Organelles: Structure & Function

Organelles: Structure & Function

Cell/Plasma Membrane

Structure: Phospholipid bilayer

Function: Controls what enters & exits the cell.

Nucleus

Structure: Contains DNA/chromosomes

Enclosed by a porous double membrane called the nuclear membrane.

Function: Controls everything in the cell

Nucleolus

Structure: Dense region inside the nucleus

Function: Takes RNA and makes ribosomes

Ribosomes

Structure: Tiny organelles made of proteins & RNA. Found on Rough ER

Function: Links together amino acids to make proteins (that means enzymes too!)

Rough Endoplasmic Reticulum (ER)

Structure: Thin folded membranes that are connected together.HAS ribosomes

Function: Transport, "intracellular highway“. Site of protein synthesis; makes more ER

VesicleMembrane-bound containers that carry substances throughout the cell

Golgi Apparatus/Body/Comple

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Structure: Closely layered stacks of membrane enclosed discs

Function: Checks, modifies & packages proteins

Lysosome

Structure: Contains enzymes; membrane bound

Function: Breaks down food, waste & damaged cell parts all within the cell

Peroxisome

Structure: Contains enzymes; membrane bound

Function: Protects cell from toxins, especially H2O2.

Vacuole

Structure: fluid filled sacs; small in animal cells; large in plant cells

Function: stores materials for cell

Plastids

Structure: 3 different types

Function: Storage sacs in plant cells only!

Plastids1.Leucoplast – stores starch in roots & stems

2.Chromoplast – stores the orange/yellow pigment

3.Chloroplast- stores the green pigment/ site of photosynthesis

Chloroplast

Structure: 3 membranes; bean shaped; contains chlorophyll (green pigment)

Function: Uses sunlight to create food, photosynthesis (only found in green plants & algae)

Mitochondria

Structure: Bean shaped; 2 membranes; has own DNA & ribosomes

Function: Supplies energy to the cell; site of cellular respiration; ‘powerhouse’ of cell

Chloroplast & MitochondriaBoth have: more than 1 membrane

‘Powerhouse’ of their cells

Contain their own DNA

Reproduce independently of the cell

Were they once free-living prokaryotic cells?!

Cytoplasm/Cytosol

Structure: Jelly – like substance between the area of the nucleus & cell membrane

Function: Hold organelles in place & site for chemical reactions

Cytoskeleton

Structure: A network of protein filaments (microtubules, microfilaments)

Function: Supports & shapes the cell

Smooth Endoplasmic Reticulum (ER)

Structure: Thin folded membranes that are connected together.

No ribosomes

Function: Transport, "intracellular highway“. Also makes lipids; breaks down toxins such as drugs/alcohol

Centrosome/Centrioles

Structure: Small region of cytoplasm, made up of microtubules; pair of centrioles

Function: Helps the cell divide

Flagellum (flagella = plural)

Tail used for movement

Cilium (cilia = plural)Tiny hair-like projections on cell exterior used

For movement and gathering food