Organization of Organisms

​-tiny box like structures (cells)

-phographed through a microscope (photomicrograph)

-60X Magnification

-2mm long in picture, 0.03 mm long in life

​Plant Cell

If you cut ALONG THE LENGTH of the structure

If you cut ACROSS the structure

thin slices

-Magnified 700X

-treated with dyes (STAIN) for structures to show up clearly

​

​Features present in most animal cells

Cytoplasm

• ​looks like a thick liquid with particles in it

• chemical reactions take place

• liquid part is about 90% water with molecules of salt and sugars dissolved in it

• fats (lipids), proteins (enzymes) are suspended

• others float freely

Cell membrane

• thin boundary enclosing the cytoplasm

• controls substances which are allowed to enter and leave the cell

• oxygen, food and water are allowed to enter, waste products are allowed to leave

Nucleus

• rounded structure enclosed in a membrane

• control the type and quantity of enzymes produced by the cell

• determines what the cell will be (blood cell, liver cell, muscle cell, nerve cell)

• controls cell division

Nucleus

• cell without nucleus cannot reproduce

• inside the cell are thread-like structures called CHROMOSOMES

Chromosomes can be seen easily when cells are dividing

​Features in most Plant Cell

​Cell Wall

• ​contains cellulose

• it is non-living

• allows water and dissolved substances to pass through

• not selective like cell membrane

​Vacuole

• ​large, liquid-filled space

• contins cell sap (a watery solution of sugar, salts and sometimes pigments

​Plastids

• ​if they contain green substance chlorophyll, it is called CHLOROPLAST

• colorless plastids usually contain starch used as a food storage

​Palisade

Spongy

Vascular tissues:

Xylem-water conducting

Phloem-food conducting

​Palisade mesophyll cell