria)

• “Powerhouse” of the cell

•Generate cellular energy (ATP)

•More active cells like muscle cells have MORE mitochondria

RibosomesRibosomes

Can be attached to Rough ER

OR

Be free (unattached

) in the cytoplasm

Join amino acids to make

proteins

Golgi BodiesGolgi Bodies

•Receive Receive proteinsproteins made made by ERby ER

•Transport Transport vesiclesvesicles carry carry packaged packaged proteins proteins throughout the throughout the cellcell

Transport

vesicle

LysosomesLysosomes

•Contain Contain digestive digestive enzymesenzymes

•Break down Break down food, bacteria,food, bacteria, and and worn out worn out cell partscell parts

VacuolesVacuoles•Fluid filled

sacks for storage

•Small or absent in animal cells

•Plant cells have a large Central Vacuole

ChloroplastsChloroplasts•Found only in

producers •Photosynthesis -

energy from sunlight to make food (glucose)

Organization Organization Levels of LifeLevels of Life

Atoms to OrganismsAtoms to Organisms

LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

Nonliving Levels:

1.ATOM (element)

2.MOLECULE (compounds like

carbohydrates & proteins)

3.ORGANELLES (nucleus, ER, Golgi

…)

CELLS – life starts here

TISSUES – Similar cells working together

Living LevelsLiving Levels

ORGANSORGAN SYSTEMS ORGANISM

Different tissuesworking together

Different organsworking together

More Living LevelsMore Living Levels

TissueTissue

•A group of similar cells to perform a particular function–Animals : skin tissue, muscular tissue

–Plants : vascular tissue (xylem and phloem)

OrganOrgan

• Different tissues group together to carry out specialized functions– Heart : consists of muscles,

nervous tissue, and blood vessels

– Leaf : consists of epidermis and vascular tissue

Stoma

Air Space

Spongy Mesophyll Cell

Chloroplast

The Structures of a Leaf (Plant Organ)

Palisade Mesophyll Cell

The Structures of a Heart (Animal Organ)

SystemSystem• Several organs and tissues work together

to carry out a particular set of functions in a coordinated way– Human : digestive, respiratory, excretory,

circulatory and reproductive systems– Plant : root and shoot systems

LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

Living Levels:

1.CELL (makes up ALL organisms)

2.TISSUE (cells working together)

3.ORGAN (heart, brain, stomach …)

4.ORGAN SYSTEMS (respiratory, circulatory,

digestive, etc …)

5.ORGANISM