LC BIOLOGY- Cell Structure

Cell Wall

• is made of cellulose

• provides support

Protoplasm

all the living parts of a cell

Cytoplasm

the living material in a cell outside the nucleus

Ultrastructure

the detail of a structure as seen using an electron microscope

Chromatin

name given to chromosomes when they are elongated and not dividing

Prokaryotic Cells

do not have a nucleus or membrane-enclosed organelles

Eukaryotic Cells

have a nucleus and cell organelles, all of which are enclosed by membranes

Cell Membrane

• surrounds the cell

• controls the entry and exit of molecules to the cell

Nucleus

• controls the cell

• contains chromosomes, which have DNA (elongated, non-dividing chromosomes are called chromatin)

DNA

found in chromosomes or chromatin in the nucleus

Nucleolus

makes ribosomes

Vacuoles

• strengthens the cell

• storage

Mitochondria

• provide energy (through respiration)

• are numerous in active cells

• may have many infoldings (cristae) which imply a large energy output

Chloroplasts

are green and carry out photosynthesis

Ribosomes

make protein

Prokaryotic Cells

• do not have a nucleus or membrane-enclosed organelles

• are smaller and more primitive than eukaryotic cells

• are found as bacteria (monera)

Eukaryotic Cells

• have a membrane-enclosed nucleus and cell organelles

• are larger and more advanced than prokaryotic cells

• are found as plant and animal cells, fungi, and amoeba

Observing Cells

• prepare and stain cells on a slide

• examine under low power, then high power

• stain plant cells using iodine solution

• stain animal cells using methylene blue